阅读说明：本技术 电化学元件、电化学元件层叠体、电化学模块、电化学装置和能源系统 (Electrochemical element, electrochemical element laminate, electrochemical module, electrochemical device, and energy system ) 是由 越后满秋 大西久男 神家规寿 曾木忠幸 南和彻 于 2020-03-27 设计创作，主要内容包括：目的在于,提供能够提高发电效率的技术。电化学元件具有板状支撑体10,所述板状支撑体10在内侧具有内部流路A1,板状支撑体10具有：气体流通允许部1A,其能够跨前述内部流路A1与板状支撑体10的外侧而透过气体；和电化学反应部3,其是至少膜状的电极层31、膜状的电解质层32和膜状的对电极层33在板状支撑体10的外表面上、在覆盖气体流通允许部1A的全部或一部分的状态下按顺序在规定的层叠方向上层叠形成；内部流路A1中流通第一气体,且设置形成第一气体的湍流状态的湍流形成体90,所述第一气体是还原性成分气体和氧化性成分气体之中的一者。(An object is to provide a technique capable of improving power generation efficiency. The electrochemical element has a plate-shaped support 10, the plate-shaped support 10 having an internal flow path A1 therein, the plate-shaped support 10 having: a gas flow-permitting part 1A through which gas can pass between the internal flow path a1 and the outside of the plate-like support 10; and an electrochemical reaction part 3 formed by laminating at least a film-like electrode layer 31, a film-like electrolyte layer 32, and a film-like counter electrode layer 33 in order in a predetermined laminating direction on the outer surface of the plate-like support 10 in a state of covering all or a part of the gas flow-allowing part 1A; a turbulent flow forming body 90 that forms a turbulent flow state of the first gas, which is one of the reducing component gas and the oxidizing component gas, is provided to flow the first gas through the internal flow path a 1.)

1. An electrochemical element having a plate-shaped support body having an internal flow path inside,

the plate-like support has:

a gas flow-allowing unit through which gas can pass between the internal flow path and the outside of the plate-like support; and

an electrochemical reaction part formed by laminating at least a film-like electrode layer, a film-like electrolyte layer, and a film-like counter electrode layer in order in a predetermined laminating direction on the outer surface of the plate-like support in a state of covering all or a part of the gas flow-allowing part;

a turbulent flow forming body is provided for forming a turbulent flow state of a first gas, which is one of a reducing component gas and an oxidizing component gas, while the first gas is circulated through the internal flow path.

2. The electrochemical element according to claim 1, wherein the internal flow channel has a plurality of sub-flow channels extending in a first direction in a direction along the plate-shaped surface of the plate-shaped support and extending in a second direction intersecting the first direction in the direction along the plate-shaped surface while being spaced from each other,

the turbulent flow forming body has a turbulent flow forming portion which is arranged in at least 1 of the plurality of sub flow paths and forms a turbulent flow state of the first gas.

3. The electrochemical element according to claim 1 or 2, wherein the turbulence forming body is a mesh body provided in the internal flow passage along the plate-shaped surface of the plate-shaped support.

4. The electrochemical element according to claim 1 or 2, wherein the turbulence forming body is a granular body provided in the internal flow path.

5. The electrochemical element according to any one of claims 1 to 4, wherein the plate-like support is formed using a conductive material.

6. The electrochemical element according to any one of claims 1 to 5, wherein the plate-like support is formed using a metal material.

7. The electrochemical element according to any one of claims 1 to 6, wherein the turbulence forming body is formed using a conductive material.

8. The electrochemical element according to any one of claims 1 to 7, wherein the turbulence forming body is formed using a metal material.

9. An electrochemical module having:

an electrochemical element laminate in which a plurality of the electrochemical elements according to any one of claims 1 to 8 are laminated in a predetermined lamination direction; and

and a holder including a first holder that presses a first plane of the electrochemical element stacked body in the stacking direction, and a second holder that presses a second plane opposite to the first plane.

10. The electrochemical module according to claim 9, wherein in the electrochemical element stack, a plurality of the electrochemical elements are stacked in the stacking direction via an annular seal portion through which the first gas flows.

11. The electrochemical module according to claim 10, wherein the first gas is introduced into the internal flow path of the plate-shaped support via the annular seal portion,

and a flow passage through which a second gas, which is the other of the reducing component gas and the oxidizing component gas, flows is formed between the electrochemical elements adjacent to each other in the stacking direction.

12. The electrochemical module according to claim 10 or 11, wherein a first electrochemical element and a second electrochemical element among the plurality of electrochemical elements are stacked adjacent to each other,

introducing the first gas into the inner flow path of the plate-like support via the annular seal portion,

the plate-shaped support body constituting the first electrochemical element and the plate-shaped support body constituting the second electrochemical element are opposed to each other, and an outer surface of the plate-shaped support body constituting the first electrochemical element on which an electrochemical reaction part is arranged is electrically connected to another outer surface of the plate-shaped support body constituting the second electrochemical element on the side on which the electrochemical reaction part is arranged, and a flow part through which a second gas, which is the other of a reducing component gas and an oxidizing component gas, flows is formed between the two outer surfaces along the two outer surfaces.

13. The electrochemical module according to claim 12, wherein the plate-like support of each electrochemical element has a first penetration portion forming a supply passage through which the first gas flows,

the first through-hole of each electrochemical element communicates with an annular hole of an annular seal portion existing between adjacent electrochemical elements.

14. The electrochemical module according to claim 13, wherein the flow passage has therein a first annular seal section as the annular seal section that separates the first penetration section and the flow passage formed on the outer surfaces,

the supply passage through which the first gas flows is formed between the first through-hole and the internal passage by the first annular seal portion.

15. The electrochemical module according to claim 13 or 14, wherein the plate-shaped support has a second penetration portion that forms a discharge passage through which the first gas flowing through the internal flow passage flows outside a surface penetration direction of the plate-shaped support,

the flow passage has a second annular seal portion as the annular seal portion that separates the second penetration portion formed on each of the two outer surfaces from the flow passage,

the second penetrating portion and the second annular seal portion form the discharge passage through which the first gas flowing through the internal flow passage flows.

16. An electrochemical device having at least:

the electrochemical element according to any one of claims 1 to 8 or the electrochemical module according to any one of claims 9 to 15; and

a fuel converter for flowing a gas containing a reducing component into the electrochemical element or the electrochemical module, or a fuel converter for converting a gas containing a reducing component generated in the electrochemical element or the electrochemical module.

17. An electrochemical device comprising at least the electrochemical element according to any one of claims 1 to 8 or the electrochemical module according to any one of claims 9 to 15, and a power converter for extracting electric power from or supplying electric power to the electrochemical element or the electrochemical module.

18. An energy system comprising the electrochemical device according to claim 16 or 17 and a waste heat utilization unit for reusing heat discharged from the electrochemical device or the fuel converter.

Technical Field

The invention relates to an electrochemical element, an electrochemical element laminate, an electrochemical module, an electrochemical device, and an energy system.

Background

Patent document 1 discloses a fuel cell stack in which a fuel cell and a separator made of a porous material are alternately laminated. The fuel cell unit includes an electrolyte membrane, an oxidant electrode, and a fuel electrode. An oxidant electrode is formed on one surface of the electrolyte membrane, and a fuel electrode is formed on the other surface. An oxidizing gas flow path is formed in the separator facing the oxidizing electrode along a planar direction, and the oxidizing gas flows through the oxidizing gas flow path. Similarly, a fuel gas flow path is formed in the separator facing the fuel electrode in the planar direction, and the fuel gas flows through the fuel gas flow path. The stack thus formed generates electricity by an electrochemical reaction between a fuel gas containing hydrogen and an oxidant gas containing oxygen.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2017-188224.

Disclosure of Invention

Problems to be solved by the invention

In the fuel cell described in patent document 1, an electrolyte membrane, an oxidant electrode, and a fuel electrode are stacked in this order, and an oxidant gas and a fuel gas flow in a laminar state along the plane direction. In the laminar flow state, the gas flows while suppressing disturbance of the flow.

In recent years, in order to improve the power generation efficiency in the fuel cell, a new structure of the stack has been studied. Further, it is also expected to investigate the flow state of gases such as an oxidant gas and a fuel gas in a fuel cell comprising the laminate.

The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of improving power generation efficiency.

Means for solving the problems

[ constitution ]

The electrochemical device according to the present invention is characterized in that,

comprises a plate-shaped support body having an internal flow path on the inner side,

the plate-like support has:

a gas flow-allowing unit through which gas can pass between the internal flow path and the outside of the plate-like support; and

an electrochemical reaction part formed by laminating at least a film-like electrode layer, a film-like electrolyte layer, and a film-like counter electrode layer in order in a predetermined laminating direction on the outer surface of the plate-like support in a state of covering all or a part of the gas flow-allowing part;

a turbulent flow forming body is provided for forming a turbulent flow state of a first gas, which is one of a reducing component gas and an oxidizing component gas, while the first gas is circulated through the internal flow path.

With the above-described characteristic configuration, the first gas flows through the internal flow path of the plate-shaped support body. The turbulence forming body that forms a turbulent state of the first gas is provided in the internal flow passage, and therefore the first gas easily forms a turbulent state in the internal flow passage. In the turbulent flow state, the fluid flows through the flow path in a state where at least a part of the fluid swirls. Therefore, the fluid in a turbulent state flows mainly in the flow path direction thereof in the flow path, and also flows in a direction different from the flow path direction. Therefore, the first gas travels along the plane of the plate-shaped support body forming the internal flow passage, and easily permeates from the internal flow passage across the outside through the gas flow-allowing portion formed on the plate-shaped support body. This improves the efficiency of supplying the first gas to the electrochemical reaction portion formed on the outer surface of the plate-like support, promotes the electrochemical reaction in the electrochemical reaction portion, and improves the power generation efficiency.

In particular, with the miniaturization of the electrochemical element, the internal flow channel is flattened, and the width and height thereof are narrowed, and the first gas may be in a laminar state traveling along the plane of the plate-shaped support. In addition, when the power generation output of the electrochemical element having the electrochemical reaction unit is reduced, the supply amount of the first gas to the internal flow path is adjusted to be small. As described above, when the amount of the first gas flowing through the internal flow path is small, the first gas may be in a laminar state traveling along the plane of the plate-shaped support. However, by the presence of the turbulence-forming body, the first gas is easily formed into a turbulent state. Therefore, the efficiency of supplying the first gas from the internal flow path to the electrochemical reaction unit via the gas flow-allowing unit is improved.

[ constitution ]

The electrochemical device according to the present invention is further characterized in that,

the internal flow path has a plurality of sub flow paths extending in a first direction in a direction along the plate-shaped surface of the plate-shaped support and extending in a direction along the plate-shaped surface so as to be separated from each other in a second direction intersecting the first direction,

the turbulent flow forming body has a turbulent flow forming portion which is arranged in at least 1 of the plurality of sub flow paths and forms a turbulent flow state of the first gas.

With the above-described characteristic configuration, the plurality of sub-channels extending in the first direction in the direction along the plate-shaped surface of the plate-shaped support are formed in the internal channel of the plate-shaped support. At least 1 of the plurality of sub-channels is provided with a turbulence forming portion which forms a turbulence forming body. In the secondary flow path provided with the turbulent flow forming portion, the first gas flows in a laminar flow state along the plane of the plate-like support in the secondary flow path along the first direction, and is also easily formed in a turbulent flow state. Therefore, the first gas in a turbulent state not only travels along the plane of the plate-shaped support forming the internal flow path, but also easily permeates from the internal flow path across the outside through the gas flow-allowing portion formed on the plate-shaped support. This improves the efficiency of supplying the first gas to the electrochemical reaction section, promotes the electrochemical reaction in the electrochemical reaction section, and improves the power generation efficiency.

[ constitution ]

The electrochemical device according to the present invention is further characterized in that,

the turbulent flow forming body is a mesh body provided in the internal flow path along the plate-like surface of the plate-like support.

According to the above feature, the turbulent flow forming body may be formed of a mesh body along the plate-like surface of the plate-like support. The first gas can be set in a turbulent state by flowing through the mesh body.

Examples of the turbulence forming body of the mesh body include members such as a metal mesh, expanded metal (expanded metal), expanded metal (foamed metal), metal felt, pressed metal, and 3D fabric.

[ constitution ]

In the electrochemical device according to the present invention, the turbulent flow forming body is a granular body provided in the internal flow passage.

According to the above feature, the turbulent flow forming body may be formed of granular particles provided in the internal flow passage. The first gas collides with the particulate matter, whereby the first gas can be brought into a turbulent flow state.

[ constitution ]

The electrochemical device according to the present invention is further characterized in that the plate-like support is formed using a conductive material.

According to the above-described characteristic configuration, since the plate-shaped support is formed using the conductive material, the current flowing between the plate-shaped support and the electrochemical reaction portion becomes smooth, and the internal resistance of the electrochemical element can be reduced. As a result, a high-performance electrochemical device can be obtained.

[ constitution ]

In the electrochemical device according to the present invention, the plate-shaped support is formed using a metal material.

According to the above-described characteristic configuration, the plate-like support is formed using a metal material, and therefore, has toughness and excellent workability in addition to conductivity. Thus, a compact and lightweight, low-cost electrochemical element is obtained.

[ constitution ]

In the electrochemical device according to the present invention, the turbulent flow forming body is formed using a conductive material.

According to the above-described characteristic configuration, since the turbulent flow forming body is formed using the conductive material, the current flowing to the electrochemical reaction portion becomes smooth, and the internal resistance of the electrochemical element can be reduced. As a result, a high-performance electrochemical device can be obtained.

[ constitution ]

In the electrochemical device according to the present invention, the turbulent flow forming body is formed using a metal material.

According to the above characteristic configuration, the turbulent flow forming body is formed using a metal material, and therefore, the turbulent flow forming body has toughness and excellent workability in addition to having electrical conductivity. Thus, a compact and lightweight, low-cost electrochemical element is obtained.

[ constitution ]

The electrochemical module according to the present invention is characterized by comprising:

an electrochemical element laminate in which a plurality of the above-described electrochemical elements are laminated in a predetermined lamination direction; and

and a holder including a first holder that presses a first plane of the electrochemical element stacked body in the stacking direction, and a second holder that presses a second plane opposite to the first plane.

With the above-described characteristic configuration, the electrochemical module can be configured by sandwiching the electrochemical element stacked body between the first sandwiching member and the second sandwiching member.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

in the electrochemical element laminate, a plurality of the electrochemical elements are laminated in the lamination direction via an annular seal portion through which the first gas flows.

According to the above configuration, since the plurality of electrochemical elements are stacked in the predetermined stacking direction via the annular seal portion, leakage of the first gas between the plurality of electrochemical elements can be suppressed.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

introducing the first gas into the inner flow path of the plate-like support via the annular seal portion,

and a flow passage through which a second gas, which is the other of the reducing component gas and the oxidizing component gas, flows is formed between the electrochemical elements adjacent to each other in the stacking direction.

With the above-described characteristic configuration, each electrochemical element has an internal flow path through which a first gas flows inside the plate-shaped support, and a flow portion through which a second gas flows is formed between adjacent electrochemical elements. Therefore, each electrochemical element can perform an electrochemical reaction by the first gas supplied from the internal flow channel and the second gas supplied from the flow portion.

More specifically, when the electrochemical element functions as a fuel cell (electrochemical power generation unit) that "converts chemical energy of fuel or the like into electric energy", the first gas is one of a reducing component gas such as hydrogen and an oxidizing component gas such as air that are consumed by an electrochemical reaction, and the second gas is the other.

When the electrochemical element functions as an electrolysis cell that "converts electric energy into chemical energy such as fuel", the first gas is one of a reducing component gas such as hydrogen and an oxidizing component gas such as oxygen generated by an electrochemical reaction, and the second gas is the other.

Further, the plate-like support body has: a gas flow-permitting section that is permeable to gas and that spans between an inner flow path that is an inner side of the plate-shaped support and an outer side; and an electrochemical reaction section having an electrode layer, an electrolyte layer, and a counter electrode layer in a state of covering all or a part of the gas flow-allowing section. Therefore, when the electrochemical element functions as a fuel cell (electrochemical power generation unit), the first gas and the second gas reach the electrochemical reaction section through the passage from the outside of the substrate and the passage from the internal flow path through the gas flow-allowing section of the plate-shaped support, and react with each other in the electrode layer and the counter electrode layer, thereby causing an electrochemical reaction such as generation of electricity.

When the electrochemical element functions as an electrolysis cell, electricity is supplied to the electrochemical reaction unit, and water or the like is electrolyzed to generate the first gas and the second gas, which can be discharged from the passages on the outer side of the plate-shaped support and the passages in the internal flow passages from the gas-flow-allowing portion of the plate-shaped support.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

in the plurality of electrochemical elements, a first electrochemical element and a second electrochemical element are stacked adjacent to each other,

the first gas is introduced into the internal flow path of the plate-like support through the annular seal portion,

the plate-shaped support body constituting the first electrochemical element and the plate-shaped support body constituting the second electrochemical element are opposed to each other, and an outer surface of the plate-shaped support body constituting the first electrochemical element on which the electrochemical reaction section is arranged is electrically connected to another outer surface of the plate-shaped support body constituting the second electrochemical element on the side on which the electrochemical reaction section is arranged, and a flow section through which a second gas, which is the other of a reducing component gas and an oxidizing component gas, flows is formed between the two outer surfaces along the two outer surfaces.

With the above-described characteristic configuration, the electrochemical element has the internal flow path inside the plate-shaped support, and the first gas flows through the internal flow path. On the other hand, the second gas flows through a flow section partitioned from the internal flow path. Therefore, the first gas and the second gas can be distributed and circulated.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

the plate-like support body of each electrochemical element has a first through-hole portion for forming a supply passage through which the first gas flows,

the first through-hole of each electrochemical element communicates with an annular hole of an annular seal portion existing between adjacent electrochemical elements.

According to the above-described characteristic configuration, the first gas is supplied to the stacked body in which the plurality of electrochemical elements are stacked via the first penetration portion and the annular seal portion of each electrochemical element.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

the flow part has a first annular seal part as the annular seal part for separating the first penetration part and the flow part formed on the two outer surfaces,

the first through-hole and the first annular seal portion form the supply passage through which the first gas flows between the internal flow passages.

By providing the first annular seal portion, the first through portions of the electrochemical elements stacked on each other in the stacked body can be isolated from and connected to the flow portion. Therefore, by the extremely simple configuration in which the first through portions of the adjacent electrochemical elements are tightly connected to each other, the electrochemical elements can be connected to each other in a form that can be operated appropriately using the first gas and the second gas, and an electrochemical module with high reliability and easy fabrication and easy handling can be formed.

The annular seal portion may have any shape as long as it is configured to prevent gas leakage by allowing the through portions to communicate with each other. That is, the annular sealing portion may have an endless configuration having an opening portion therein communicating with the penetration portion, and may be configured to seal the adjacent electrochemical elements. The annular seal portion is, for example, annular. The ring shape may be any shape such as a circle, an ellipse, a square, or a polygon.

[ constitution ]

The electrochemical module according to the present invention is further characterized in that,

the plate-like support has a second penetration portion that forms a discharge passage through which the first gas flowing through the internal flow passage flows outside the surface penetration direction of the plate-like support,

the flow passage has a second annular seal portion as the annular seal portion that separates the second penetration portion formed on each of the two outer surfaces from the flow passage,

the second penetrating portion and the second annular seal portion form the discharge passage through which the first gas flowing through the internal flow passage flows.

That is, for example, in the case where the electrochemical element functions as a fuel cell (electrochemical power generation unit), the first gas that has entered the internal flow path from the first penetration portion passes through the internal flow path, flows through the electrochemical reaction portion via the gas flow-allowing portion, and the remaining portion flows through the second penetration portion that forms the discharge path. Since the discharge passage forms the second penetration portion in a state of being separated from the second gas, the first gas can be recovered from the discharge passage in a state of being separated from the second gas. Since the discharge passage is constituted by the sealing portion, similarly to the supply passage in the first penetration portion, it is possible to connect the adjacent electrochemical elements in a state of separating the flow portions by a very simple constitution in which the second penetration portions of the electrochemical elements are tightly connected to each other, and the electrochemical elements can be connected in a form in which the electrochemical elements are appropriately operated by using the first gas and the second gas, thereby forming an electrochemical module which is easy to manufacture and has reliability, and a structure which is easy to handle when manufacturing the electrochemical module.

[ constitution ]

The electrochemical device according to the present invention is characterized in that,

at least comprising: the above electrochemical element or the above electrochemical module; and a fuel converter for flowing a gas containing a reducing component into the electrochemical element or the electrochemical module, or a fuel converter for converting a gas containing a reducing component generated in the electrochemical element or the electrochemical module.

The fuel cell system according to the above feature configuration includes an electrochemical element or an electrochemical module, and a fuel converter for flowing a gas containing a reducing component into the electrochemical element or the electrochemical module. Therefore, when the electrochemical module is operated as a fuel cell, if a configuration is adopted in which hydrogen gas is generated from natural gas or the like supplied using existing raw fuel supply infrastructure such as city gas by a fuel converter such as a reformer and the like and is circulated through the fuel cell, an electrochemical device having an electrochemical module with excellent durability, reliability and performance can be realized. Further, it is easy to construct a system for recycling the unused fuel gas discharged from the electrochemical module, and therefore a highly efficient electrochemical device can be realized.

Further, according to the above-described characteristic configuration, the fuel cell system includes an electrochemical element or an electrochemical module, and a fuel converter that converts a gas containing a reducing component generated in the electrochemical element or the electrochemical module. Therefore, when the electrochemical module operates as an electrolysis cell, for example, a hydrogen gas generated by an electrolysis reaction of water can be converted into methane or the like by a reaction with carbon monoxide or carbon dioxide in a fuel converter, and if such a configuration is adopted, an electrochemical device having an electrochemical module with excellent durability, reliability, and performance can be realized.

[ constitution ]

The electrochemical device according to the present invention is characterized in that,

at least comprising: the electrochemical device or the electrochemical module, and a power converter that extracts electric power from the electrochemical device or the electrochemical module or supplies electric power to the electrochemical device or the electrochemical module.

With the above-described characteristic configuration, the power converter extracts electric power generated by the electrochemical element or the electrochemical module or supplies electric power to the electrochemical element or the electrochemical module. Thus, the electrochemical element or the electrochemical module operates as a fuel cell or as an electrolysis cell as described above. Therefore, according to the above configuration, it is possible to provide an electrochemical device and the like capable of improving the efficiency of converting chemical energy such as fuel into electric energy or converting electric energy into chemical energy such as fuel.

For example, when an inverter is used as a power converter, it is preferable to use an inverter because the electric output obtained from the electrochemical device or the electrochemical module having excellent durability, reliability, and performance can be boosted by the inverter or the direct current can be converted into the alternating current, and therefore the electric output obtained from the electrochemical device or the electrochemical module can be easily used.

[ constitution ]

The energy system according to the present invention is characterized in that,

the fuel cell system includes the electrochemical device and a waste heat utilization unit for reusing heat discharged from the electrochemical device or the fuel converter.

According to the above feature configuration, since the electrochemical device and the exhaust heat utilization unit that reuses heat discharged from the electrochemical device or the fuel converter are provided, an energy system having excellent durability, reliability, and performance and excellent energy efficiency can be realized. In combination with a power generation system that generates power by using combustion heat of unused fuel gas discharged from an electrochemical device or a fuel converter, a hybrid system having excellent energy efficiency can be realized.

Drawings

Fig. 1 is a cross-sectional view of an electrochemical module.

Fig. 2 is a top view of an electrochemical module.

Figure 3 is a side view of an electrochemical module.

Fig. 4 is a schematic view of an electrochemical module.

Fig. 5 is a schematic view of an electrochemical element.

Fig. 6 is a sectional view VI-VI in fig. 5.

Fig. 7 is a view from VII to VII in fig. 5.

Fig. 8 is a sectional view VIII-VIII in fig. 5.

Fig. 9 is a cross-sectional view IX-IX in fig. 5.

Fig. 10 is an X-X sectional view in fig. 5.

FIG. 11 is a cross-sectional view XI-XI in FIG. 5.

Fig. 12 is a sectional view XII-XII in fig. 5.

FIG. 13 is a cross-sectional view XIII-XIII in FIG. 5.

Fig. 14 is an enlarged view of a key portion of the electrochemical reaction portion.

Fig. 15 is a schematic diagram of an energy system.

Fig. 16 is a sectional view IX-IX in fig. 5 identical to fig. 9 in an electrochemical element with another turbulence-forming body.

Fig. 17 is the same cross-sectional X-X view of fig. 5 as fig. 10 in an electrochemical cell having another turbulently-formed body.

Fig. 18 is a cross-sectional view XIII-XIII in fig. 5, the same as fig. 13, in an electrochemical element with another turbulently-formed body.

Fig. 19 is an explanatory view of an electrochemical module according to another embodiment.

Fig. 20 is a schematic view of another energy system.

Fig. 21 is a schematic view of another electrochemical element.

Fig. 22 is a sectional view XXII-XXII in fig. 21.

Fig. 23 is a view from XXIII to XXIII in fig. 21.

Fig. 24 is a sectional view XXIV-XXIV in fig. 21.

Fig. 25 is a sectional view XXV-XXV in fig. 21.

Fig. 26 is a sectional view XXVI-XXVI in fig. 21.

Fig. 27 is a sectional view XXVII-XXVII in fig. 21.

Fig. 28 is a sectional view XXVIII-XXVIII in fig. 21.

Fig. 29 is a sectional view XXIX-XXIX in fig. 21.

FIG. 30 is a cross-sectional view of XXX-XXX in FIG. 21.

FIG. 31 is a cross-sectional view of XXXI-XXXI in FIG. 21.

FIG. 32 is a cross-sectional view of XXXII-XXXII in FIG. 21.

FIG. 33 is a cross-sectional view of XXXIII-XXXIII in FIG. 21.

FIG. 34 is a cross-sectional view of XXXIV-XXXIV in FIG. 21.

FIG. 35 is a cross-sectional view of XXXV-XXXV in FIG. 21.

FIG. 36 is a cross-sectional view of XXXVI-XXXVI in FIG. 21.

Fig. 37 is an enlarged view of a key portion of the electrochemical reaction portion.

Fig. 38 is an explanatory view of the supply structure and the discharge structure.

Detailed Description

[ embodiment ]

The electrochemical module M and the method of assembling the electrochemical module M according to the embodiment of the present invention will be described below. In the case of representing the positional relationship of the layers, for example, the electrolyte layer side viewed from the electrode layer is referred to as "upper" or "upper side", and the first plate-like body side is referred to as "lower" or "lower side". In addition, the present invention provides the same effect even if the electrochemical module M is disposed in a vertical or horizontal direction, and thus "up" and "down" may be replaced with "left" and "right", respectively.

(1) Integral construction of electrochemical Module M

The overall structure of the electrochemical module M will be described below. As shown in fig. 1, the electrochemical module M includes an electrochemical element laminate (laminate) S, and a substantially rectangular parallelepiped container (casing, first holder, second holder) 200 in which the electrochemical element laminate S is housed. The electrochemical element a (fig. 4) is an element that generates electricity, and is formed in a plate shape extending from the front edge of the sheet toward the inside of the sheet in the cross-sectional view of fig. 1. The electrochemical element laminate S is configured by laminating a plurality of flat plate-like electrochemical elements a in the vertical laminating direction in the cross-sectional view of fig. 1. In the present embodiment, an SOFC (Solid Oxide Fuel Cell) is taken as an example of the electrochemical element a.

The electrochemical module M includes a first gas supply unit 61 that supplies a first gas from outside the container 200 to the electrochemical element stack S, and a first gas discharge unit 62 that discharges the first gas reacted in the electrochemical element stack S.

As shown in fig. 1 to 3, the container 200 is provided with a second gas supply unit 71 for supplying a second gas from the outside of the container 200 to the electrochemical element stack S. The second gas reacted in the electrochemical element stacked body S is discharged to the outside from the second gas discharge portion 72 provided in the container 200.

Here, the first gas is a reducing component gas such as a fuel gas, for example, and the second gas is an oxidizing component gas such as air.

In the cross-sectional view of fig. 1, the electrochemical module M has plate members 240 with openings on both side surfaces of the electrochemical element stack S. The plate member 240 with openings corresponds to both side surfaces of the electrochemical element stack S, is a plate-shaped member extending in the stacking direction of the electrochemical elements a, and is preferably made of an insulating material such as mica or alumina in order to prevent electrical short-circuiting (short-circuiting) in the electrochemical module M. The plate member with openings 240 has a plurality of openings 240a formed therein, which penetrate along the planar direction of the electrochemical element stack S.

Therefore, the electrochemical cell stack S receives the supply of the fuel gas from the first gas supply unit 61, and receives the supply of the air from the second gas supply unit 71 through the opening 240a of the plate member 240 with the opening, and electrochemically reacts the fuel gas and the oxygen in the air to generate electricity. The fuel gas after the electrochemical reaction is discharged to the outside from the first gas discharge portion 62. The air after the electrochemical reaction is introduced into the second gas discharge portion 72 through the opening 240a of the plate member 240 with an opening, and is discharged from the second gas discharge portion 72 to the outside.

Here, the plate members 240 with openings are provided adjacent to both side surfaces of the electrochemical element laminate S, but these are not essential, and either one may be provided or both may be omitted.

The electrochemical module M includes an upper insulator 210T and an upper plate (first holder) 230T in this order from the electrochemical element stack S side to the outside in the upper portion of the electrochemical element stack S. Similarly, the electrochemical module M includes a lower insulator 210B and a lower plate (second holder) 230B in this order from the electrochemical element stack S side to the outside in the lower portion of the electrochemical element stack S.

The electrochemical element laminate S will be described in detail later.

(2) Insulator, plate and container

Hereinafter, the insulators (upper and lower insulators 210T and 210B)210, the plates (upper and lower plates 230T and 230B)230, and the container 200 will be further described.

The upper insulator 210T is a plate-like member and is disposed so as to cover the upper plane (second plane) of the electrochemical element stack S. The upper insulator 210T is made of, for example, hard mica, and electrically insulates the electrochemical element stack S from the outside.

The upper plate 230T is a plate-shaped member, is disposed above the upper insulator 210T, and is formed of a ceramic material having high bending strength at high temperature, for example, 99 alumina.

The upper plate 230T receives a predetermined fastening pressure from the container 200 together with the lower plate 230B, and sandwiches the electrochemical element stackA body S, and a pair of upper and lower insulators 210T and 210B. Here, the fastening pressure means, for example, every 1mm²And the pressure per unit area.

The lower insulator 210B is disposed so as to cover the lower plane (second plane) of the electrochemical element stack S. The lower plate 230B is disposed below the lower insulator 210B. The lower insulator 210B and the lower plate 230B are identical to the upper insulator 210T and the upper plate 230T, respectively.

The container 200 containing the electrochemical element stacked body S is a substantially rectangular parallelepiped container as shown in fig. 1 to 3. The container 200 includes a box-shaped upper cover (first holder) 201 having a lower opening, and a lower cover (second holder) 203 having an upper opening. The upper cover 201 has a coupling portion 202 on an end surface facing the lower cover 203. A coupling portion 205 is provided on an end surface of the lower cover 203 facing the upper cover 201. The coupling portion 202 and the coupling portion 205 are coupled to the upper cover 201 and the lower cover 203 by, for example, welding, and a rectangular parallelepiped space is formed inside.

In the present embodiment, as shown in fig. 1, the lower cover 203 has a depth in the vertical direction (stacking direction of the electrochemical elements a) that is deeper than the upper cover 201. However, the upper cover 201 and the lower cover 203 are not limited to this as long as they can integrally form a space inside. For example, the upper cover 201 may be deeper than the lower cover 203.

As shown in fig. 1 to 3, a second gas supply portion 71 and a second gas discharge portion 72 are formed in the center portion of the container 200 in the vertical direction and on a pair of side walls of the lower cover 203 that face each other.

Here, the second gas supply portion 71 and the second gas discharge portion 72 are formed in the lower cover 203. However, the formation positions of the second gas supply portion 71 and the second gas discharge portion 72 are not limited thereto, and may be formed at any position of the container 200. The second gas supply part 71 and the second gas discharge part 72 may be formed on, for example, the upper cover 201.

As shown in fig. 1 and 2, the upper cover 201 has an opening 201c that is one turn smaller than the outer edge of the upper cover 201. In the cross-sectional view of fig. 1, the end portion facing the inside of the electrochemical element stacked body S adjacent to the opening 201c is branched into a1 st end portion 201a and a2 nd end portion 201 b. The first end 201a extends in a planar direction by a predetermined length toward the inside of the container 200, and the second end 201b branches from the first end 201a and extends below the container 200 by a predetermined length. The first end 201a and the second end 201b form substantially 90 ° in a cross-sectional view, and form an L-shaped corner. The corner of the L-shape is formed along the outer edge inside the outer edge of the top view of the upper cover 201 shown in fig. 2. Thus, as shown in fig. 1 and 2, an opening 201c, which is smaller than the outer edge of the upper cover 201 by one turn, is formed on the upper surface of the upper cover 201 through the terminal end of the first end portion 201 a.

The lower cover 203 has a first end 203a and a second end 203b that form an L-shaped corner of approximately 90 ° in the cross-sectional view shown in fig. 1, similarly to the upper cover 201. As shown in fig. 1, an opening 203c that is smaller than the outer edge of the lower cover 203 is formed at the terminal end of the first end 203 a.

As shown in fig. 1, the upper ends of a pair of plate members 240 with openings, an upper insulator 210T, and an upper plate 230T are fitted into the corners of the L-shape formed by the first end 201a and the second end 201b of the upper cover 201. Specifically, the upper plate 230T along the planar direction of the electrochemical element stacked body S is supported such that the upper surface of the outer peripheral end thereof is in contact with the lower surface (a part of the inner surface of the corner of the L-shape) of the first end 201 a. The plate member 240 with an opening along the side surface of the electrochemical element stacked body S is supported by the outer surface of the upper end thereof being in contact with the inner surface (a part of the inner surface of the corner of the L) of the 2 nd end 201 b. The upper insulator 210T is supported by an L-shaped corner portion formed by the first end 201a and the second end 203b via the upper plate 230T and the plate member 240 with an opening.

Similarly, the lower ends of the pair of plate members 240 with openings, the lower insulator 210B, and the lower plate 230B are fitted into the corners of the pair of L-shapes facing the planar direction of the lower cover 203.

The electrochemical element stack S is supported on its upper surface by the upper cover 201 via the upper plate 230T and the upper insulator 210T. The electrochemical element laminate S is supported on its lower surface by the lower cover 203 via the lower plate 230B and the lower insulator 210B.

With such a configuration, the upper cover 201 and the lower cover 203 are joined by, for example, welding the joining section 202 and the joining section 205 while sandwiching the electrochemical element stacked body S, the upper and lower insulators 210T and 210B, the upper and lower plates 230T and 230B, and the like from the upper and lower portions. At this time of connection, the upper cover 201 and the lower cover 203 are connected to each other by applying a predetermined fastening pressure to the electrochemical element stack S and the like. That is, in a state where the upper cover 201 and the lower cover 203 are coupled, a predetermined fastening pressure is applied to the electrochemical element stacked body S, the upper and lower insulators 210T and 210B, and the upper and lower plates 230T and 230B.

As shown in fig. 3, an opening 203e is formed in a side surface of the lower cover 203. Therefore, a part of the side surface of the electrochemical element laminate S is exposed through the opening 203 e. Further, by forming the openings 201c, 203c and the opening 203e in the container 200, the container 200 can be reduced in weight, and the material required for the container 200 can be reduced. In the case where the side surface of the electrochemical element laminate S is in contact with the upper cover 201 or the lower cover 203 or both of them, and thus there is a possibility of electrical short circuit (short circuit), a side surface insulator 245 made of a material such as mica is provided between the electrochemical element laminate S and the side surface of the upper cover 201 or the lower cover 203.

The lower cover 203 and the upper cover 201 of the container 200 are joined to each other, thereby applying a tightening pressure to the electrochemical element stacked body S. Examples of the material of the container 200 include ferritic stainless steel, martensitic stainless steel, and a composite of these with ceramics. These materials have a small thermal expansion rate as compared with austenitic stainless steel, and for ferritic stainless steel, SUS430 is about 11 × 10^-6/℃。

Further, as for the thermal expansion coefficient of the martensitic stainless steel, SUS403 and SUS420J1 are about 10.4 × 10^-6SUS410 and SUS440C were about 10.1X 10/° C^-6V. C. Further, it is preferable to select a material having excellent corrosion resistance for the container 200.

The material of the electrochemical element stack S is preferably the same as that of the container 200. In other words, the materials of the electrochemical element stack S and the container 200 preferably have the same thermal expansion coefficient as that of the container 200. In this case, the substrate of the electrochemical element stack S and the container 200 are thermally expanded to the same extent when the electrochemical element a generates electricity at a high temperature, for example. Therefore, for example, the thermal expansion difference between the substrate of the electrochemical element a and the container 200 can be reduced, and thus breakage of the electrochemical element S and leakage of the first gas and the second gas from the container 200 can be suppressed.

(3) Method for assembling electrochemical module M

Next, a method of assembling the electrochemical module M will be described.

A plurality of electrochemical elements a are stacked to prepare an electrochemical element stack S. The constitution and the manufacturing method of the electrochemical element laminate S are as described below.

Further, a container 200 for housing the electrochemical element stack S is prepared. The container 200 is not limited to this, but may be manufactured by, for example, a lost wax casting method. In the case of using the lost wax casting method, a cavity mold corresponding to the outer shape of the container 200 is manufactured by a thermoplastic material containing, for example, beeswax, rosin, or the like. The mold is covered with a refractory material containing silica sand, lime powder, or the like. Thereafter, the mold covered with the refractory is heated, and the mold made of a thermoplastic material is eluted. Thereby, a cavity corresponding to the mold for molding the shape of the container 200 is formed inside the refractory. The material of the vessel 200 is injected into the cavity and, after curing, the refractory material is removed. Thus, the container 200 having the upper cap 201 and the lower cap 203 is manufactured by the lost wax casting method. Note that the upper cover 201 and the lower cover 203 may be manufactured separately.

Next, for example, a pair of plate members 240 with openings are disposed on both side surfaces of the electrochemical element stack S, and the insulator 210 and the plate 230 are sequentially disposed on the upper plane and the lower plane of the electrochemical element stack S, and then, the stack is accommodated in the lower cover 203. The lower cover 203 is covered with the upper cover 201, and the lower cover 203 and the upper cover 201 are welded or the like to be joined to each other by adjusting the position of the electrochemical element stack S so as to apply a predetermined fastening pressure. Thereby, the electrochemical module M is assembled.

As described above, when the container 200 is manufactured by the lost wax casting method, cost reduction can be achieved by thinning, precision reduction, and mass production.

Further, by forming the box-shaped container 200, in the present embodiment, a space for a line of air to be supplied from the second gas supply portion 71 to the electrochemical element stacked body S can be provided.

(4) Specific constitution of electrochemical Module M

Next, a specific configuration of the electrochemical module M will be described with reference to fig. 1 and 4. Fig. 1 shows the electrochemical element laminate S of fig. 1 in detail.

As shown in fig. 1 and 4, the electrochemical module M includes: a container 200 (upper lid 201 and lower lid 203) in which the electrochemical element stack S is housed; a first gas supply unit 61 that supplies a first gas from the outside of the container 200 to the internal flow path a1 through the supply path 4; a first gas discharge part 62 that discharges the first gas after the reaction; a second gas supply unit 71 for supplying a second gas from the outside of the container 200 to the flow unit a 2; a second gas discharge unit 72 for discharging the reacted second gas; and an output unit 8 for obtaining an output associated with the electrochemical reaction in the electrochemical reaction unit 3;

the container 200 includes a distribution chamber 9 for distributing and supplying the second gas supplied from the second gas supply unit 71 to the flow unit a 2.

The distribution chamber 9 is a space located on the side of the electrochemical element stack S where the second gas is supplied to the electrochemical element stack S,

the flow portion a2 is open on the space side and communicates with the space.

The electrochemical element laminate S is housed in the container 200 in a state of being sandwiched between the pair of current collectors 81 and 82, the output portion 8 is provided extending from the current collectors 81 and 82, and is freely connected to power supply to the outside of the container 200, and at least one of the current collectors 81 and 82 is electrically insulated from the container 200, and is housed in such a manner that the first gas is airtight with respect to the container 200.

As a result, the electrochemical module M is supplied with the fuel gas from the first gas supply portion 61 and simultaneously with the air from the second gas supply portion 71, so that the fuel gas enters as indicated by the broken line arrows and the air enters as indicated by the solid line arrows in fig. 1 and 4.

The fuel gas (also referred to as a first gas) supplied from the first gas supply portion 61 is guided from the first penetration portion 41 of the uppermost electrochemical element a of the electrochemical element stack S to the supply passage 4, and flows through the supply passages 4 partitioned by the first annular seal portion 42 to the internal flow passages a1 of all the electrochemical elements a. The air (also referred to as a second gas) supplied from the second gas supply portion 71 once flows into the distribution chamber 9, and then flows into the flow portion a2 formed between the electrochemical elements a.

Then, if the second plate-like member 2 (a part of the plate-like support 10) is used as a reference, the portion of the second plate-like member 2 that has a wave-plate shape and protrudes from the first plate-like member 1 (a part of the plate-like support 10) can be electrically connected by contacting the electrochemical reaction parts 3 of the adjacent electrochemical elements a while forming the internal flow path a1 between the first plate-like member 1 and the second plate-like member 2. On the other hand, the portion of the corrugated plate-shaped second plate-shaped body 2 in contact with the first plate-shaped body 1 is electrically connected to the first plate-shaped body 1, and the flow portion a2 is formed between the electrochemical reaction portion 3 of the electrochemical element a adjacent to the second plate-shaped body 2.

The turbulent flow forming body 90 is provided in the internal flow path a1 to form a turbulent flow state of the fuel gas flowing through the internal flow path a 1. The internal flow path a1 includes a distribution portion a12 and a sub-flow path a11 (see fig. 4, 9, and the like), and the turbulence generating body 90 is preferably provided in the sub-flow path a 11.

The turbulence forming body 90 is constituted by the turbulence forming portions 91 provided in at least 1 of the sub-flow passages a11 among the plurality of sub-flow passages a 11. That is, the turbulence forming portions 91 provided in the respective sub flow paths a11 are collectively referred to as turbulence forming members 90. As described above, the turbulence-forming portions 91 may be provided in at least 1 of the sub-flow passages a11, and preferably, the turbulence-forming portions 91 are provided in all of the sub-flow passages a 11. Hereinafter, each of the sub-passages a11 is provided with a turbulent flow forming portion 91 that forms the fuel gas flowing through each of the sub-passages a11 into a turbulent flow state.

In a part of fig. 14, there are electrochemical element a in which the cross section including the internal flow path a1 appears and electrochemical element a in which the cross section including the flow portion a2 appears are shown in parallel for convenience, but the fuel gas supplied from the first gas supply portion 61 reaches the distribution portion a12 (see fig. 5, 7, and 9), flows while widening in the width direction of one end portion side through the distribution portion a12, and reaches each sub-flow path a11 (see fig. 5, 7, and 9) in the internal flow path a 1. In this case, the first gas can be equally distributed in the plurality of sub-channels a11 from the distribution portion a12, and electrochemical outputs can be equally generated in the electrochemical elements.

In this way, the fuel gas introduced into each of the sub-channels a11 is caused to flow into a turbulent flow state by the turbulent flow forming portion 91 (constituting the turbulent flow forming body 90) and flows through each of the sub-channels a 11. The fuel gas can enter the electrode layer 31 and the electrolyte layer 32 through the gas flow-allowing portion 1A. The fuel gas further advances through the inner flow path a1 together with the fuel gas having completed the electrochemical reaction, passes through the junction a13 and the second penetration portion 51, advances through the discharge passage 5 formed by the second annular seal portion 52, and is discharged from the first gas discharge portion 62 to the outside of the container 200 together with the fuel gas from the other electrochemical element a having completed the electrochemical reaction.

On the other hand, the air supplied from the second gas supply unit 71 can enter the flow portion a2 through the distribution chamber 9, and can enter the counter electrode layer 33 and the electrolyte layer 32. The air further moves along the electrochemical reaction unit 3 in the flow path a2 together with the air having completed the electrochemical reaction, and is discharged from the second gas discharge unit 72 to the outside of the container 200.

In accordance with the flow of the fuel gas and the air, the electric power generated in the electrochemical reaction section 3 is connected in series between the current collectors 81 and 82 by the contact between the electrochemical reaction section 3 of the adjacent electrochemical element a and the second plate-like body 2, and the synthesized output is extracted from the output section 8.

The structure of the electrochemical element laminate S will be described in detail later.

(5) Specific constitution of electrochemical element laminate S

Next, a specific configuration of the electrochemical element laminate S will be described. The electrochemical element laminate S is formed by laminating a plurality of electrochemical elements a.

The electrochemical element a will be described with reference to fig. 5 to 14.

(electrochemical element)

As shown in fig. 5 to 13, the electrochemical element a includes a plate-like support 10, and the plate-like support 10 includes an internal flow path a1 formed between the facing surfaces of the first plate-like body 1 and the second plate-like body 2.

The plate-like support 10 includes: a gas flow-permitting part 1A that allows gas to pass through at least a part of the first plate-like member 1 and the second plate-like member 2 constituting the plate-like support 10 over the inside of the plate-like support 10, that is, the inside flow path a1 and the outside; and an electrochemical reaction part 3 having a film-like electrode layer 31, a film-like electrolyte layer 32, and a film-like counter electrode layer 33 in the stated order in a state of covering all or a part of the gas flow-through allowing part 1A (see fig. 9 to 13).

In the present embodiment, the turbulence forming portion 91 (constituting the turbulence forming body 90) is provided in the sub-flow passage a11 among the internal flow passages a 1.

The plate-shaped support 10 has a first through-hole 41 on one end side, which forms a supply passage 4 for supplying a first gas, which is one of a reducing component gas such as a fuel gas and an oxidizing component gas such as air, to the inner passage a1 from outside in the surface penetration direction, and a second through-hole 51 on the other end side, which forms a discharge passage 5 for discharging the first gas flowing through the inner passage a1 to outside in the surface penetration direction of the plate-shaped support (see fig. 5, 7, 12, and 13, it should be noted that the supply passage 4 and the discharge passage 5 may be configured to be symmetrical).

(plate-shaped support)

The first plate-like member 1 supports the electrochemical reaction part 3 having the electrode layer 31, the electrolyte layer 32, and the counter electrode layer 33, and functions to maintain the strength of the electrochemical element a. As the material of the first plate-like body 1, a material excellent in electron conductivity, heat resistance, oxidation resistance, and corrosion resistance is used. For example, ferritic stainless steel, austenitic stainless steel, nickel-based alloy, and the like are used.

In particular, alloys containing chromium are suitable. In the present embodiment, the first plate-like member 1 is particularly preferably an Fe — Cr alloy containing 18 mass% or more and 25 mass% or less of Cr, an Fe — Cr alloy containing 0.05 mass% or more of Mn, an Fe — Cr alloy containing 0.15 mass% or more and 1.0 mass% or less of Ti, an Fe — Cr alloy containing 0.15 mass% or more and 1.0 mass% or less of Zr, an Fe — Cr alloy containing Ti and Zr and having a total content of Ti and Zr of 0.15 mass% or more and 1.0 mass% or less of Ti, and an Fe — Cr alloy containing 0.10 mass% or more and 1.0 mass% or less of Cu.

The second plate-like body 2 is welded and integrated at the peripheral edge 1a in a state of being overlapped with the first plate-like body 1, thereby constituting a plate-like support body 10 (see fig. 6 to 13). The second plate-like body 2 may be divided into a plurality of pieces with respect to the first plate-like body 1, and conversely, the first plate-like body 1 may be divided into a plurality of pieces with respect to the second plate-like body 2. In addition, in the integration, other means such as adhesion or fitting may be used instead of welding, and the integration may be performed in a portion other than the peripheral edge portion 1a as long as the internal flow path and the external area can be partitioned.

The first plate-like member 1 includes a gas flow allowing portion 1A, and the gas flow allowing portion 1A is formed by providing a plurality of through holes 11 penetrating through a front surface side and a rear surface side (see fig. 9 to 13). For example, the through-hole 11 may be provided in the first plate-like member 1 by laser processing or the like. The through-hole 11 has a function of allowing gas to pass from the surface on the back side to the surface on the front side of the first plate-like member 1. The gas flow-allowing portion 1A is preferably provided in a region smaller than the region of the first plate-like member 1 where the electrode layer 31 is provided.

A metal oxide layer 12 (described later, see fig. 14) is provided as a diffusion suppression layer on the surface of the first plate-like body 1. That is, a diffusion suppression layer is formed between the first plate-like body 1 and an electrode layer 31 described later. The metal oxide layer 12 is provided not only on the surface of the first plate-like body 1 exposed to the outside but also on the surface (interface) in contact with the electrode layer 31. Further, the through hole 11 may be provided on an inner surface thereof. The metal oxide layer 12 can suppress mutual diffusion of elements between the first plate-like member 1 and the electrode layer 31. For example, when a ferritic stainless steel containing chromium is used as the first plate-like body 1, the metal oxide layer 12 is mainly chromium oxide. The metal oxide layer 12 containing chromium oxide as a main component suppresses diffusion of chromium atoms and the like of the first plate-like body 1 into the electrode layer 31 and the electrolyte layer 32. The thickness of the metal oxide layer 12 may be set to a thickness that can achieve both high diffusion prevention performance and low resistance.

The metal oxide layer 12 can be formed by various means, and a method of oxidizing the surface of the first plate-like body 1 to produce a metal oxide is suitably used. The metal oxide layer 12 may be formed on the surface of the first plate-like body 1 by a spray coating method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spray coating method), a PVD method such as a sputtering method or a PLD method, a CVD method, or the like, or may be formed by plating or an oxidation treatment. Further, the metal oxide layer 12 may contain spinel or the like having high conductivity.

When a ferritic stainless steel material is used as the first plate-like member 1, the thermal expansion coefficient is close to that of YSZ (yttria-stabilized zirconia) or GDC (also referred to as gadolinium-doped ceria or CGO) which is a material of the electrode layer 31 or the electrolyte layer 32. Therefore, the electrochemical element a is also less likely to be damaged when temperature cycles of low and high temperatures are repeated. Therefore, the electrochemical device a having excellent long-term durability can be realized, which is preferable. The first plate-like body 1 has a plurality of through holes 11 provided through the front surface and the back surface. For example, the through-hole 11 may be provided in the first plate-like member 1 by mechanical, chemical, or optical piercing. The through-hole 11 has a function of allowing gas to pass from the surface on the back side to the surface on the front side of the first plate-like member 1. In order to impart gas permeability to the first plate-like member 1, a porous metal may be used. For example, sintered metal, foamed metal, or the like can be used for the first plate-like body 1.

The plate-like support (first plate-like body 1, second plate-like body 2)10 has an internal flow path a1 therein. The internal flow passage a1 is formed between the first plate-like body 1 and the second plate-like body 2. The internal flow path a1 has a plurality of sub flow paths a11 and a11 … … … in a region facing the gas flow allowing portion 1A of the first plate-like body 1. The plurality of sub-channels a11, a11 … … … are formed by processing the second plate-like body 2 into a corrugated plate shape. The plurality of sub-flow paths a11, a11 … … … extend from one end side to the other end side (first direction side), that is, in the flow direction of the first gas, in the direction along the plate-shaped surface of the plate-shaped support 10. The plurality of sub-channels a11, a11 … … … are isolated from each other in a direction (second direction) intersecting from one end side to the other end side in a direction along the plate-shaped surface of the plate-shaped support 10.

The second plate-like body 2 is formed into a corrugated plate shape on both the front and back surfaces, and the surface opposite to the surface partitioning the internal flow path a1 is electrically connected to the electrochemical reaction part 3 of the adjacent electrochemical element a.

The passage formed in the vicinity of the portion where the second plate-like body 2 having the corrugated shape contacts the first plate-like body 1 functions as the flow portion a 2.

To explain this, a plurality of the sub-flow paths a11 are provided in parallel along the long sides of the plate-like support 10 formed in a rectangular shape, and constitute an internal flow path a1 extending from the supply path 4 provided at one end to the discharge path 5 provided at the other end. The distribution portion a12 is provided in which the connection portion between the first penetration portion 41 and the internal flow path a1 is expanded downward from the portion in contact with the first plate-shaped body 1, the first gas supplied from the first penetration portion 41 is distributed to the sub-flow paths a11 (see fig. 5), and the merging portion a13 is provided in which the connection portion between the second penetration portion 51 and the internal flow path a1 is expanded downward from the portion in contact with the first plate-shaped body 1, and the first gas flowing through the sub-flow paths a11 is collected and introduced into the second penetration portion 51 (see fig. 5, 7, 8, 10 to 13, and it should be noted that the configuration of the supply path 4 and the discharge path 5 and the like can be understood as being the same configuration in a symmetrical manner). The material of the second plate-like body 2 is preferably a heat-resistant metal, and from the viewpoint of reducing the difference in thermal expansion between the second plate-like body and the first plate-like body 1 and ensuring reliability of the bonding property such as soldering, it is more preferable to use the same material as the first plate-like body 1.

The plate-like support 10 formed of the first plate-like body 1 and the second plate-like body 2 as described above has the electrode layer 31, the electrolyte layer 32, the counter electrode layer 33, and the like formed on the upper surface thereof. That is, the electrode layer 31, the electrolyte layer 32, the counter electrode layer 33, and the like are supported by the plate-shaped support 10, and the electrochemical element a having high strength and excellent reliability and durability can be realized. Further, the metallic plate-like support 10 is preferable because it is excellent in workability. Further, since the plate-shaped support 10 having high strength can be obtained even when an inexpensive metal is used for the plate-shaped support 10, the expensive electrode layer 31, the electrolyte layer 32, and the like can be made thin, and the electrochemical element a having low cost and suppressed material cost and processing cost can be realized, which is preferable.

(turbulence forming body)

In the present embodiment, the turbulence forming body 90 is provided in the internal flow path a1 as shown in fig. 4, 9 to 14, and 16 to 18. Further, the turbulence forming body 90 is formed by the turbulence forming portion 91 provided in the sub-flow passage a11, among the internal flow passage a 1. The turbulent flow forming portion 91 forms the first gas flowing through the secondary flow path a11 into a turbulent flow state.

Here, the turbulent state in the present embodiment means a state in which the flow of the fluid in the flow path is not parallel to the inner wall of the flow path. In the turbulent flow state, at least a part of the fluid is swirled. On the other hand, the laminar flow state is a state in which the flow of the fluid in the flow path has a substantially regular flow line in parallel with the inner wall of the flow path, unlike the turbulent flow state.

The flow state in the flow path can be expressed by the reynolds number, which is a turbulent flow when the reynolds number is high and a laminar flow when the reynolds number is low. The Reynolds number (Re) is defined by the following formula.

Re=D×u×ρ/μ。

Here, D is a channel diameter (m), u: average flow velocity (m/sec) of fluid, ρ: density of fluid (kg/m)³) And μ is the viscosity (kg/(m seed) of the fluid).

When the fluid is a reducing component gas such as a fuel gas or an oxidizing component gas such as air, Re in the case where the gas is in a turbulent state is about Re > 2800, and if a compact design is desired, the flow channel diameter D is small, and therefore it is often difficult to increase this value.

As shown in fig. 9 to 14 and 16 to 18, the turbulent flow forming portion 91 is provided adjacent to the lower surface of the gas flow allowing portion 1A in the secondary flow path a 11. However, the first gas flowing through the secondary flow path a11 may be caused to flow in the extending direction of the secondary flow path a11 while being caused to flow in a turbulent flow state, and the position of the turbulent flow forming portion 91 is not limited to this. For example, the turbulent flow forming portion 91 may be provided along the upper surface of the second plate-like body 2 facing the secondary flow path a 11. The turbulent flow forming portion 91 may be provided in the central portion between the lower surface of the gas flow permitting portion 1A and the upper surface of the second plate-like body 2 facing the sub flow path a 11. Further, the turbulent flow forming portion 91 may be provided so as to fill the inside of the secondary flow path a11 as long as the first gas can flow in the extending direction of the secondary flow path a 11.

The turbulent flow forming portion 91 is not limited to this, and may be a mesh body provided in the sub-flow path a11 along the plane of the first plate-like body 1 as shown in fig. 9 to 14. The first gas can be made to be in a turbulent state by flowing the first gas through the mesh body. The mesh body is configured to be able to not only bring the first gas into a turbulent state, but also to be able to circulate the first gas along the sub-passage a 11.

Examples of the mesh body include a metal mesh, a porous drawn metal, a porous metal (foamed metal), a metal felt, a pressed metal, and a 3D fabric.

The expanded metal is a metal having a flat plate shape and is processed into a mesh having, for example, a diamond shape by drawing. The porous metal has bubbles constituting a lattice, and is a metal having a small bulk density. The metal felt is formed by stacking and sintering metal fibers, and is processed in such a manner that a mesh is formed between the fibers. The punching metal is processed into a mesh shape by punching out holes from a flat metal plate. The 3D fabric is processed to have a mesh by, for example, a pair of flat plate-like metals having a mesh and metals woven in a wave shape between them.

The first gas may be in a turbulent flow state by the mesh body, and the shape thereof is not particularly limited. The mesh body is, for example, flat. The flat plate-like mesh body may be disposed along the flat plate-like support 10.

The turbulent flow forming portion 91 is not limited to this, and examples thereof include granular particles provided in the secondary flow path a11 as shown in fig. 16 to 18. The first gas collides with the particulate matter, whereby the first gas can be brought into a turbulent flow state. The granular particles are regularly or irregularly arranged in the secondary flow path a 11. The granular particles are so large that they can be inserted into the sub-passage a11 and the first gas can flow in the extending direction of the sub-passage a 11. The granular particles may be filled in the sub-flow path a11 or fixed to the upper surface of the second plate-like body 2.

As a material of the turbulent flow forming portion 91 formed of the mesh body, the granular body, or the like, for example, austenitic stainless steel such as SUS316 or SUS304, ferritic stainless steel such as SUS430, or nichrome-based heat-resistant alloy can be used. Further, the material of the turbulence forming portion 91 may be the same kind and the same as the material of the plate-shaped support body 10. Further, when the sheet is formed of a flat plate, the sheet is not limited to a metal, and may be formed of a conductive inorganic material such as conductive glass. When the particles are formed of a metal, a conductive material, or a non-conductive material such as ceramic may be used.

Further, as a material constituting the turbulent flow forming portion 91 of the turbulent flow forming body 90, a material excellent in electron conductivity, heat resistance, oxidation resistance, and corrosion resistance can be used. For example, ferritic stainless steel, austenitic stainless steel, nickel-based alloy, and the like can be used. In particular, alloys containing chromium are suitable. In the present embodiment, the first plate-like member 1 is particularly preferably an Fe — Cr alloy containing 18 mass% or more and 25 mass% or less of Cr, an Fe — Cr alloy containing 0.05 mass% or more of Mn, an Fe — Cr alloy containing 0.15 mass% or more and 1.0 mass% or less of Ti, an Fe — Cr alloy containing 0.15 mass% or more and 1.0 mass% or less of Zr, an Fe — Cr alloy containing Ti and Zr and having a total content of Ti and Zr of 0.15 mass% or more and 1.0 mass% or less of Ti, and an Fe — Cr alloy containing 0.10 mass% or more and 1.0 mass% or less of Cu.

With the above-described characteristic configuration, the first gas flows through the sub-flow path a11 between the first plate-like member 1 and the second plate-like member 2. Since the turbulent flow forming portion 91 that forms a turbulent flow state of the first gas is provided in the secondary flow path a11, the first gas is likely to form a turbulent flow state in the secondary flow path a 11. In the turbulent flow state, the fluid flows through the flow path in a state where at least a part of the fluid swirls. Therefore, the fluid in a turbulent state flows mainly in the flow path direction in the flow path, and also flows in a direction different from the flow path direction. Therefore, the first gas easily permeates from the sub-flow passage a11 to the outside through the gas flow allowing portion 1A formed in the first plate-like body 1 while traveling along the plane of the first plate-like body 1 and the plane of the second plate-like body 2 forming the sub-flow passage a11 in the sub-flow passage a 11. This improves the efficiency of supplying the first gas to the electrochemical reaction parts 3 formed on the outer surfaces of the plate-like support 10, promotes the electrochemical reaction in the electrochemical reaction parts 3, and improves the power generation efficiency.

In particular, as the electrochemical element a is miniaturized, the first plate-like body 1 and the second plate-like body 2 forming the sub-flow path a11 become narrow and flat, and the first gas may be in a laminar state traveling along the plane of the plate-like support 10, but the first gas is likely to be in a turbulent state due to the presence of the turbulent flow forming portion 91. When the power generation output of electrochemical element a having electrochemical reaction unit 3 is reduced, the amount of first gas supplied to secondary flow path a11 is adjusted to be small. As described above, when the amount of the first gas flowing through the sub-flow passage a11 is small, the first gas may be in a laminar state traveling along the plane of the plate-like support 10. However, by the presence of the turbulence forming portion 91, the first gas is easily formed into a turbulent state. Therefore, the efficiency of supplying the first gas from the secondary flow path a11 to the electrochemical reaction unit 3 through the gas flow-allowing unit 1A is improved.

(electrochemical reaction section)

(electrode layer)

As shown in fig. 9 to 14, the electrode layer 31 may be provided in a thin layer in a region larger than the region in which the through-hole 11 is provided, the region being the front surface side surface of the first plate-like member 1. When the thickness is thin, the thickness may be, for example, about 1 μm to 100 μm, preferably 5 μm to 50 μm. If the thickness is set to such a value, it is possible to ensure sufficient electrode performance while reducing the amount of expensive electrode layer material to reduce the cost. The entire region in which the through-hole 11 is provided is covered with the electrode layer 31. That is, the through-hole 11 is formed inside the region of the first plate-like body 1 where the electrode layer 31 is formed. In other words, all the through-holes 11 are disposed facing the electrode layer 31.

The electrode layer 31 has a plurality of micropores in its inner portion and surface so as to have gas permeability.

That is, the electrode layer 31 is formed as a porous layer. The electrode layer 31 is formed, for example, so that the density thereof becomes 30% or more and less than 80%. The size of the micropores can be appropriately selected to be suitable for a smooth reaction when an electrochemical reaction is performed. The density is a ratio of a material constituting a layer in a space, and can be expressed as (1-porosity), and is the same as the relative density.

As the material of the electrode layer 31, for example, NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO, etc. can be used₂、Cu-CeO₂And the like.

In these examples, GDC, YSZ, CeO may be used₂Referred to as composite aggregate. The electrode layer 31 is preferably formed by a low-temperature firing method (for example, a wet method using a firing treatment in a low-temperature region in which a firing treatment in a high-temperature region higher than 1100 ℃ is not performed), a spraying method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. By these processes that can be used in a low temperature region, a good electrode layer 31 is obtained without using, for example, firing in a high temperature region higher than 1100 ℃. Therefore, do notIt is preferable to damage the first plate-like member 1, and to suppress interdiffusion of elements of the first plate-like member 1 and the electrode layer 31, and to realize the electrochemical device a having excellent durability. Further, the use of the low-temperature calcination method is more preferable because the treatment of the raw material becomes easy.

(intermediate layer)

The intermediate layer 34 may be formed in a thin layer on the electrode layer 31 so as to cover the electrode layer 31. When the thickness is thin, the thickness may be, for example, about 1 μm to 100 μm, preferably about 2 μm to 50 μm, and more preferably about 4 μm to 25 μm.

If the thickness is set to such a value, sufficient performance can be ensured while reducing the amount of material used for the expensive intermediate layer 34 to reduce the cost. As a material of the intermediate layer 34, for example, YSZ (yttria-stabilized zirconia), SSZ (scandium-stabilized zirconia), GDC (gadolinium-doped ceria), YDC (yttrium-doped ceria), SDC (samarium-doped ceria), or the like can be used. Cerium oxide-based ceramics are particularly suitable.

The intermediate layer 34 is preferably formed by a low-temperature firing method (for example, a wet method using a firing treatment in a low-temperature region in which a firing treatment in a high-temperature region higher than 1100 ℃ is not performed), a spraying method (a method such as a sputtering method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. By these film forming processes that can be used in a low temperature region, the intermediate layer 34 is obtained without using, for example, calcination in a high temperature region higher than 1100 ℃. Therefore, mutual diffusion of elements of the first plate-like member 1 and the electrode layer 31 can be suppressed without damaging the first plate-like member 1, and an electrochemical element a having excellent durability can be realized. Further, the use of the low-temperature calcination method is more preferable because the treatment of the raw material becomes easy.

The intermediate layer 34 preferably has oxygen ion (oxide ion) conductivity. Further, it is more preferable if the mixed conductivity of oxygen ions (oxide ions) and electrons is present. The intermediate layer 34 having these properties is suitable for application to the electrochemical element a.

(electrolyte layer)

As shown in fig. 9 to 14, the electrolyte layer 32 is formed in a thin layer on the intermediate layer 34 in a state of covering the electrode layer 31 and the intermediate layer 34. Further, the film may be formed in a thin film state having a thickness of 10 μm or less. In detail, the electrolyte layer 32 is provided across (straddling) the intermediate layer 34 and the first plate-like body 1. With such a configuration, the electrolyte layer 32 is joined to the first plate-like member 1, whereby the entire electrochemical device can be made to have excellent firmness.

As shown in fig. 9, the electrolyte layer 32 may be provided in a region that is a surface on the front side of the first plate-like body 1 and that is larger than the region in which the through-hole 11 is provided. That is, the through-hole 11 is formed inside the region of the first plate-like body 1 where the electrolyte layer 32 is formed.

Further, around the electrolyte layer 32, leakage of gas from the electrode layer 31 and the intermediate layer (not shown) can be suppressed. When electrochemical element a is used as a component of the SOFC, gas is supplied to electrode layer 31 from the back surface side of first plate-like member 1 through-hole 11 during operation of the SOFC. At the portion where the electrolyte layer 32 contacts the first plate-like body 1, leakage of gas can be suppressed without providing another member such as a gasket.

In the present embodiment, the periphery of the electrode layer 31 is completely covered with the electrolyte layer 32, but the electrolyte layer 32 may be provided on the upper portions of the electrode layer 31 and the intermediate layer 34, and a gasket or the like may be provided on the periphery.

As the material of the electrolyte layer 32, an oxygen ion conducting electrolyte material such as YSZ (yttria-stabilized zirconia), SSZ (scandium-stabilized zirconia), GDC (gadolinium-doped ceria), YDC (yttrium-doped ceria), SDC (samarium-doped ceria), LSGM (strontium-magnesium-added lanthanum gallate), or a hydrogen ion conducting electrolyte material such as a perovskite-type oxide can be used.

Zirconia ceramics are particularly suitable. If the electrolyte layer 32 is made of zirconia-based ceramic, the operation temperature of the SOFC using the electrochemical element a can be set higher than that of cerium oxide-based ceramic and various hydrogen ion conductive materials. For example, when the electrochemical element a is used for an SOFC, if a system is used in which a material capable of exhibiting high electrolyte performance even in a high-temperature region of about 650 ℃ or higher, such as YSZ, is used as the material of the electrolyte layer 32, a hydrocarbon-based raw fuel such as town gas or LPG is used as the raw fuel of the system, and the raw fuel is converted to the anode gas of the SOFC by steam reforming or the like, it is possible to construct a highly efficient SOFC system in which the heat generated in the cell stack of the SOFC is used for reforming the raw fuel gas.

The electrolyte layer 32 is preferably formed by a low-temperature firing method (for example, a wet method using a firing treatment in a low-temperature region in which the firing treatment is not performed in a high-temperature region of more than 1100 ℃), a spraying method (a method such as a sputtering method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD (chemical vapor deposition) method, or the like. By these film forming processes that can be used in a low temperature region, the electrolyte layer 32 that is dense and high in gas tightness and gas barrier properties is obtained without using, for example, calcination in a high temperature region higher than 1100 ℃. Therefore, damage to the first plate-like member 1 can be suppressed, interdiffusion of elements of the first plate-like member 1 and the electrode layer 31 can be suppressed, and the electrochemical element a having excellent performance and durability can be realized. In particular, if a low-temperature calcination method, a spray method, or the like is used, it is preferable because a low-cost element can be realized. Further, if the spray coating method is used, a dense electrolyte layer having high gas tightness and gas barrier properties can be easily obtained in a low temperature region, and therefore, it is more preferable.

The electrolyte layer 32 is densely configured to block gas leakage of the anode gas and the cathode gas and to exhibit high ion conductivity. The density of the electrolyte layer 32 is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more. In the case where the electrolyte layer 32 is a uniform layer, the compactness thereof is preferably 95% or more, and more preferably 98% or more. In the case where the electrolyte layer 32 is formed in a plurality of layered forms, at least a portion thereof is preferably included in a layer having a density of 98% or more (dense electrolyte layer), and more preferably included in a layer having a density of 99% or more (dense electrolyte layer). The reason for this is that if such a dense electrolyte layer is included in a part of the electrolyte layer, even when the electrolyte layer is formed in a plurality of layers, the electrolyte layer can be easily formed to be dense and to have high gas tightness and gas barrier properties.

(reaction preventive layer)

The reaction preventing layer 35 may be formed in a thin layer state on the electrolyte layer 32. When the thickness is thin, the thickness may be, for example, about 1 μm to 100 μm, preferably about 2 μm to 50 μm, and more preferably about 3 μm to 15 μm. If the thickness is set to such a value, sufficient performance can be ensured while reducing the amount of expensive anti-reflective layer material to reduce the cost. As the material of the reaction preventing layer, any material may be used as long as it can prevent the reaction between the components of the electrolyte layer 32 and the components of the counter electrode layer 33, and for example, a cerium oxide-based material or the like is used. Further, as the material of the reaction-preventing layer 35, a material containing at least 1 kind of element selected from Sm, Gd, and Y is suitably used. At least 1 element selected from the group consisting of Sm, Gd, and Y may be contained, and the total content of these elements is 1.0 mass% or more and 10 mass% or less. By introducing the reaction-preventing layer 35 between the electrolyte layer 32 and the counter electrode layer 33, the reaction between the constituent material of the counter electrode layer 33 and the constituent material of the electrolyte layer 32 is effectively suppressed, and the long-term stability of the performance of the electrochemical element a can be improved. The formation of the reaction-preventing layer 35 is preferable because if a method capable of forming at a processing temperature of 1100 ℃ or lower is appropriately used, damage to the first plate-like member 1 can be suppressed, interdiffusion of elements of the first plate-like member 1 and the electrode layer 31 can be suppressed, and an electrochemical element a having excellent performance and durability can be realized. For example, the sintering can be performed by a low-temperature sintering method (for example, a wet method using a sintering treatment in a low-temperature region where a sintering treatment in a high-temperature region of more than 1100 ℃ is not performed), a spray method (a method such as a spray coating method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, and a cold spray method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In particular, if a low-temperature calcination method, a spray method, or the like is used, it is preferable because a low-cost element can be realized. Further, the use of the low-temperature calcination method is more preferable because the treatment of the raw material becomes easy.

(counter electrode layer)

As shown in fig. 9 to 14, the counter electrode layer 33 may be formed in a thin layer on the electrolyte layer 32 or the anti-reflection layer 35. When the thickness is thin, the thickness may be, for example, about 1 μm to 100 μm, preferably 5 μm to 50 μm. If the thickness is set to such a value, it is possible to secure sufficient electrode performance while reducing the amount of expensive counter electrode layer material to reduce the cost. As the material of the counter electrode layer 33, for example, a composite oxide such as LSCF or LSM, a cerium oxide-based oxide, and a mixture thereof can be used. In particular, the counter electrode layer 33 preferably contains a perovskite type oxide containing 2 or more elements selected from La, Sr, Sm, Mn, Co, and Fe. The counter electrode layer 33 formed using the above-described material functions as a cathode.

It should be noted that if the formation of the electrode layer 33 is carried out by using a method capable of forming at a processing temperature of 1100 ℃ or lower as appropriate, damage to the first plate-shaped body 1 can be suppressed, and interdiffusion of elements of the first plate-shaped body 1 and the electrode layer 31 can be suppressed, so that an electrochemical element a having excellent performance and durability can be realized. For example, the sintering can be carried out by a low-temperature sintering method (for example, a wet method using a sintering treatment in a low-temperature region where a sintering treatment in a high-temperature region of more than 1100 ℃ is not carried out), a spray method (a method such as a spray coating method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spray method), a PDV method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like as appropriate. In particular, if a low-temperature calcination method, a spray method, or the like is used, it is preferable because a low-cost element can be realized. Further, the use of the low-temperature calcination method is more preferable because the treatment of the raw material becomes easy.

By configuring the electrochemical reaction section 3 as described above, the electrochemical element a can be used as a power generation cell of a solid oxide fuel cell when the electrochemical reaction section 3 is caused to function as a fuel cell (electrochemical power generation cell). For example, a fuel gas containing a hydrogen gas as a first gas is supplied to the electrode layer 31 from the back surface side of the first plate-like body 1 through the through-hole 11, and air as a second gas is supplied to the counter electrode layer 33 serving as a counter electrode of the electrode layer 31, and the operating temperature is maintained at, for example, about 700 ℃. Thus, oxygen O contained in the air in the counter electrode layer 33₂And an electron e^-React to generate oxygen ions O^2-. The oxygen ion O^2-Moves to the electrode layer 31 through the electrolyte layer 32. In the electrode layer 31, hydrogen H contained in the fuel gas supplied₂With oxygen ions O^2-Reacting to form water H₂O and an electron e^-。

In the case of using a hydrogen ion-conducting electrolyte material in the electrolyte layer 32, hydrogen H contained in the fuel gas flowing through the electrode layer 31₂Liberation of electrons e^-To generate hydrogen ions H⁺. The hydrogen ion H⁺Moves to the counter electrode layer 33 through the electrolyte layer 32. Oxygen O contained in air in the counter electrode layer 33₂With hydrogen ions H⁺Electron e^-Reacting to form water H₂O。

Through the above reaction, an electromotive force is generated as an electrochemical output between the electrode layer 31 and the counter electrode layer 33. In this case, the electrode layer 31 functions as a fuel electrode (anode) of the fuel cell, and the counter electrode layer 33 functions as an air electrode (cathode).

Note that, although omitted in fig. 9 to 13, the electrochemical reaction section 3 in the present embodiment has an intermediate layer 34 between the electrode layer 31 and the electrolyte layer 32, as shown in fig. 14. Further, a reaction preventing layer 35 is provided between the electrolyte layer 32 and the counter electrode layer 33.

(evaluation of electrochemical element A having turbulence-forming body)

In 1 electrochemical element a having the turbulent flow forming body 90 of the present embodiment, the power generation efficiency was evaluated. As a comparative example, 1 electrochemical element having no turbulence forming body 90 was used.

In both the electrochemical device a of the present embodiment and the electrochemical device of the comparative example, 1 electrochemical device was operated with a power generation output of 18W. In 1 electrochemical element of the comparative example having no turbulent flow former 90, the fuel utilization rate was 72.5%. On the other hand, in the 1 electrochemical element a having the turbulent flow forming body 90 of the present embodiment, the fuel utilization rate is 80.0%.

The fuel utilization rate is calculated from the proportion of the fuel gas consumed by the power generation by the electrochemical reaction in the electrochemical element with respect to the fuel gas supplied to the electrochemical element.

As described above, in electrochemical device a of the present embodiment having turbulence forming body 90, the fuel utilization rate is improved as compared with the electrochemical device of the comparative example not having turbulence forming body 90. The reason for this is considered to be that the fuel gas flowing through the internal flow path can be supplied from the sub-flow path a11 of the internal flow path a1 to the electrochemical reaction unit 3 through the gas flow-allowing unit 1A. Therefore, by providing the turbulent flow forming body 90, the power generation efficiency by the electrochemical reaction in the electrochemical device can be improved by 1 or more (10.3%).

(method of manufacturing electrochemical reaction part)

Next, a method for producing the electrochemical reaction part 3 will be described. Note that, in fig. 9 to 13, the following description of the intermediate layer 34 and the anti-reflection layer 35 is omitted, and therefore, the description will be mainly given using fig. 14.

(electrode layer Forming step)

In the electrode layer forming step, the electrode layer 31 is formed in a thin film state in a wider region than the region in which the through-holes 11 are provided on the front surface side of the first plate-like body 1. The through-hole 11 of the first plate-like body 1 may be provided by laser processing or the like. As described above, the electrode layer 31 can be formed by a low-temperature firing method (a wet method in which firing treatment is performed in a low-temperature region of 1100 ℃ or lower), a spraying method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In the case of using either method, it is desirable to perform the method at a temperature of 1100 ℃ or lower in order to suppress deterioration of the first plate-like body 1.

When the electrode layer forming step is performed by a low-temperature firing method, the electrode layer forming step is specifically performed as in the following example. First, a material paste is prepared by mixing a material powder of the electrode layer 31 with a solvent (dispersion medium), applied to the front surface side of the first plate-like body 1, and fired at 800 to 1100 ℃.

(diffusion suppressing layer formation step)

In the firing step in the electrode layer forming step described above, the metal oxide layer 12 (diffusion suppression layer) is formed on the surface of the first plate-like body 1. In the above-described calcination step, if a calcination step is included in which the calcination atmosphere is set to an atmosphere having a low oxygen partial pressure, the interdiffusion suppressing effect of the elements is high, and a good-quality metal oxide layer 12 (diffusion suppression layer) having a low resistance value is preferably formed. The diffusion-suppressing layer formation step may be separately included, including a case where the electrode layer formation step is a coating method without performing firing. In any case, it is desirable to carry out the treatment at a treatment temperature of 1100 ℃ or less at which damage to the first plate-like body 1 can be suppressed.

(intermediate layer formation step)

In the intermediate layer forming step, the intermediate layer 34 is formed in a thin layer on the electrode layer 31 so as to cover the electrode layer 31. As described above, the intermediate layer 34 can be formed by a low-temperature firing method (a wet method in which firing treatment is performed in a low-temperature region of 1100 ℃ or lower), a spraying method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In the case of using either method, it is desirable to perform the method at a temperature of 1100 ℃ or lower in order to suppress deterioration of the first plate-like body 1.

When the intermediate layer formation step is performed by a low-temperature firing method, the intermediate layer formation step is specifically performed as in the following example.

First, a material paste is prepared by mixing the material powder of the intermediate layer 34 and a solvent (dispersion medium), and is applied to the front surface side of the first plate-like body 1. The intermediate layer 34 is compression molded (intermediate layer smoothing step) and fired at a temperature of 1100 ℃ or lower (intermediate layer firing step). The calendering of the intermediate layer 34 can be performed by, for example, CIP (Cold Isostatic Pressing) molding, roll press molding, RIP (Rubber Isostatic Pressing) molding, or the like. Further, it is suitable if the calcination of the intermediate layer 34 is performed at a temperature of 800 ℃ or higher and 1100 ℃ or lower. The reason for this is that if the temperature is set to such a temperature, the intermediate layer 34 having high strength can be formed while suppressing damage and deterioration of the first plate-like member 1. In addition, the calcination of the intermediate layer 34 is more preferable if it is performed at 1050 ℃ or less, and is further preferable if it is performed at 1000 ℃ or less. The reason for this is that the lower the firing temperature of the intermediate layer 34, the more the electrochemical element a can be formed while further suppressing damage and deterioration of the first plate-like member 1. In addition, the order of the intermediate layer smoothing step and the intermediate layer calcining step may be replaced.

The intermediate layer smoothing step may be performed by performing stretch forming, leveling treatment, surface cutting/polishing treatment, and the like.

(electrolyte layer formation step)

In the electrolyte layer forming step, the electrolyte layer 32 is formed in a thin layer on the intermediate layer 34 in a state of covering the electrode layer 31 and the intermediate layer 34. The film may be formed in a thin film having a thickness of 10 μm or less. As described above, the electrolyte layer 32 can be formed by a low-temperature firing method (a wet method in which firing treatment is performed in a low-temperature region of 1100 ℃ or lower), a spraying method (a method such as a sputtering method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In the case of using either method, it is desirable to perform the method at a temperature of 1100 ℃ or lower in order to suppress deterioration of the first plate-like body 1.

In order to form the electrolyte layer 32 of good quality which is dense and high in airtightness and gas barrier performance in a temperature region of 1100 ℃ or less, it is desirable to perform the electrolyte layer forming step by a spray coating method. In this case, the material of the electrolyte layer 32 is ejected toward the intermediate layer 34 on the first plate-like body 1 to form the electrolyte layer 32.

(anti-Forming step)

In the reaction-prevention layer formation step, the anti-reaction layer 35 is formed in a thin layer state on the electrolyte layer 32. As described above, the anti-reaction layer 35 can be formed by a low-temperature firing method (a wet method in which firing treatment is performed in a low-temperature region of 1100 ℃ or lower), a spraying method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In the case of using either method, it is desirable to perform the method at a temperature of 1100 ℃ or lower in order to suppress deterioration of the first plate-like body 1. In order to flatten the upper surface of the anti-reaction layer 35, for example, the surface may be subjected to leveling treatment after the formation of the anti-reaction layer 35, or may be subjected to cutting/polishing treatment after wet formation and before calcination.

(counter electrode layer formation step)

In the counter electrode layer forming step, the counter electrode layer 33 is formed in a thin layer state on the anti-reflection layer 35. As described above, the electrode layer 33 can be formed by a low-temperature firing method (a wet method in which firing treatment is performed in a low-temperature region of 1100 ℃ or lower), a spraying method (a method such as a thermal spraying method, an aerosol deposition method, an aerosol vapor deposition method, a powder spray deposition method, a particle spray deposition method, or a cold spraying method), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. In the case of using either method, it is desirable to perform the method at a temperature of 1100 ℃ or lower in order to suppress deterioration of the first plate-like body 1.

In the above manner, the electrochemical reaction section 3 can be manufactured.

In addition, the electrochemical reaction portion 3 may be provided without one or both of the intermediate layer 34 and the anti-reaction layer 35. That is, the electrode layer 31 may be formed in contact with the electrolyte layer 32, or the electrolyte layer 32 may be formed in contact with the counter electrode layer 33. In this case, in the above-described manufacturing method, the intermediate layer forming step and the anti-reflection layer forming step are omitted. In addition, a step of forming another layer or a plurality of layers of the same kind may be added, and in any case, it is desirable to perform the forming at a temperature of 1100 ℃.

(electrochemical element laminate)

As shown in fig. 4, the electrochemical element laminate S may be configured by laminating a plurality of electrochemical elements a in a predetermined lamination direction. The adjacent electrochemical elements a are arranged such that the plate-shaped support 10 constituting one electrochemical element a (first electrochemical element a) faces the plate-shaped support 10 constituting the other electrochemical element a (second electrochemical element a).

For example, one electrochemical element a (first electrochemical element a) includes a plate-like support 10 having a first plate-like body 1 and a second plate-like body 2, in which electrochemical reaction parts 3 are arranged. Similarly, the plate-shaped support 10 of the second electrochemical element a adjacent to the first electrochemical element a in the downward direction (first direction) and in the upward direction (second direction) includes the plate-shaped support 10 having the first plate-shaped body 1 and the second plate-shaped body 2, in which the electrochemical reaction section 3 is disposed.

The outer surface of the second plate-like body 2 of the first electrochemical element a is electrically connected to the outer surface of the first plate-like body 1 of the second electrochemical element a adjacent in the upper direction. Further, between the outer surface of the second plate-like body 2 of the first electrochemical element a and the outer surface of the first plate-like body 1 of the second electrochemical element a adjacent in the upper direction, a flow portion a2 through which the second gas flows is formed along both the outer surfaces.

Further, the outer surface of the first plate-like body 1 of the first electrochemical element a is electrically connected to the outer surface of the second plate-like body 2 of the second electrochemical element a adjacent in the lower direction. A sub-flow path a11 (a part of the internal flow path a1) through which the first gas flows is formed between the outer surface of the first plate-like body 1 of the first electrochemical element a and the outer surface of the second plate-like body 2 of the second electrochemical element a adjacent in the lower direction, along the outer surfaces.

For the electrical connection, a method of simply bringing the electrically conductive surface portions into contact with each other, applying a surface pressure to the contact surface, or reducing the contact resistance through a highly electrically conductive material, or the like can be employed.

The turbulent flow forming portion 91 is provided in the secondary flow path a11 as described above.

The plurality of electrochemical elements a are stacked. Specifically, the rectangular electrochemical elements are stacked in a state in which the first penetration portion 41 at one end portion is aligned with the second penetration portion 51 at the other end portion, and the electrochemical reaction portions of the respective electrochemical elements face upward. Further, a first annular seal portion 42 is provided between the first penetration portions 41, and a second annular seal portion 52 is provided between the second penetration portions 51.

The plate-like support 10 has a first through-hole 41 formed at one end in the longitudinal direction of the rectangular plate-like support 10, and the first through-hole forms a first gas supply passage 4 for supplying the first gas, which is one of the reducing component gas and the oxidizing component gas, to the internal flow passage a1 from the outside in the surface through-hole direction. The flow passage a2 includes a first annular seal 42 as an annular seal that separates the first through-hole 41 formed in each of the two outer surfaces of the plate-like support 10 from the flow passage a 2. Further, the first penetrating portion 41 and the first annular seal portion 42 form the supply passage 4 for supplying the first gas to the internal flow passage a 1. In addition, the annular bulging portion a is provided on the surface of the first plate-like body 1 opposite to the internal flow path a1 around the portion of the first plate-like body 1 in contact with the first annular seal portion 42, so that the first annular seal portion 42 can be easily positioned in the direction along the surface of the first plate-like body 1.

The plate-like support 10 has a second penetration portion 51 on the other end side, and forms a discharge passage 5 for discharging the first gas flowing through the internal flow passage a1 to the outside in the penetration direction of the surface of the plate-like support 10. The second penetration portion 51 is configured to allow the first gas to flow therethrough in a state of being isolated from the second gas, and includes a second annular seal portion 52 as an annular seal portion in the flow portion a2, the second penetration portion 51 being formed on each of the two outer surfaces of the plate-shaped support 10, and the flow portion a 2. The second penetrating portion 51 and the second annular seal portion 52 form a discharge passage 5 that discharges the first gas flowing through the internal flow path a 1.

The first and second annular seal portions 42 and 52 are made of a ceramic material such as alumina, mica, or an insulating material such as a metal covering these materials, and function as insulating seal portions for electrically insulating adjacent electrochemical elements from each other.

(6) Energy system and electrochemical device

Next, an energy system and an electrochemical device will be described with reference to fig. 15.

The energy system Z includes an electrochemical device 100 and a heat exchanger 190 as an exhaust heat utilization unit that reuses heat discharged from the electrochemical device 100.

The electrochemical device 100 includes an electrochemical module M, a fuel supply module, and an inverter (an example of a power converter) 104 as an output unit 8 that extracts electric power from the electrochemical module M. The fuel supply module includes a desulfurizer 101, a gasifier 106, and a reformer 102, and has a fuel supply unit 103 that supplies a fuel gas containing a reducing component to the electrochemical module M. In this case, the reformer 102 forms a fuel converter.

Specifically, the electrochemical device 100 includes a desulfurizer 101, a reforming water tank 105, a gasifier 106, a reformer 102, a blower 107, a combustion unit 108, an inverter 104, a control unit 110, and an electrochemical module M.

The desulfurizer 101 removes (desulfurizes) sulfur compound components contained in a hydrocarbon-based raw fuel such as a town gas. When the raw fuel contains a sulfur compound, the desulfurizer 101 can suppress adverse effects on the reformer 102 or the electrochemical element a due to the sulfur compound. The vaporizer 106 generates steam from the reformate supplied from the reformate tank 105. The reformer 102 steam-reforms the raw fuel desulfurized by the desulfurizer 101 using the steam generated by the gasifier 106 to generate a reformed gas containing hydrogen.

Electrochemical module M generates electricity by performing an electrochemical reaction using the reformed gas supplied from reformer 102 and air supplied from blower 107. The combustion section 108 mixes the reaction exhaust gas discharged from the electrochemical module M with air, and combusts combustible components in the reaction exhaust gas.

The inverter 104 adjusts the output power of the electrochemical module M to the same voltage and the same frequency as the power received from the commercial system (not shown). The control unit 110 controls the operation of the electrochemical device 100 and the energy system Z.

The reformer 102 performs reforming processing of the raw fuel using combustion heat generated by combustion of the reaction exhaust gas in the combustion section 108.

The raw fuel is supplied to the desulfurizer 101 through the raw fuel supply line 112 by the operation of the booster pump 111. The reformed water in the reformed water tank 105 is supplied to the vaporizer 106 through the reformed water supply line 114 by the operation of the reformed water pump 113. The raw fuel supply path 112 merges with the reformed water supply path 114 at a portion downstream of the desulfurizer 101, and supplies the reformed water and the raw fuel merged outside the vessel 200 to the vaporizer 106.

The reforming water is vaporized by the vaporizer 106 to form steam. The raw fuel containing steam generated by the vaporizer 106 is supplied to the reformer 102 through a raw fuel supply path 115 containing steam. The raw fuel is steam-reformed by the reformer 102 to generate a reformed gas (first gas having a reducing component) containing hydrogen as a main component. The reformed gas generated by the reformer 102 is supplied to the electrochemical module M through the fuel supply unit 103.

The reaction exhaust gas is combusted in the combustion unit 108 to form combustion exhaust gas, and the combustion exhaust gas is sent from the combustion exhaust gas discharge passage 116 to the heat exchanger 190. In the combustion exhaust gas discharge passage 116, a combustion catalyst section 117 (for example, a platinum catalyst) is disposed to burn and remove reducing components such as carbon monoxide and hydrogen contained in the combustion exhaust gas.

The heat exchanger 190 exchanges heat between the combustion exhaust gas generated by combustion in the combustion unit 108 and the supplied cold water to generate hot water. That is, the heat exchanger 190 operates as an exhaust heat utilization unit that reuses heat discharged from the electrochemical device 100.

Instead of the exhaust heat utilization portion, a reaction exhaust gas utilization portion that utilizes reaction exhaust gas discharged from the electrochemical module M (without being combusted) may be provided. Further, at least a part of the reaction exhaust gas flowing from the first gas discharge portion 62 to the outside of the container 200 may be merged at any portion 100,101,103,106,112,113,115 in fig. 15 and reused. The reaction exhaust gas contains residual hydrogen that is not used for the reaction in the electrochemical element a. In the reaction exhaust gas utilization unit, residual hydrogen gas is utilized to utilize heat by combustion or to generate electricity by a fuel cell or the like, thereby effectively utilizing energy.

[ other embodiments ]

Note that the configurations disclosed in the above embodiments (including other embodiments, the same below) can be combined with the configurations disclosed in the other embodiments without contradiction, and the embodiments disclosed in this specification are exemplary, and the embodiments of the present invention are not limited thereto, and can be appropriately changed without departing from the object scope of the present invention.

(1) In the above embodiment, the turbulence forming body 90 is provided in the internal flow passage a1, and more specifically, the turbulence forming portion 91 is provided in the sub-flow passage a 11. However, turbulence forming bodies 90 may also be provided in flow portion a 2. By providing the turbulence forming body 90 in the flow portion a2, the second gas flowing in the flow portion a2 is set in a turbulent state, and the contact time with the electrode layer 31 can be extended.

Examples of the arrangement of turbulence forming body 90 include a case where turbulence forming body 90 is provided only in sub-flow passage a11, a case where turbulence forming body 90 is provided only in flow portion a2, and a case where turbulence forming body 90 is provided in both sub-flow passage a11 and flow portion a 2.

(2) In the above embodiment, the electrochemical element a is used for a solid oxide fuel cell as the electrochemical device 100, but the electrochemical element a may be used for a solid oxide electrolysis cell, an oxygen sensor using a solid oxide, or the like. The electrochemical element a is not limited to being used in combination as the electrochemical element laminate S or the electrochemical module M, and may be used alone.

That is, in the above embodiment, a configuration capable of improving the efficiency of converting chemical energy such as fuel into electric energy has been described.

That is, in the above embodiment, the electrochemical element a and the electrochemical module M are operated as a fuel cell, and hydrogen gas is flowed through the electrode layer 31 and oxygen gas is flowed through the counter electrode layer 33. Thus, oxygen molecules O in the counter electrode layer 33₂And an electron e^-React to generate oxygen ions O^2-. The oxygen ion O^2-Moves to the electrode layer 31 through the electrolyte layer 32. In the electrode layer 31, hydrogen molecules H₂With oxygen ions O^2-Reacting to form water H₂O and an electron e^-. By the above reaction, an electromotive force is generated between the electrode layer 31 and the counter electrode layer 33, and power is generated.

On the other hand, when the electrochemical element a and the electrochemical module M are operated as an electrolysis unit, a gas containing water vapor and carbon dioxide flows through the electrode layer 31, and a voltage is applied between the electrode layer 31 and the counter electrode layer 33. Thus, electrons e in the electrode layer 31^-With water molecule H₂O, carbon dioxide molecule CO₂React to form hydrogen molecules H₂Carbon monoxide CO and oxygen ion O^2-. Oxygen ion O^2-Moves to the counter electrode layer 33 through the electrolyte layer 32. Oxygen ion O in counter electrode layer 33^2-Release electrons to form oxygen molecules O₂. By the above reaction, water molecule H₂Electrolysis of O to hydrogen H₂And oxygen O₂In the flow of carbon dioxide molecules CO₂In the case of the gas of (3), electrolysis into carbon monoxide CO and oxygen O₂。

The circulating fluid contains water vapor and carbon dioxide molecules CO₂In the case of the gas of (3), a fuel converter 25 (fig. 20) may be provided for synthesizing various compounds such as hydrocarbons from hydrogen gas, carbon monoxide and the like generated in the electrochemical element a and the electrochemical module M by the above-described electrolysis. By means of a fuel supply (not shown),the hydrocarbons and the like generated by the fuel converter 25 can be extracted to the outside of the present system and apparatus and used as fuels for other applications. Further, the hydrogen gas and the carbon monoxide may be converted into chemical raw materials by the fuel converter 25 and utilized.

Fig. 20 shows an example of an energy system Z and an electrochemical device 100 in which the electrochemical reaction unit 3 is operated as an electrolysis unit. The water and carbon dioxide supplied in this system are electrolyzed in the electrochemical reaction section 3 to generate hydrogen, carbon monoxide, and the like. Further, hydrocarbons and the like are synthesized in the fuel converter 25. The energy efficiency can be improved by the above configuration in which the heat exchanger 24 in fig. 20 is operated as an exhaust heat utilization unit for exchanging heat between the reaction heat generated by the reaction in the fuel converter 25 and water and vaporizing the reaction heat, and the heat exchanger 23 in fig. 20 is operated as an exhaust heat utilization unit for exchanging heat between the exhaust heat generated by the electrochemical element a and steam and carbon dioxide and preheating the exhaust heat.

The power converter 93 also supplies electric power to the electrochemical element a. Thereby, the electrochemical element a functions as an electrolysis cell as described above.

Therefore, according to the above configuration, it is possible to provide the electrochemical device 100, the energy system Z, and the like, which can improve the efficiency of converting electric energy into chemical energy such as fuel.

(3) In the above embodiment, NiO, for example, is used as the material of the electrode layer 31_-GDC、Ni_-GDC、NiO_-YSZ、Ni_-YSZ、CuO_-CeO₂、Cu_-CeO₂And the like, and as the material of the counter electrode layer 33, for example, a composite oxide such as LSCF, LSM, and the like is used. In the electrochemical element a configured as described above, hydrogen gas is supplied to the electrode layer 31 to serve as a fuel electrode (anode), and air is supplied to the counter electrode layer 33 to serve as an air electrode (cathode), and thus the electrochemical element a can be used as a solid oxide fuel cell. The electrochemical element a may be configured such that the electrode layer 31 can be an air electrode and the counter electrode layer 33 can be a fuel electrode, with this configuration being modified. That is, as the material of the electrode layer 31, for example, a composite oxide such as LSCF or LSM is used, and as the counter electrode layer 33For example, NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO, etc. are used as the material₂、Cu-CeO₂And the like. In the electrochemical element a having such a configuration, air is supplied to the electrode layer 31 to serve as an air electrode, and hydrogen is supplied to the counter electrode layer 33 to serve as a fuel electrode, so that the electrochemical element a can be used as a solid oxide fuel cell.

(4) In the above embodiment, the electrode layer 31 is provided between the first plate-like member 1 and the electrolyte layer 32, and the counter electrode layer 33 is disposed on the side opposite to the first plate-like member 1 as viewed from the electrolyte layer 32. The electrode layer 31 may be arranged opposite to the counter electrode layer 33. That is, the counter electrode layer 33 may be disposed between the first plate-like member 1 and the electrolyte layer 32, and the electrode layer 31 may be disposed on the side opposite to the first plate-like member 1 as viewed from the electrolyte layer 32. In this case, the supply of gas to the electrochemical element a also needs to be changed.

That is, the order of the electrode layer 31 and the counter electrode layer 33, and whether or not either of the first gas and the second gas is one or the other of the reducing component gas and the oxidizing component gas can be provided in such a manner that the first gas and the second gas react appropriately in the electrode layer 31 and the counter electrode layer 33, and various forms can be adopted.

(5) In the above embodiment, the electrochemical reaction section 3 is provided on the side of the first plate-like body 1 opposite to the second plate-like body 2 so as to cover the gas flow-allowing section 1A, but may be provided on the side of the first plate-like body 1 opposite to the second plate-like body 2. That is, the present invention is also applicable to a configuration in which the electrochemical reaction section 3 is disposed in the internal flow path a 1.

(6) In the above embodiment, the first penetrating portion 41 and the second penetrating portion 51 are provided in a pair at both ends of the rectangular plate-like support, but the present invention is not limited to the form provided at both ends, and 2 or more pairs may be provided. The first penetrating portion 41 and the second penetrating portion 51 need not be provided in pairs. Therefore, 1 or more first penetration portions 41 and second penetration portions 51 may be provided.

Further, the plate-like support is not limited to a rectangular shape, and various shapes such as a square shape and a circular shape may be adopted.

(7) In the above, the electrochemical module M is provided with a functional layer such as an insulating insulator 210. The electrochemical module M may be provided with further functional layers in addition to or instead of the functional layers shown above.

(8) In the above, the lower cover 203 and the upper cover 201 are joined by welding. However, the joining of the lower cover 203 and the upper cover 201 is not limited to welding, and may be joined by, for example, bolts or the like.

(9) Further, in the above, the opening 201c is formed in the upper cover 201, and the opening 203c is formed in the lower cover 203. However, the opening 201c and the opening 203c may not be formed. However, openings through which the first gas supply portion 61 and the first gas discharge portion 62 can communicate with the outside are formed in the upper cover 201. Since the opening 201c and the opening 203c are not provided, the electrochemical element stack S is configured to flow the first gas to the electrochemical element stack S through the first gas supply unit 61 and the first gas discharge unit 62 and to flow the second gas to the electrochemical element stack S through the second gas supply unit 71 and the second gas discharge unit 72, while being accommodated in the container 200 including the upper cover 201 and the lower cover 203.

In this case, a supply protrusion that communicates with the first gas supply portion 61 and protrudes from the upper cover 201 may be formed. Similarly, a discharge protrusion may be formed to communicate with the first gas discharge portion 62 and protrude from the upper cover 201.

(10) In the above, the electrochemical element laminate S is held by the container (first holder and second holder) 200. However, the container 200 is not necessarily used as long as the electrochemical element stack S can be sandwiched. For example, the electrochemical element laminate S may be sandwiched by end plates (first and second sandwiching members) or the like.

(11) The first and second annular seal portions 42 and 52 may have any shape as long as they are configured to prevent gas leakage by allowing the first and second penetrating portions 41 and 51 to communicate with each other. That is, the first and second annular seal portions 42 and 52 may be configured to seal the adjacent electrochemical elements a with each other by an endless configuration having an opening portion communicating with the penetration portion inside. The first and second annular seal portions 42,52 are, for example, annular. The ring shape may be any shape such as a circle, an ellipse, a square, or a polygon.

(12) In the above, the plate-like support 10 is composed of the first plate-like body 1 and the second plate-like body 2. Here, the first plate-like member 1 and the second plate-like member 2 may be formed of different plate-like members, or may be formed of one plate-like member as shown in fig. 19. In the case of fig. 19, the first plate-like member 1 is overlapped with the second plate-like member 2 by bending one plate-like member. The first plate-like body 1 and the second plate-like body 2 are integrated by welding or the like of the peripheral edge portion 1 a. The first plate-like member 1 and the second plate-like member 2 may be formed of a series of seamless plate-like members, or may be formed by bending a series of plate-like members as shown in fig. 19.

As will be described later, the second plate-like body 2 may be formed of one member, or may be formed of 2 or more members. Similarly, the first plate-like body 1 may be constituted by one member, or may be constituted by 2 or more members.

(13) The second plate-like body 2 forms an internal flow passage a1 together with the first plate-like body 1. The internal flow path a1 includes a distribution portion a12, a plurality of sub-flow paths a11, and a junction a 13. As shown in fig. 5, the first gas supplied to the distribution portion a12 is distributed and supplied to each of the sub-passages a11, and merges at the merging portion a13 at the outlet of the sub-passages a 11. Therefore, the first gas flows from the distribution portion a12 in the gas flow direction toward the joining portion a 13.

The plurality of sub-flow paths a11 are formed by forming the portions of the second plate-like body 2 other than the joining portion a13 from the distribution portion a12 into a corrugated plate shape. As shown in fig. 9, the plurality of sub-passages a11 are formed in a wave plate shape in a cross-sectional view in a flow intersecting direction intersecting the gas flow direction of the first gas. The plurality of sub-channels a11 are formed by the wave plates extending in the gas flow direction shown in fig. 5. The plurality of sub-flow paths a11 may be formed of a series of corrugated plate bodies between the distribution portion a12 and the junction a13, or may be formed of 2 or more corrugated plate bodies. The plurality of sub-channels a11 may be formed of, for example, 2 or more corrugated plate-like bodies separated in the direction along the gas flow direction, or 2 or more corrugated plate-like bodies separated in the direction along the cross flow direction.

As shown in fig. 9, the plurality of sub-passages a11 are formed in a wave shape by repeating the formation of peaks and valleys having the same shape. However, the second plate-like body 2 may also have a plate-like portion in a region where the plurality of sub flow paths a11 are formed. For example, the plurality of sub flow paths a11 may be formed by alternately forming plate-like portions and protrusion-like portions. The projection may be a portion through which a fluid such as a first gas flows.

(14) The second plate-like member 2 does not need to be formed in a corrugated plate shape over the entire surface thereof corresponding to the plurality of sub-channels a11, and at least a part thereof may be formed in a corrugated plate shape. For example, the second plate-like body 2 may have a flat plate shape in a part of the gas flow direction and a corrugated plate shape in the remaining part between the distribution part a12 and the junction part a 13. Further, the second plate-like body 2 may have a flat plate shape in a part in the cross flow direction and a corrugated plate shape in the remaining part.

(15) The internal flow path a1 may be provided with a structure that can improve power generation efficiency. Such a structure will be described below. The description overlapping with the above embodiment is simplified or omitted.

(I) Specific constitution of electrochemical Module M

Next, a specific configuration of the electrochemical module M will be described with reference to fig. 21 to 38. The electrochemical module M includes the electrochemical element stack S shown in fig. 4.

Here, as shown in fig. 21 to 38, etc., the stacking direction of the electrochemical element stack S is the + Z direction and the-Z direction (Z direction). Further, the direction in which the first gas flows from the first gas supply portion 61 side to the first gas discharge portion 62 side between the first plate-like member 1 and the second plate-like member 2, and the direction in which the second gas flows from the second gas supply portion 71 side to the second gas discharge portion 72 side between the first plate-like member 1 and the second plate-like member 2 are the + X direction and the-X direction (X direction) intersecting the + Z direction and the-Z direction (Z direction). Further, directions intersecting the + Z direction and the-Z direction (Z direction) and the + X direction and the-X direction (X direction) are the + Y direction and the-Y direction (Y direction). The XZ plane, the XY plane, and the YZ plane are substantially perpendicular to each other.

As shown in fig. 4, 21, and the like, the electrochemical module M includes: a first gas supply unit 61 that supplies a first gas to the internal flow path a1 via the supply path 4; a first gas discharge part 62 that discharges the first gas after the reaction; a second gas supply unit 71 for supplying a second gas to the flow unit a2 from the outside; a second gas discharge portion 72 that discharges the second gas after the reaction; and an output unit 8 for obtaining an output associated with the electrochemical reaction in the electrochemical reaction unit 3; the container 200 includes a distribution chamber 9 for distributing and supplying the second gas supplied from the second gas supply unit 71 to the flow portion a 2.

As a result, the electrochemical module M is supplied with the fuel gas (also referred to as a first gas) from the first gas supply unit 61 and with the air (also referred to as a second gas) from the second gas supply unit 71, so that the fuel gas enters as indicated by the broken line arrows in fig. 4 and 22, and the air enters as indicated by the solid line arrows.

The fuel gas supplied from the first gas supply portion 61 is guided from the first penetration portion 41 of the uppermost electrochemical element a of the electrochemical element stack S to the supply passage 4, and flows from the supply passage 4 partitioned by the first annular seal portion 42 to the internal flow passages a1 of all the electrochemical elements a. The air supplied from the second gas supply portion 71 flows into the distribution chamber 9 once and then flows into the flow portion a2 formed between the electrochemical elements a. In the present embodiment, the flow direction of the fuel gas flowing along the plane of the plate-like support 10 in the internal flow path a1 is a direction from the + X direction toward the-X direction. Similarly, the flow direction of the air flowing along the plane of the plate-like support 10 in the flow portion a2 is a direction from the + X direction toward the-X direction.

Then, if the second plate-like member 2 (a part of the plate-like support 10) is used as a reference, the portion of the second plate-like member 2 that has a wave-plate shape and protrudes from the first plate-like member 1 (a part of the plate-like support 10) can be electrically connected by contacting the electrochemical reaction parts 3 of the adjacent electrochemical elements a while forming the internal flow path a1 between the first plate-like member 1 and the second plate-like member 2. On the other hand, the portion of the corrugated plate-shaped second plate-shaped body 2 in contact with the first plate-shaped body 1 is electrically connected to the first plate-shaped body 1, and the flow portion a2 is formed between the electrochemical reaction portion 3 of the electrochemical element a adjacent to the second plate-shaped body 2.

In some of fig. 37 and the like, there are electrochemical elements a in which a cross section including the internal flow path a1 appears and electrochemical elements a in which a cross section including the flow portion a2 appears are shown in parallel for convenience, but the fuel gas supplied from the first gas supply portion 61 reaches the distribution portion a12 (see fig. 21 to 24 and the like), flows while widening in the width direction of one end portion side through the distribution portion a12, and reaches each sub-flow path a11 (see fig. 21 to 24 and the like) in the internal flow path a 1.

Here, as shown in fig. 21 and the like, the internal flow path a1 includes a distribution portion a12, a plurality of sub flow paths a11, and a merging portion a13 described later. The internal flow path a1 includes a supply buffer section 144 between the distribution section a12 and the plurality of sub-flow paths a11, and a discharge buffer section 154 between the plurality of sub-flow paths a11 and the junction a 13.

The internal flow passage a1 is formed by a space where the first plate-like member 1 and the second plate-like member 2 face each other. In the present embodiment, the first plate-like body 1 is flat and forms a gas flow allowing portion 1A described later. The second plate-like body 2 has a portion protruding upward in the stacking direction and a portion recessed downward. Therefore, by combining the first plate-like member 1 and the second plate-like member 2 to face each other, the portion of the second plate-like member 2 protruding upward comes into contact with the first plate-like member 1. Further, the downwardly recessed portion of the second plate-like body 2 and the first plate-like body 1 form a space that separates the distribution portion a12, the supply buffer portion 144, the plurality of sub flow paths a11, the discharge buffer portion 154, and the merging portion a 13.

As described later in detail, the supply structure 140 is provided between the distribution portion a12 and the plurality of sub-flow paths a11 in the direction (+ X direction and-X direction (X direction)) along the flow direction of the fuel gas. The supply structure 140 temporarily stores the fuel gas in the distribution portion a12, and restricts the supply of the fuel gas from the distribution portion a12 to the plurality of sub-channels a 11.

Further, the vent structure 150 is provided between the plurality of sub-passages a11 and the joining portion a13 in a direction along the flow direction of the fuel gas. The discharge structure 150 restricts the discharge of the fuel gas from the plurality of sub-channels a11 to the joining portion a 13.

The fuel gas flows through the first gas supply portion 61, the first annular seal portion 42, the first penetration portion 41, and the like, and is supplied to the distribution portion a12 of each electrochemical element a. The fuel gas supplied to distribution portion a12 is temporarily stored in distribution portion a12 by supply structure 140. Thereafter, the fuel gas is introduced from the distribution portion a12 into the plurality of sub flow paths a 11.

The fuel gas introduced into each of the sub-passages a11 flows through each of the sub-passages a11, and enters the electrode layer 31 and the electrolyte layer 32 through the gas flow-allowing portion 1A. The fuel gas further flows through the sub-flow path a11 together with the fuel gas that has completed the electrochemical reaction. The fuel gas that has reached the end of the plurality of sub-channels a11 in the flow direction advances to the junction a13 while being partially restricted from flowing to the junction a13 by the vent structure 150. The fuel gas that has advanced to the joining portion a13 flows through the joining portion a13, the second penetration portion 51, the second annular seal portion 52, and the like. And, together with the fuel gas from the other electrochemical element a, which finishes the electrochemical reaction, is discharged from the first gas discharge portion 62 to the outside.

On the other hand, the air supplied from the second gas supply unit 71 can enter the flow portion a2 through the distribution chamber 9, and can enter the counter electrode layer 33 and the electrolyte layer 32. Further, the air further advances in the flow portion a2 along the electrochemical reaction portion 3 together with the air having finished the electrochemical reaction, and is discharged from the second gas discharge portion 72 to the outside.

In accordance with the flow of the fuel gas and the air, the electric power generated in the electrochemical reaction section 3 is connected in series between the current collectors 81 and 82 by the contact between the electrochemical reaction section 3 of the adjacent electrochemical element a and the second plate-like body 2, and the synthesized output is extracted from the output section 8.

The structure of the electrochemical element laminate S will be described in detail later.

(II) constitution of internal channel and second plate-like body

The configuration of the internal flow path a1 formed by the first plate-like member 1 and the second plate-like member 2 facing each other will be described further.

In the present embodiment, the first plate-like body 1 having a flat plate shape and the second plate-like body 2 formed to have an uneven shape so as to protrude upward (+ Z direction) in the stacking direction or so as to be recessed downward (-Z direction) in the stacking direction are opposed to each other, and the inner surface obtained by combining them is formed with the inner flow path a 1. The internal flow path a1 includes a distribution portion a12, a supply buffer portion 144, a plurality of sub flow paths a11, a discharge buffer portion 154, and a junction portion a 13. The internal flow path a1 also includes a supply passage portion 141 (a part of the supply structure 140) through which the first gas passes and a discharge passage portion 151 (a part of the discharge structure 150).

The supply path 4 side where the first gas supply portion 61, the first annular seal portion 42, the first penetration portion 41, and the like are provided, and the discharge path 5 side where the first gas discharge portion 62, the second annular seal portion 52, the second penetration portion 51, and the like are provided are symmetrical. Fig. 22 to 24, 26 to 29, and the like show cross-sectional views of the discharge path 5 side where the first gas discharge portion 62, the second annular seal portion 52, the second penetration portion 51, and the like are provided. On the other hand, fig. 30 to 36 and the like show cross-sectional views of the supply passage 4 side where the first gas supply portion 61, the first annular seal portion 42, the first penetration portion 41 and the like are provided. In the cross-sectional views on the side of the discharge path 5 such as fig. 22 to 24 and fig. 26 to 29, the first gas flows in the direction of being discharged from the plurality of sub-flow paths a11 to the second penetration portion 51 and the like through the junction a 13. On the other hand, in the cross-sectional view on the supply passage 4 side such as fig. 30 to 36, the first gas flows in the direction of supply from the distribution portion a12 to the plurality of sub-passages a11 through the first penetration portion 41 and the like.

The distribution portion a12 is provided corresponding to each electrochemical element a. The distribution portion a12 is a buffer portion provided on the supply path 4 side and configured to supply the first gas to each electrochemical element a. The distribution portion a12 is provided on the upstream side of the plurality of sub-passages a11 in the internal passage a1 in the flow direction of the first gas (the direction from the + X direction toward the-X direction). As shown in fig. 21, 38, and the like, the distribution portion a12 has a first penetration portion 41 formed to penetrate the second plate-like body 2 at substantially the center of the direction (+ Y direction and-Y direction (Y direction)) intersecting the flow direction and the flow direction (+ X direction and-X direction (X direction)). The first gas flows through the first gas supply portion 61, the first annular seal portion 42, the first penetration portion 41, and the like, and is supplied to the distribution portion a12 of each electrochemical element a.

As shown in fig. 22 to 36, the first plate-like member 1 and the second plate-like member 2 are integrated by welding the edge portion of the first plate-like member 1 and the edge portion of the second plate-like member 2 to the peripheral edge portion 1 a. The distribution portion a12 is formed by processing the second plate-like body 2 so as to be recessed below the peripheral edge portion 1a in the stacking direction (-Z direction). Further, the distribution portion a12 is formed so as to be located at a different position in the stacking direction from the supply blocking portion 142 (a part of the supply structure 140). That is, as shown in fig. 33 and the like, the upper surface of the dispensing portion a12 is located below the upper surface of the supply blocking portion 142 in the stacking direction. The upper surface of the supply blocking portion 142 abuts against the lower surface of the first plate-like member 1. Thus, the first gas introduced into the dispenser a12 is restricted from being discharged from the dispenser a12 by the supply blocking portion 142 protruding upward in the stacking direction, and is temporarily stored in the dispenser a12 formed in a concave shape.

Further, the dispensing portion a12 is long in the + Y direction and the-Y direction (Y direction) as shown in fig. 21 and the like in a top view. The Y-direction length of the distribution portion a12 corresponds to the Y-direction length of the region of the plurality of sub flow paths a11 arranged in parallel at intervals in the Y-direction.

As shown in fig. 21 to 38, the plurality of sub-passages a11 through which the first gas flows extend in the flow direction, i.e., in the + X direction and the-X direction (X direction). As described above, the plurality of sub-channels a11 are arranged in parallel at intervals in the Y direction. As shown in fig. 21 to 38, the second plate-like member 2 includes a plurality of sub-passage forming portions 160 forming a plurality of sub-passages a11, and a plurality of partition portions 161 provided between adjacent sub-passage forming portions 160 and partitioning adjacent sub-passages a 11. As shown in fig. 37 and the like, the secondary flow path forming portion 160 is formed into a concave shape having a bottom surface, and the upper surface of the partition portion 161 is located above the bottom surface of the secondary flow path forming portion 160 in the stacking direction. The upper surface of the partition 161 abuts against the lower surface of the first plate-like body 1. Thereby, the sub-passages a11 are separated, and the first gas flows through the sub-passages a11 in the flow direction.

In fig. 21 and the like, the sub-flow path a11 extends in the flow direction from the vicinity of the supply structure 140 to the vicinity of the discharge structure 150. However, the sub-flow path a11 is not limited to this, and may be formed only in a part from the vicinity of the supply structure 140 to the vicinity of the discharge structure 150. That is, the sub-flow path forming portion 160 forming the sub-flow path a11 may be disposed only in a part from the vicinity of the supply structure 140 to the vicinity of the discharge structure 150.

As shown in fig. 37 and 38, the length L3 of the partition 161 is smaller than the length L4 of the sub-channel forming portion 160 in the + Y direction and the-Y direction (Y direction, intersecting direction with the flow direction) (L3 < L4). In the case of L3 < L4, as shown in fig. 37 and the like, the contact area between the upper surface of the partition 161 and the lower surface of the first plate-like body 1 can be reduced. That is, the space of the secondary flow path a11 facing the first plate-like body 1 forming the gas flow permission portion 1A can be increased, and the amount of the first gas flowing from the secondary flow path a11 to the electrochemical reaction portion 3 can be increased.

As shown in fig. 21, 30 to 38, and the like, the second plate-like body 2 has the supply structures 140 between the distribution portion a12 and the plurality of sub-channels a11 in the direction (+ X direction and-X direction (X direction)) along the flow direction. The supply structure 140 temporarily stores the first gas in the distribution portion a12, and restricts the supply of the first gas from the distribution portion a12 to the plurality of sub-passages a 11.

The supply structure 140 includes a plurality of supply passage portions 141 and a plurality of supply blocking portions 142. The supply passage section 141 allows the first gas to pass from the distribution section a12 to the plurality of sub flow paths a 11. The supply blocking unit 142 blocks the first gas from passing from the distribution unit a12 to the plurality of sub flow paths a 11. As shown in fig. 32 and the like, the upper surface of the supply blocking portion 142 is positioned above the upper surface of the supply passage portion 141 in the stacking direction and abuts against the lower surface of the first plate-like body 1. Therefore, the first gas in the distributor a12 is blocked from flowing in the flow direction by the supply blocking unit 142, and flows in the flow direction through the supply passing unit 141 and flows into the plurality of sub flow paths a 11.

In the present embodiment, each supply blocking portion 142 is formed in a substantially rectangular shape as shown in fig. 21, 38, and the like, for example. The rectangular supply blocking portions 142 are arranged along the Y direction such that the long sides thereof extend along the + Y direction and the-Y direction (Y direction). The supply passage portion 141 is provided between the adjacent supply blocking portions 142. That is, the supply passage portion 141 is provided in a section in which the short sides of the adjacent supply blocking portions 142 face each other.

As shown in fig. 38, the length L2 of the supply blocking portion 142 is greater than the length L1 of the supply passage portion 141 in the + Y direction and the-Y direction (Y direction, intersecting direction with the flow direction) (L2 > L1). Further, the length L1 of the supply passage portion 141 is preferably smaller than the length L3 of the partition 161 (L1 < L3). This allows the first gas pushed out from the distribution portion a12 through the supply passage portion 141 to collide with the end portion of the partition 161 on the + X direction side, and to be temporarily stored in the supply buffer portion 144 described later.

The relationship between L1 and L2 is determined by, for example, the amount of the first gas to be supplied to the distribution portion a12 per unit time, the amount of the first gas to be supplied to the plurality of sub flow paths a11 per unit time, the number of supply blocking portions 142, the length L3 of the partition 161 in the Y direction, the length L4 of the sub flow path a11 in the Y direction, and the like.

As described above, the sub-passages a11 are partitioned by the partitions 161. In the flow direction (+ X direction and-X direction (X direction)), any one of the plurality of partitions 161 is disposed to correspond to the supply passage portion 141.

In the flow direction, at least 1 of the sub-flow passages a11 among the plurality of sub-flow passages a11 is disposed to correspond to the supply blocking portion 142.

Here, the first gas is introduced from the distribution portion a12 into the plurality of sub-passages a11 through the supply passage portion 141. According to the above configuration, since any of the partition portions 161 is disposed in the flow direction so as to correspond to the supply passage portion 141, the first gas pushed out from the distribution portion a12 to the supply passage portion 141 advances in the flow direction and collides with the partition portion 161 protruding upward in the stacking direction. By the collision with the partition 161, the first gas advances in the intersecting direction intersecting the flow direction. That is, the first gas flowing from the distribution portion a12 through the supply passage portion 141 is not immediately introduced into the plurality of sub-passages a11, but flows forward in the intersecting direction while colliding with the partition 161 in front of the sub-passage a 11. Further, the first gas advancing in the cross direction is temporarily stored between the supply structure 140 and the plurality of sub flow paths a11 without returning to the distribution portion a12 by the supply blocking portion 142 protruding upward in the stacking direction. Thereafter, the first gas is introduced into the plurality of sub flow paths a11 formed by the plurality of sub flow path forming portions 160 along with the extrusion from the distribution portion a 12.

The region where the first gas is temporarily stored between the supply structure 140 and the plurality of sub-channels a11 is the supply buffer 144.

In the present embodiment, 1 partition 161 is disposed corresponding to 1 supply passage 141 in the flow direction. However, the present invention is not limited to this, and a plurality of partition portions 161 may be arranged corresponding to 1 supply passage portion 141. Note that the partition 161 may be disposed not corresponding to 1 supply passage 141, but corresponding to another supply passage 141.

Further, the supply blocking portion 142 is provided corresponding to the first penetration portion 41 in the flow direction. This can suppress the first gas introduced from the first penetration portion 41 into the distribution portion a12 from immediately flowing to the plurality of sub flow paths a 11. Therefore, the first gas can be temporarily stored in the distribution portion a 12.

The number of supply preventing portions 142 is not limited to this, but is, for example, 2 or more. It is preferable that the number of the supply blocking portions 142 be set according to the number of the plurality of sub flow paths a 11.

The supply blocking portions 142 are arranged in a row in the direction intersecting the flow direction. However, the arrangement is not limited to this as long as the first gas is temporarily stored in the distribution portion a12 and can be supplied substantially uniformly to the plurality of sub-passages a 11. For example, the plurality of supply blocking portions 142 may be arranged offset from the intersecting direction. The plurality of supply blocking portions 142 may be arranged along the intersecting direction or offset from the intersecting direction.

In the above, the supply blocking unit 142 has a rectangular shape. However, the shape of the supply blocking portion 142 is not limited to this as long as the gas can be uniformly supplied from the distribution portion a12 to the plurality of sub flow paths a 11. For example, the supply blocking part 142 may be formed in various shapes such as a square, a circle, an ellipse, and a triangle.

Further, as shown in the above-described embodiments such as fig. 21 and 38, it is preferable that 2 of the plurality of supply blocking portions 142 are provided at positions corresponding to the + Y direction end and the-Y direction end of the dispenser a12, respectively. The first gas spreads over the distribution portion a12 so as to widen the space in the distribution portion a12 from the first penetration portion 41 of the distribution portion a12, and collides with the end face of the distribution portion a 12. Therefore, the first gas that collides with the end surface of the distribution portion a12 may change its direction at the end surface and flow toward the plurality of sub flow paths a 11. Therefore, by providing the supply blocking portion 142 in advance at a position corresponding to the end of the distribution portion a12, the first gas can be inhibited from immediately flowing out from the distribution portion a12 to the plurality of sub flow paths a 11. As a result, as will be described later, the first gas can be supplied from the distribution portion a12 to each of the sub flow paths a11 substantially uniformly.

Next, the junction a13 and the discharge structure 150 will be described. The merging section a13 and the discharge structure 150 each have the same configuration as the distribution section a12 and the supply structure 140.

The merging portion a13 is a buffer portion provided on the discharge path 5 side for discharging the first gas flowing through the plurality of sub-paths a 11. The merging portion a13 is provided downstream of the plurality of sub flow paths a11 in the internal flow path a1 in the flow direction of the first gas. As shown in fig. 21, 38, and the like, the joining portion a13 has a second penetrating portion 51 penetrating the second plate-like body 2 at a substantially central portion in the flow direction and the intersecting direction thereof. The first gas passing through the plurality of sub-flow paths a11 is introduced into the joining portion a13 and discharged to the outside through the second penetration portion 51, the second annular seal portion 52, the first gas discharge portion 62, and the like.

The merging portion a13 is formed so as to be positioned differently in the stacking direction in the discharge preventing portion 152 (a part of the discharge structure 150). That is, as shown in fig. 26 and the like, the upper surface of the merging portion a13 is located below the upper surface of the discharge preventing portion 152 in the stacking direction. The upper surface of the discharge preventing portion 152 abuts against the lower surface of the first plate-like body 1. Thus, the first gas flowing from the plurality of sub-channels a11 toward the junction a13 is restricted from being discharged to the junction a13 by the discharge preventing portion 152 protruding upward in the stacking direction, and temporarily stays in the plurality of sub-channels a 11.

Further, the joining portion a13 is long in the + Y direction and the-Y direction (Y direction) as shown in fig. 21 and the like in a top view. The Y-direction length of the junction a13 corresponds to the Y-direction length of the region of the plurality of sub flow paths a11 arranged in parallel at intervals in the Y-direction.

As shown in fig. 21, 25 to 29, 38, and the like, the second plate-like body 2 has the vent structure 150 between the plurality of sub-flow paths a11 and the junction a13 in the direction (+ X direction and-X direction (X direction)) along the flow direction. The discharge structure 150 restricts discharge of the first gas from the plurality of sub-channels a11 to the joining portion a 13.

The discharge structure 150 has a plurality of discharge passing portions 151 and a plurality of discharge blocking portions 152. The discharge passage section 151 passes the first gas from the plurality of sub-flow paths a11 to the joining section a 13. The discharge preventing portion 152 prevents the first gas from passing from the plurality of sub flow paths a11 to the merging portion a 13. As shown in fig. 26 and the like, the upper surface of the discharge preventing portion 152 is positioned above the upper surface of the discharge passing portion 151 in the stacking direction and abuts against the lower surface of the first plate-like body 1. Therefore, the first gas in the plurality of sub-passages a11 is blocked from flowing in the flow direction by the discharge blocking section 152, flows in the flow direction through the discharge passage section 151, and flows into the junction section a 13.

In the present embodiment, the discharge preventing portion 152 is formed in a substantially rectangular shape as shown in fig. 21, 38, and the like, for example, similarly to the supply preventing portion 142. The rectangular discharge preventing portions 152 are arranged along the Y direction such that the long sides thereof extend along the + Y direction and the-Y direction (Y direction). The discharge passing part 151 is provided between the adjacent discharge blocking parts 152. That is, the discharge passing portion 151 is disposed in a section where the short sides of the adjacent discharge preventing portions 152 are opposed.

As shown in fig. 38, the length L12 of the discharge inhibiting portion 152 is greater than the length L11 of the discharge passing portion 151 in the + Y direction and the-Y direction (Y direction, intersecting direction with the flow-through direction) (L12 > L11). Further, the length L12 of the discharge preventing portion 152 is preferably greater than the length L4 of the sub flow path forming portion 160 (L12 > L3). This makes it possible to cause the first gas flowing from the plurality of sub-flow paths a11 toward the junction a13 to collide with the emission preventing section 152, and to temporarily store the first gas in the emission buffer section 154 to be described later,

The relationship between L11 and L12 is determined by, for example, the amount of the first gas supplied to the plurality of sub flow paths a11 per unit time, the amount of the first gas to be discharged from the junction a13 per unit time, the number of the discharge stoppers 152, the length L3 of the partition 161 in the Y direction, the length L4 of the sub flow path a11 in the Y direction, and the like.

In the flow direction, at least 1 of the sub-flow passages a11 among the plurality of sub-flow passages a11 is disposed corresponding to the discharge blocking portion 152.

Further, in the flow direction, any one of the plurality of partitions 161 is disposed corresponding to the discharge passage 151.

According to the above configuration, the first gas pushed out from the plurality of sub-passages a11 collides with the discharge preventing portion 152 protruding upward in the stacking direction as it advances in the flow direction. By the collision with the discharge preventing portion 152, the first gas advances in the intersecting direction intersecting the flow direction. That is, the first gas flowing from the plurality of sub-flow paths a11 does not immediately flow into the merging portion a13, but rather, collides with the discharge preventing portion 152 before the merging portion a13 and advances in the intersecting direction. Thereafter, the first gas is introduced into the joining portion a13 through the discharge passage portion 151 along the extrusion from the plurality of sub flow paths a 11.

Note that, a region where the first gas is temporarily stored between the plurality of sub-passages a11 and the discharge structure 150 is the discharge buffer section 154.

Further, in the flow direction, the discharge blocking portion 152 is provided corresponding to the second penetration portion 51. This can suppress the first gas flowing through the plurality of sub-flow paths a11 from being immediately introduced into the junction a13 and discharged from the second penetration portion 51. Therefore, the first gas can be temporarily stored in the plurality of sub-passages a 11.

The discharge passage portion 151 and the discharge preventing portion 152 have the same shape, size, arrangement, number, etc. as the supply passage portion 141 and the supply preventing portion 142. For example, in fig. 38, the length L12 of the discharge preventing portion 152 and the length L11 of the discharge passing portion 151 in the + Y direction and the-Y direction (Y direction, a crossing direction crossing the flow direction) are the same as the length L1 of the supply preventing portion 142 and the length L2 of the supply passing portion 141.

However, the shapes, sizes, arrangements, numbers, etc. of the discharge passing portion 151 and the discharge blocking portion 152 may be different from those of the supply passing portion 141 and the supply blocking portion 142. For example, the size of the discharge passage 151 may be larger than the supply passage 141. Accordingly, the discharge pressure from the plurality of sub-passages a11 to the joining portion a13 may be set lower than the supply pressure when the first gas is supplied from the distribution portion a12 to the plurality of sub-passages a 11. The first gas can be supplied from the distribution portion a12 to the plurality of sub-passages a11 at a certain supply pressure, the flow distribution between the plurality of sub-passages a11 can be made constant, and the first gas can be smoothly introduced into the merging portion a13 when discharged.

(a) Effects of supply structure and discharge structure

(a1) Function of supply structure

Next, the operation of the supply structure 140 will be described.

The supply blocking unit 142 of the supply structure 140 configured as described above is provided between the distribution unit a12 and the plurality of sub flow paths a11, and forms a barrier for the first gas flowing from the distribution unit a12 to the plurality of sub flow paths a 11. Therefore, the pressure loss of the first gas when the first gas flows from the distribution portion a12 to the plurality of sub flow paths a11 becomes high, and the first gas introduced into the distribution portion a12 is diffused so as to fill the distribution portion a12 and temporarily stored. Therefore, the pressure in the entire distribution portion a12 becomes substantially uniform (pressure equalization). That is, the differential pressure between the distribution portion a12 and each of the plurality of sub flow paths a11 becomes substantially the same. In addition, since the first gas is supplied from the distribution portion a12 to the plurality of sub-flow paths a11 through the supply passage portion 141, the first gas is supplied in a state of being substantially equalized in pressure in each sub-flow path a 11. Thus, the flow distribution (flow velocity, flow rate, pressure, and the like) of the first gas along the flow direction is substantially uniform among the sub-flow paths a 11.

The first gas is divided into a plurality of sub-channels a11 from the distribution portion a12 and flows. By utilizing the rectifying action of dividing the first gas into a plurality of flow paths in this manner, the flow distribution (flow velocity, flow rate, pressure, and the like) of the first gas is substantially constant as compared with the case where the first gas flows through the internal flow path in which the plurality of flow paths are not formed.

As described above, the flow distribution of the first gas along the flow direction is substantially uniform between the sub-flow paths a 11. For example, when a certain position in the flow direction is observed between the sub-passages a11, the flow velocity, flow rate, pressure, and the like of the first gas in the sub-passages a11 are substantially constant in the intersecting direction intersecting the certain position. In this way, in the electrochemical reaction section 3, the difference between the portion where the first gas is insufficient and the portion where the first gas is excessively circulated is reduced, and the utilization rate of the first gas in the entire electrochemical element a is increased, thereby making it possible to improve the reaction efficiency of the electrochemical reaction.

When the distribution portion a12, the plurality of sub passages a11, the supply structure 140, and the like are not used, the flow distribution of the first gas in each sub passage a11 is different, and the flow velocity of the first gas may be high in a certain sub passage a11 and low in another sub passage a 11. The sub-flow path a11 in which the flow rate of the first gas is low consumes the first gas by the electrochemical reaction, and the first gas is insufficient. This reduces the concentration of the first gas, and the electrode layer of the electrochemical reaction section 3 is oxidized and deteriorated, which may reduce the electrode performance and mechanical strength. On the other hand, in the sub-passage a11 in which the flow rate of the first gas is high, the first gas is discharged before being consumed in the electrochemical reaction. That is, when the first gas is a fuel gas such as hydrogen, the first gas having a high concentration is discharged, and the fuel utilization rate is lowered. Here, it is also possible to increase the supply amount of the first gas to each of the sub-passages a11 in consideration of the shortage of the first gas in the sub-passage a11 in which the flow rate of the first gas is slow. However, in this case, in the sub-passage a11 in which the flow rate of the first gas is high, the amount of the first gas discharged before consumption in the electrochemical reaction further increases, and the fuel efficiency further decreases. Accordingly, when the flow distribution of the first gas in each sub-passage a11 is different, the reaction efficiency of the electrochemical reaction is reduced, and the power generation efficiency is reduced.

(a2) Function of the discharge structure

Next, the operation of the discharge structure 150 will be described.

According to the above configuration, not only the supply structure 140 for supplying the first gas from the distribution portion a12 to the plurality of sub flow paths a11 with a substantially uniform flow distribution but also the discharge structure 150 is provided at the portion where the first gas merges at the merging portion a13 from the plurality of sub flow paths a 11. Since the plurality of sub-flow paths a11 are sandwiched between the supply structure 140 and the discharge structure 150, the reaction efficiency of the electrochemical reaction can be improved while the flow distribution (flow velocity, flow rate, pressure, and the like) of the first gas in the plurality of sub-flow paths a11 is substantially uniform.

More specifically, the emission preventing portion 152 of the emission structure 150 configured as described above is provided between the plurality of sub-flow paths a11 and the junction a13, and forms a barrier for the first gas flowing from the sub-flow path a11 to the junction a 13. Therefore, the pressure loss of the first gas when flowing from the plurality of sub-channels a11 to the junction a13 becomes high. Therefore, the first gas introduced into the plurality of sub-passages a11 is difficult to be introduced into the junction a13 from the plurality of sub-passages a11 at once, and spreads so as to fill the plurality of sub-passages a 11. This makes it possible to substantially equalize the flow distribution (flow velocity, flow rate, pressure, and the like) of the first gas along the flow direction among the sub-flow paths a 11. Further, since the first gas is diffused so as to fill the plurality of sub-channels a11, the electrochemical reaction sufficiently proceeds in the plurality of sub-channels a 11. This can improve the reaction efficiency of the electrochemical reaction.

(16) In the above embodiment, the electrochemical device includes the electrochemical module M having the plurality of electrochemical elements a. However, the electrochemical device of the above embodiment can also be applied to a configuration having 1 electrochemical element.

(17) In fig. 1 of the above embodiment, the electrochemical element laminate S is sandwiched between the upper plates 230T via the upper insulator 210T on the upper side in the lamination direction. The electrochemical element stack S is sandwiched between the lower plates 230B via the lower insulators 210B on the lower side in the stacking direction. The electrochemical element stack S, the upper insulator 210T, the upper plate 230T, the lower insulator 210B, and the lower plate 230B arranged in this manner are accommodated in the container 200. The holder in the claims corresponds to the upper and lower plates 230 and the container 200. Alternatively, the holder in the claims may be the upper and lower plates 230, or may be the container 200.

Description of the reference numerals

1: a first plate-shaped body

1A: gas flow-through allowing unit

2: second plate-shaped body

3: electrochemical reaction part

9: distribution chamber

10: plate-shaped support

31: electrode layer

32: electrolyte layer

33: counter electrode layer

41: the first penetrating part

42: a first annular seal part

51: second penetration part

52: second annular seal

90: turbulence forming body

91: turbulence forming part

100: electrochemical device

200: container with a lid

201: upper cover

203: lower cover

210: insulator

230: board

A: electrochemical element

A: first electrochemical element

A: second electrochemical element

A1: internal flow path

A11: secondary flow path

A12: distribution part

A13: confluence part

A2: circulation part

M: electrochemical module

S: electrochemical element laminate

Z: energy system