阅读说明：本技术 异型集电器、pem电解水制氢装置及电解水制氢的方法 (Special-shaped current collector, PEM water electrolysis hydrogen production device and water electrolysis hydrogen production method ) 是由 刘高阳 柳小祥 王新东 杨兆一 王冬冬 杨金梦 毕俊 于 2020-04-28 设计创作，主要内容包括：本发明提供了一种异型集电器、PEM电解水制氢装置及电解水制氢的方法,所述异型集电器包括：第一通道,由多孔基体构成；第二通道,沿多孔基体顶面形成的流道或垂直于多孔基体顶面形成的直穿孔；所述第一通道和第二通道共同形成气液传输通道所述异型集电器为一种具备燃料电池与水电解池流场板与气液扩散层作用的异型集电器器件,能够达到去成本,优化燃料电池与水电解池结构的目的。(The invention provides a special-shaped current collector, a PEM water electrolysis hydrogen production device and a water electrolysis hydrogen production method, wherein the special-shaped current collector comprises the following components: a first channel formed by a porous matrix; a second channel formed along the flow channel or a straight through hole formed perpendicular to the top surface of the porous substrate; the first channel and the second channel jointly form a gas-liquid transmission channel, and the special-shaped current collector is a special-shaped current collector device with the functions of a fuel cell, a water electrolysis cell flow field plate and a gas-liquid diffusion layer, and can achieve the purposes of cost reduction and optimization of structures of the fuel cell and the water electrolysis cell.)

1. A profiled current collector, characterized in that it comprises:

a first channel formed by a porous matrix;

a second channel parallel to the flow channel formed on the top surface of the porous substrate or perpendicular to the straight through hole formed on the top surface of the porous substrate;

the first channel and the second channel jointly form a gas-liquid transmission channel.

2. The profiled current collector defined in claim 1, wherein the porous matrix is formed by sintering composite particles of stainless steel, titanium or titanium alloy of different particle sizes, the sintered porous material having different porosity.

3. The profiled current collector defined in claim 1 wherein the flow channels are comprised of one or more of parallel flow channels, serpentine flow channels, dotted flow channels, interdigitated flow channels and biomimetic flow channels.

4. A profiled current collector according to claim 1 wherein the straight perforated aperture forms include circular, triangular and square.

5. A profiled current collector as claimed in claim 1 wherein the profiled current collector top surface is further provided with a corrosion resistant conductive coating comprising a nitride coating formed by embedded nitriding, sputtered gold and tantalum.

6. A profiled current collector as claimed in claim 1 wherein the second channel is formed by etching, machining and stamping.

7. A PEM electrolytic water hydrogen production device, comprising the special-shaped current collector as claimed in any one of claims 1 to 6, wherein the device comprises a base, an anode special-shaped current collector, a proton exchange membrane module, a cathode special-shaped current collector and a top cover which are connected in sequence, and PTFE gaskets are respectively arranged between the anode special-shaped current collector and the proton exchange membrane module and between the cathode special-shaped current collector and the proton exchange membrane module.

8. The PEM electrolyzed water hydrogen production device of claim 7, further comprising a fastening bolt disposed at one end of the base and a fastening nut disposed at one end of the pressing sheet, wherein the fastening bolt penetrates through the base, the anode profiled current collector, the proton exchange membrane module, the cathode profiled current collector and the top cover and is connected with the fastening nut, and a metal gasket is further disposed at one end of the cathode profiled current collector, which is close to the proton exchange membrane module.

9. The PEM electrolytic water hydrogen production device according to claim 7, which is applied to a PEM water electrolysis cell or a PEM fuel cell.

10. A method for producing hydrogen by electrolyzing water, which is based on the PEM water electrolysis hydrogen production device of any one of claims 7-9, and is characterized in that the method comprises the following steps:

step (1): the pure water directly reaches the anode catalyst layer through the anode special-shaped current collector to generate oxygen;

step (2): oxygen returns to the anode special-shaped current collector and flows out of the water oxygen outlet together with the non-electrolyzed pure water;

and (3): the proton passes through the proton exchange membrane, is reduced into hydrogen under the action of the cathode catalyst layer, and is collected at the hydrogen outlet through the cathode special-shaped current collector.

[ technical field ] A method for producing a semiconductor device

The invention relates to the field of bipolar plates and diffusion layers of PEM hydrogen fuel cells and PEM water electrolysis cells, in particular to a special-shaped current collector, a PEM water electrolysis hydrogen production device and a water electrolysis hydrogen production method.

[ background of the invention ]

Vehicle-mounted fuel cell vehicles have been supported by the nation in recent years, and then their applications are limited by the development of hydrogen production, hydrogen storage, and fuel cell technologies, wherein PEM fuel cells and PEM hydrogen production by water electrolysis are the key technologies, and research on key materials and components in these two technologies is required to realize high performance, long service life, and low cost manufacturing.

The main components of a typical PEM water electrolysis cell comprise a cathode and anode bipolar plate, a cathode and anode diffusion layer, a cathode and anode catalytic layer, a proton exchange membrane and the like. Wherein, the bipolar plate plays a role in fixing the electrolytic cell assembly, guiding the transmission of electricity, distributing water and gas and the like; the diffusion layer plays a role in collecting current, promoting gas-liquid transfer and the like. The PEM fuel cell is the reverse process of the PEM water electrolysis cell, has similar structure, and uses different materials at the two electrodes due to different environments of the cathode and the anode.

The current research on bipolar plates has mainly focused on two aspects: in materials, various substrates are processed and prepared, various anti-corrosion coatings are coated, and the structure and the flow field are designed, and only the structure design is referred to. The bipolar plate flow channel forms include a parallel flow channel, a snake-shaped flow channel, a point-shaped flow channel, an interdigital flow channel, a bionic flow channel, a 3D structure flow channel, a composite flow channel and the like.

Chinese patent publication No. CN 105908212 a, entitled "SPE electrolytic cell module using composite flow field and method for producing hydrogen by electrolyzing water" discloses a SPE electrolytic cell module using composite flow field, which can greatly improve pure water diffusibility and bipolar plate oxygen discharge capability, and has the advantages of small along-the-way pressure drop, large flow channel area, and high working efficiency. However, this approach increases the cost of the SPE cell and increases the processing difficulty.

In PEM fuel cells and PEM water electrolysers, in many studies, titanium plate grids/meshes/felts, carbon paper and stainless steel grid plates were used as diffusion layers, but the electrochemical performance was lower than that of porous titanium plates.

Kang et al in the literature "Performance Modeling and Current Mapping of Piton exchange Membrane electrospecific Cells with Novel Thin/Tunable Liquid/Gas diffusion layers" propose a Novel Thin diffusion layer with adjustable Gas-Liquid diffusion coefficient, with a thickness reduced to 25 μm compared to conventional titanium felt. By etching round holes in the titanium foil, the diffusion layer has different straight perforations, and better performance can be obtained when the aperture is 400 μm and the porosity is 0.7.

Grigoriev et al in the literature "Optimization of porous current collectors for PEM Water Electrolaters" propose that the spherical powder for the preparation of porous titanium plates has an optimum particle size of 50 to 75 μm, and thermal sintering using titanium particles of this size gives a porous titanium diffusion layer having a porosity of 0.5, which is good in gas-liquid transport ability.

In order to solve the problems of conductivity, corrosion resistance, uniform gas-liquid distribution and the like of the bipolar plate and the diffusion layer, the problems are solved by designing the bipolar plates with different flow channel forms, preparing the diffusion layers with different structures and corrosion-resistant coatings and using different materials and processing modes, so that the cost of a PEM fuel cell and a PEM water electrolytic cell is always high. In addition, the bipolar plate and the diffusion layer are complex in components and difficult to assemble, and contact resistance between the bipolar plate and the diffusion layer increases the internal resistance of the battery, so that the problems need to be solved urgently.

Accordingly, there is a need to develop a profiled current collector, a PEM water electrolysis hydrogen production apparatus and a water electrolysis hydrogen production method to address the deficiencies of the prior art and to solve or alleviate one or more of the problems.

[ summary of the invention ]

In view of the above, the invention provides a special-shaped current collector, a PEM water electrolysis hydrogen production device and a water electrolysis hydrogen production method, wherein the special-shaped current collector is a special-shaped current collector device with the functions of a flow field plate of a fuel cell and a water electrolysis cell and a gas-liquid diffusion layer, and the purposes of cost reduction and optimization of structures of the fuel cell and the water electrolysis cell can be achieved.

In one aspect, the present invention provides a profiled collector comprising:

a first channel formed by a porous matrix;

a second channel parallel to the flow channel formed on the top surface of the porous substrate or perpendicular to the straight through hole formed on the top surface of the porous substrate;

the first channel and the second channel jointly form a gas-liquid transmission channel.

The above aspects and any possible implementation further provide an implementation manner that the porous matrix is formed by sintering stainless steel, titanium or titanium alloy composite particles with different particle sizes, and the sintered porous material has different porosities.

The above aspects and any possible implementations further provide an implementation in which the flow channel is composed of one or more of a parallel flow channel, a serpentine flow channel, a dotted flow channel, an interdigitated flow channel, and a biomimetic flow channel.

The above-described aspects and any possible implementations further provide an implementation in which the straight-perforated orifice forms include, but are not limited to, circles, triangles, and squares.

There is further provided in accordance with any one of the above aspects and possible implementations an implementation in which the profiled current collector top surface is also prepared with a corrosion-resistant conductive coating including, but not limited to, a nitride coating formed by buried nitriding, sputtered gold, and tantalum.

The above aspect and any possible implementation further provides an implementation, and the processing of the second channel includes etching, machining, and stamping.

The above aspects and any possible implementation manners further provide a PEM electrolytic water hydrogen production device, which includes a base, an anode profiled current collector, a proton exchange membrane module, a cathode profiled current collector and a top cover, which are connected in sequence, wherein PTFE gaskets are respectively arranged between the anode profiled current collector and the proton exchange membrane module and between the cathode profiled current collector and the proton exchange membrane module.

The above aspects and any possible implementation manners further provide an implementation manner, and the apparatus further includes a fastening bolt disposed at one end of the base and a fastening nut disposed at one end of the pressing sheet, the fastening bolt penetrates through the base, the anode profiled current collector, the proton exchange membrane module, the cathode profiled current collector and the top cover and is connected with the fastening nut, and a metal gasket is further disposed at one end of the cathode profiled current collector, which is close to the proton exchange membrane module.

The above aspects and any possible implementation manners further provide an implementation manner, and the PEM electrolytic water hydrogen production device is applied to a PEM water electrolysis cell or a PEM fuel cell.

The above aspect and any possible implementation manner further provide a method for producing hydrogen by electrolyzing water, which includes the following steps:

step (1): the pure water directly reaches the anode catalyst layer through the anode special-shaped current collector to generate oxygen;

step (2): oxygen returns to the anode special-shaped current collector and flows out of the water oxygen outlet together with the non-electrolyzed pure water;

and (3): the proton passes through the proton exchange membrane, is reduced into hydrogen under the action of the cathode catalyst layer, and is collected at the hydrogen outlet through the cathode special-shaped current collector.

Compared with the prior art, the invention can obtain the following technical effects: compared with the prior art, the gas-liquid transmission channel constructed by the porous matrix and the flow channel structure or the perforated structure ensures the uniform distribution of gas-liquid two-phase flow participating in the electrochemical reaction, meets the gas-liquid transmission of the membrane electrode, ensures good gas-liquid transmission performance of the membrane electrode, reduces the diffusion control link of the membrane electrode, and effectively utilizes the catalyst sites of the membrane electrode catalyst layer; on the other hand, the contact resistance between the bipolar plate and the diffusion layer in the traditional form is eliminated, and meanwhile, a flat and uniform clamping force is provided, so that the effective contact between the membrane electrode and the current collector is ensured, and the internal resistance of the electrolytic cell is reduced. The use of the novel special-shaped current collector reduces the component composition of the PEM water electrolysis cell or the PEM fuel cell, so that the PEM water electrolysis cell or the PEM fuel cell has a more compact structure and is more convenient and simpler to install, has positive influence on the performance improvement of the PEM water electrolysis cell or the PEM fuel cell, and is beneficial to the commercial application of the low-cost PEM water electrolysis cell or the PEM fuel cell.

Of course, it is not necessary for any one product in which the invention is practiced to achieve all of the above-described technical effects simultaneously.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view of a profiled collector design provided by one embodiment of the present invention;

FIG. 2 is a schematic view of a profiled collector design provided by one embodiment of the present invention;

FIG. 3 is a schematic view of a profiled collector design provided by one embodiment of the present invention;

FIG. 4 is an exploded view of a PEM water electrolysis hydrogen production device according to one embodiment of the invention;

FIG. 5 is a diagram of a process for producing hydrogen provided by an embodiment of the present invention;

FIG. 6 is a diagram illustrating the position relationship between the profiled current collector and the membrane electrode according to an embodiment of the present invention;

fig. 7 is a schematic diagram showing the relationship between the profile collector and the conventional bipolar plate + diffusion layer + membrane electrode according to an embodiment of the present invention.

Wherein the reference numbers correspond to the names: : 1-fastening bolt, 2-base, 3-anode special-shaped current collector, 4-PTFE gasket, 5-proton exchange membrane component, 6-PTFE gasket, 7-metal gasket, 8-fastening nut, 9-cathode special-shaped current collector, 10-sealing ring, 11-top cover, 12-serpentine stainless steel pressed sheet, 13-fastening nut, 14-pure water tank, 15-peristaltic pump, 16-water electrolytic cell, 17-direct current power supply, 18-gas-liquid separation device, 19-water storage tank, 20-adjustable circulating pump, 21-hydrogen drying box, 22-hydrogen storage tank, 23-oxygen drying box, 24-oxygen storage tank, 26-proton exchange membrane component, 27-anode diffusion layer, 28-cathode diffusion layer, 29-anode flow field plate, 30-cathode flow field plate.

[ detailed description ] embodiments

For better understanding of the technical solutions of the present invention, the following detailed descriptions of the embodiments of the present invention are provided with reference to the accompanying drawings.

It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The invention provides a special-shaped current collector device with the functions of a flow field plate and a gas-liquid diffusion layer of a fuel cell and a water electrolysis cell, which can achieve the purposes of cost reduction and optimization of the structures of the fuel cell and the water electrolysis cell. The invention relates to a special-shaped current collector which has the functions of a flow field plate and a gas-liquid diffusion layer of a fuel cell and a water electrolysis cell. The structure of the porous material consists of porous materials, and the surface of the porous material is provided with flow channels or straight through holes in different forms.

In the aspect of metal porous base materials, the porous material is formed by sintering stainless steel, titanium or titanium alloy composite material particles with different particle sizes, and the sintered material can be controlled to have different porosities, so that the porous material has the characteristics of good gas-liquid transmission, excellent conductivity and the like.

In terms of the structure of the metal matrix, the invention can adopt the forms of a parallel flow channel, a snake-shaped flow channel, a point-shaped flow channel, an interdigital flow channel, a bionic flow channel and a composite flow channel. And secondly, the straight perforation can be adopted, the form of the perforation comprises a circle, a triangle, a square and the like, the distribution of the straight perforation in the special-shaped current collector is controlled, and finished products with different surface porosities are obtained, wherein the porosity refers to the ratio of the area of the straight perforation to the surface area of the special-shaped current collector and is different from the porosity of the porous material.

In the aspect of the corrosion-resistant conductive coating, the surface of the special-shaped current collector is provided with a coating with excellent corrosion resistance and conductivity, such as a nitride coating formed by embedding and nitriding, sputtering gold or tantalum and the like.

The preparation and processing modes of the invention comprise the modes of thermal sintering, etching, mechanical processing, stamping and the like of the porous material.

One of the device forms described in the present invention is characterized in that: the special-shaped current collector is made of a porous titanium material with the porosity of 0.7, the whole thickness is 1mm, the surface flow channel is in a parallel flow channel form, the ridge width of the flow channel is 1mm, the ridge interval is 1mm, and the depth is 0.5 mm.

The second device form of the invention is characterized in that: the special-shaped current collector is made of a porous titanium material with the porosity of 0.7, the whole thickness is 0.5mm, a straight perforation mode is adopted, the hole type is a circular hole with the diameter of 400 mu m, and the surface porosity is up to 0.6 through uniform distribution.

The third device form of the invention is characterized in that: the special-shaped current collector is made of stainless steel material with porosity of 0.7, the whole thickness is 1mm, the surface flow channel is in the form of a composite flow channel and is composed of a parallel flow channel and a point flow channel, and on the basis, a chromium nitride coating with the thickness of 4.8 mu m is prepared in a solid nitriding mode.

Based on the structure, the invention also provides a method for producing hydrogen by electrolyzing water, which is suitable for the device and comprises the following steps:

(1) the pure water directly reaches the anode catalyst layer through the anode special-shaped current collector to generate oxygen;

(2) the oxygen returns to the anode special-shaped current collector again, flows out from the water-oxygen outlet together with the non-electrolyzed pure water, and the protons pass through the proton exchange membrane, are reduced into hydrogen under the action of the cathode catalyst layer, and are collected at the hydrogen outlet through the cathode special-shaped current collector.