阅读说明：本技术 用于电池堆的板构件 (Plate member for cell stack ) 是由 韩明 陈云中 王磊 林纯宇 于 2021-08-25 设计创作，主要内容包括：可提供一种用于电池堆的板构件、电池堆组装件、形成电池堆的板构件的方法以及组装电池堆的方法。板构件包括通道片,该通道片包括用于形成流体流动通道的至少一个峰和一个谷。两个对准部件,每个对准部件包括主体和一个或多个对准构件,主体具有设置在主体内的通孔；且其中对准部件能够沿着穿过所述对准构件的轴线将所述对准构件对准到另一个相应的对准构件；且其中通道片设置在所述两个对准部件之间。(A plate member for a cell stack, a cell stack assembly, a method of forming a plate member of a cell stack and a method of assembling a cell stack may be provided. The plate member comprises a channel sheet comprising at least one peak and one valley for forming a fluid flow channel. Two alignment components, each alignment component comprising a body and one or more alignment members, the body having a through-hole disposed within the body; and wherein an alignment member is capable of aligning the alignment member to another respective alignment member along an axis passing through the alignment member; and wherein the channel sheet is disposed between the two alignment members.)

1. A plate member for an open cathode fuel cell stack, the plate member comprising:

a corrugated channel sheet having opposing first and second side edges and opposing first and second end edges, the corrugated channel sheet comprising peaks and valleys extending from the first side edge to the second side edge, the valleys and peaks forming flow channels having openings at the first and second side edges, wherein the corrugated channel sheet comprises a corrugated channel sheet height H;

first and second alignment members, wherein the first alignment member and the second alignment member each comprise

A main body having a through-hole formed therein,

an extension on a side of the body, wherein the extension includes an alignment hole,

an alignment feature thickness T slightly less than H, an

Wherein the body comprises an end joining edge and the extension comprises a side joining edge;

wherein the first alignment member is disposed at a first end edge of the corrugated channel sheet, and the second alignment member is disposed at a second end edge of the corrugated channel sheet; and

wherein the alignment member comprises a rigid material to constrain a thickness of the plate member when assembling the fuel cell stack comprising the plurality of plate members.

2. The plate member of claim 1, wherein the end and side joining edges of the first and second alignment members enable the first and second end edge portions of the corrugated channel sheet to be tightly fitted to the first and second alignment members.

3. The plate member according to claim 1, wherein:

the first alignment part comprises

A first sealing member disposed from the first surface of the first alignment member, wherein the first sealing member surrounds the through-hole of the first alignment member, an

The first sealing component is arranged in the first sealing part; and

the second alignment member includes

A second sealing member disposed from the first surface of the second alignment member, wherein the second sealing member surrounds the through-hole of the second alignment member, an

The second seal assembly is disposed within the second seal member.

4. The plate member according to claim 2, comprising a spacer plate having first and second spacer plate surfaces provided on the first surfaces of the first and second alignment parts and the first surface of the corrugated channel plate, wherein the spacer plate comprises

A spacer through hole, wherein the spacer through hole is aligned with the through holes of the first and second alignment members, an

Wherein the first and second sealing members facilitate forming a hermetic bond with the spacer sheet and the first and second alignment members.

5. The plate member according to claim 4, comprising:

a Membrane Electrode Assembly (MEA) having first and second MEA surfaces, wherein the first MEA surface is disposed on the second surfaces of the first and second alignment members and the second surface of the corrugated channel sheet.

6. The plate member according to claim 1, comprising:

an MEA having first and second MEA surfaces, wherein the first MEA surface is disposed on the second surfaces of the first and second alignment members and the second surface of the corrugated channel sheet;

a separator sheet having first and second separator sheet surfaces, wherein the first separator sheet surface is disposed on the second MEA surface; and

wherein the first and second alignment parts, the corrugated channel sheet, the MEA, and the separator sheet form a plate member assembly.

7. The plate member according to claim 6, wherein:

the separator sheet edges are sealed to the MEA; and

the first MEA surface serves as the cathode side of the MEA and the second MEA surface serves as the anode side of the MEA.

8. The plate member of claim 6, comprising

A second separator sheet having first and second separator sheet surfaces, the second separator sheet surface of the second separator sheet being disposed on the first surfaces of the first and second alignment members and the first surface of the corrugated channel sheet; and

wherein the second separator sheet is a separator sheet of an adjacent plate member assembly of a fuel cell stack having a plurality of stacked plate assemblies.

9. The plate member according to claim 8, wherein:

the first alignment part comprises

A first sealing member disposed from the first surface of the first alignment member, wherein the first sealing member surrounds the through-hole of the first alignment member,

the first sealing component is arranged in the first sealing part; and

the second alignment member includes

A second sealing member disposed from the first surface of the second alignment member, wherein the second sealing member surrounds the through-hole of the second alignment member, an

The second sealing component is arranged in the second sealing part; and

the first and second seal assemblies facilitate forming a hermetic seal with the second spacer sheet and the first and second alignment portions.

10. The plate member according to claim 6, wherein:

the MEA is of uncompressed thickness M and recommended compression ratio CR_recThe compressible component of the plate member assembly of (a);

the spacer sheet comprises a thickness S; and

wherein the uncompressed thickness PA of the plate member assembly is equal to H + M + S.

11. The plate member of claim 10, wherein the CR is_recIncluding tolerance, wherein the minimum compression of the MEA equals CR_recTolerance and maximum compression of the MEA is CR_rec+ tolerance, wherein the compression of the MEA is below the minimum compression or above the maximum compression may negatively impact MEA performance or reliability.

12. The plate member according to claim 11, wherein:

the plate member assembly is configured to have a compressed thickness PA when assembled into a fuel cell stack_comWherein PA_comEqual to about T + M + S; and

the MEA is compressed by pressing corrugated channel sheets into the MEA, wherein the MEA is compressed to CR_rec+/-tolerance.

13. The plate member according to claim 11, wherein:

the plate member assembly is configured to have a compressed thickness PA when assembled into a fuel cell stack_comWherein PA_comEqual to about T + M + S; and

the MEA is compressed by pressing corrugated grooved sheets into the MEA, which is compressed to CR_rec。

14. The panel member of claim 1, wherein the first and second end edges include first and second end valley walls.

15. The plate member of claim 6, wherein the fuel cell stack comprises:

a bottom end plate including a bottom end plate alignment hole;

a top endplate including a top endplate alignment hole;

a plurality of plate member assemblies; and

wherein the alignment holes of the first and second alignment members of the plurality of plate member assemblies are aligned with the top and bottom end plate alignment holes to facilitate horizontal and vertical alignment of the fuel cell stack.

16. The plate member of claim 15, wherein the fuel cell stack includes an alignment rod extending vertically through the top end plate alignment hole of the top end plate, the alignment holes of the first and second alignment members of the plurality of plate member assemblies, and the bottom end plate alignment hole.

17. A method of forming an open cathode fuel cell stack comprising:

providing a plurality of plate members, wherein the plate members comprise

A corrugated channel sheet having opposing first and second side edges and opposing first and second end edges, the corrugated channel sheet comprising peaks and valleys extending from the first side edge to the second side edge, the valleys and peaks forming flow channels having openings at the first side edge and the second side edge, wherein the corrugated channel sheet comprises a corrugated channel sheet height H,

a first alignment member and a second alignment member, wherein the first alignment member and the second alignment member each comprise

A main body having a through-hole formed therein,

an extension on a side of the body, wherein the extension includes an alignment hole,

the alignment feature thickness T is slightly less than the corrugated channel sheet height H, an

Wherein the main body comprises an end joining edge and the extension comprises a side joining edge,

wherein the first alignment member is disposed at a first end edge of the corrugated channel sheet and the second alignment member is disposed at a second end edge of the corrugated channel sheet, wherein the end and side joining edges of the first and second alignment members enable the first and second end edge portions of the corrugated channel sheet to be tightly fitted to the first and second alignment members;

assembling a plurality of plate members into a stack, wherein assembling includes providing alignment posts that align with alignment holes through the plate members and exert a compressive force on the plate member stack; and

wherein the alignment member constrains a thickness of the plate member when assembled in a stack to avoid damaging the corrugated channel sheets of the plate member.

18. The method of claim 17, comprising:

providing a bottom end plate having a bottom body with bottom assembly holes configured to align with the alignment holes of the alignment features of the plurality of plate members, wherein the alignment posts are mounted in the bottom assembly holes;

providing a top endplate having a top body with a top assembly hole configured to align with the alignment holes of the alignment members of the plurality of plate members; and

the top endplate is installed through the alignment post and tightened to exert a compressive force on the plurality of plate members.

19. A method of forming a plate member for an open cell stack, comprising:

providing a corrugated channel sheet having opposing first and second side edges and opposing first and second end edges, the corrugated channel sheet comprising peaks and valleys extending from the first side edge to the second side edge, the valleys and peaks forming flow channels having openings at the first and second side edges;

providing first and second alignment members, wherein the first and second alignment members each comprise

A main body having a through-hole formed therein,

an extension on a side of the body, wherein the extension includes an alignment hole,

wherein the body comprises an end joining edge and the extension comprises a side joining edge;

mating an end-joining edge of the first alignment feature with a first end edge of the corrugated channel sheet; and

the end-joining edge of the second alignment member is mated with the second end edge of the corrugated channel sheet.

20. The method of claim 19, comprising:

providing an MEA having first and second MEA surfaces;

providing a separator sheet having first and second separator sheet surfaces;

attaching the first separator sheet surface to the second MEA surface, wherein the separator sheet edge is sealed to the MEA;

attaching a first MEA surface to the second surfaces of the first and second alignment members and the second surface of the corrugated sheet; and

wherein the first and second alignment parts, the corrugated sheet, the MEA, and the separator sheet form a plate member assembly.

Technical Field

The present disclosure relates broadly to a plate member for a cell stack and a method of forming a plate member for a cell stack.

Background

In the current art, fuel cell assemblies are increasingly being integrated to simplify stack assembly procedures and reduce costs. For example, a typical Membrane Electrode Assembly (MEA) having five layers is commonly used. Such a five-layer MEA includes a layer of Proton Exchange Membrane (PEM) sandwiched or otherwise disposed between two layers of dispersion medium, with a layer of catalyst located in both interfaces between the PEM and the dispersion medium. This arrangement integrates the membrane, electrodes and diffusion media, simplifying the stack assembly of the MEA.

However, there have been other advances with respect to other important components as stacks of bipolar plates.

The materials used have improved significantly in the PEM fuel cell industry. Conventional graphite bipolar plates are being gradually replaced by metal bipolar plates, which can be made relatively thin, thereby allowing weight and size to be reduced and power density to be increased in the stack. This is particularly advantageous for portable fuel cell and mobile use.

The use of metallic bipolar plates poses a number of new challenges. Since the metal bipolar plate is generally manufactured in a corrugated form having at least one peak and one valley, the separator sheet is used to form air flow channels and to prevent the hydrogen gas flowing in the dispersion medium from contacting the air. Sealing the hydrogen flow channels formed by the holes at the two ends of the stack is a challenge, especially when corrugated sheets are used. While alignment of the corrugated sheets, separator sheets and MEA is another challenge.

It is generally desirable that the component parts of the fuel cell, i.e., the bipolar plates, MEA, corrugated sheets, and separator sheets, have good sealing and alignment of the pore sizes. When assembled, these components form a continuous cylindrical cavity within the fuel cell and are used for internal manifolds. The hydrogen gas passes through the manifold and is uniformly dispersed to the corresponding cells. When purged from the cell, excess hydrogen is vented through another manifold similarly arranged.

It has been recognized that misregistration of all the holes in the fuel cell (i.e., between the bipolar plates, MEA, corrugated sheets, separator sheets, etc.) results in a barrier to the flow of hydrogen. This reduces the performance of the stack due to the reduction in fuel introduction. In addition, misalignment can also result in uneven distribution of hydrogen gas across each cell in the stack, which not only results in reduced overall power output, but also poor durability due to uneven voltage and heat distribution.

It has been recognized that holes in both ends of the stack are not sufficient for proper alignment. As discussed above, misalignment can affect the aesthetics of the stack as well as the power output performance.

Furthermore, the corrugated sheets used are usually coated with a noble metal, such as gold or silver, and are therefore relatively expensive. However, the areas near the two ends of the stack are not typically directly involved in the active area of the cell reaction, and this results in waste of corrugated sheet material.

Furthermore, it has been recognized that current stack assembly processes are complex due to tight sealing requirements.

In one presently known example, the MEAs are aligned within the stack. The stack is an electrochemical device comprising a fuel cell, a compressor, and an electrolyte. Compact cathode systems are used in stack assemblies. Therefore, a frame is used to position the MEA and separator sheet. The MEA is completely enclosed within the body of the frame. A sealing arrangement, such as a bead arrangement or an elastomeric seal, is required around the perimeter of the bipolar plate. The bridge is arranged outside the periphery of the opening at both ends of the frame to abut against the positioning means. These requirements for seals and bridges add complexity to the manufacturing process. In addition, tight tolerances also need to be followed during manufacture to ensure that the MEA is enclosed in the frame. Furthermore, the stack assembly in this embodiment is not safe, since the frame of the bipolar plate rests on only two positioning means.

In another presently known embodiment, the corrugated sheet is attached to the substrate with an adhesive. However, it has been recognized that when adhesives are used, there are several degrees of freedom in the manufacturing process. Therefore, it is common that tolerance limits exceeding the positioning arrangement occur during the manufacturing process, and alignment defects occur.

In another presently known embodiment, the relay unit is used in a solid oxide fuel cell. The frame and the spacer sheets in the relay unit establish a plurality of fuel flow paths and duct chambers. The ridged holes of the conduit and spacer sheet are positioned to align the stack of relay units. The relay units are stacked first without any security points being set. Thus, there is often a problem that the stacked relay units cannot be aligned properly.

In another presently known embodiment, bipolar plates are used in Molten Carbonate Fuel Cells (MCFCs). The operating temperature of the MCFC is higher than the melting point of the electrolyte material. The bipolar plate includes a plurality of raised portions to adhere the bipolar plate to the reticle to retain the current collector between the bipolar plate and the reticle. A frame is used to position the MEA and separator plates. The MEA is completely enclosed within the body of the frame. Coupling arrangements, such as protrusion and through-hole arrangements, are required around the perimeter of the bipolar plate. The requirement for such protrusions and through holes adds complexity to the manufacturing process. In addition, tight tolerances also need to be followed during manufacture to ensure that the MEA is enclosed in the frame.

Accordingly, there is a need for a plate member for a cell stack and a method of forming a plate member for a cell stack that addresses at least one of the problems described above.

Disclosure of Invention

In one embodiment, a plate member for an open cathode fuel cell stack includes a corrugated channel sheet having opposing first and second side edges and opposing first and second end edges. The corrugated channel sheet comprises peaks and valleys extending from the first side edge to the second side edge, the valleys and peaks forming flow channels having openings at the first side edge and the second side edge, and the corrugated channel sheet comprises a corrugated channel sheet height H. The plate member further includes first and second alignment components, and the first and second alignment components each include a body having a through hole, an extension on a side of the body, and the extension includes an alignment hole. The first and second alignment members each further comprise an alignment member thickness T that is slightly less than the corrugated channel sheet height H, and the body comprises an end joining edge and the extension comprises a side joining edge. The first alignment member is provided at a first end edge of the corrugated channel sheet, and the second alignment member is provided at a second end edge of the corrugated channel sheet. The alignment member is made of a rigid material that limits the thickness of the plate members when assembling a fuel cell stack including a plurality of plate members.

In another embodiment, a method of forming an open cathode fuel cell stack includes providing a plurality of plate members and the plate members include a corrugated channel sheet having opposing first and second side edges and opposing first and second end edges. The corrugated channel sheet comprises peaks and valleys extending from the first side edge to the second side edge, the valleys and peaks forming flow channels having openings at the first side edge and the second side edge, and the corrugated channel sheet comprises a corrugated channel sheet height H. The plate member further includes first and second alignment features, and the first and second alignment features each include a body having a through hole, extensions on both sides of the body, each extension including an alignment hole, an alignment feature thickness T slightly less than the height of the corrugated channel sheet. The body includes an end joining edge and the extension includes a side joining edge. The first alignment member is disposed at a first end edge of the corrugated channel sheet and the second alignment member is disposed at a second end edge of the corrugated channel sheet, the end and side joint edges of the first and second alignment members enabling the first and second end edge portions of the corrugated channel sheet to be mated to the first and second alignment members. The method also includes assembling the plurality of plate members into a stack that includes providing an alignment post that passes through an alignment hole of a plate member and exerts a compressive force on the stacked plate members. The alignment features constrain the thickness of the plate members during stack assembly to avoid damage to the corrugated channel sheets of the plate members.

In another embodiment, a method of forming a plate member for an open cell stack includes providing a corrugated channel sheet having opposing first and second side edges and opposing first and second end edges. The corrugated channel sheet includes peaks and valleys extending from the first side edge to the second side edge. The valleys and peaks form flow channels having openings at the first and second side edges. The method also includes providing first and second alignment members, each of the first and second alignment members including a body having a through-hole, an extension on a side of the body, and the extension including an alignment hole. The body includes an end joining edge and the extension includes a side joining edge. The method further includes mating an end-joining edge of the first alignment member with a first end edge of the corrugated channel sheet, and mating an end-joining edge of the second alignment member with a second end edge of the corrugated channel sheet.

These and other advantages and features of the embodiments disclosed herein will become apparent by reference to the following description and drawings. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations.

Drawings

Exemplary embodiments of the invention will be better understood and readily apparent to those skilled in the art from the following description, taken by way of example only, taken in conjunction with the accompanying drawings, in which:

fig. 1 is a front view of a plate member for a cell stack in one exemplary embodiment.

Fig. 2A is a front view of a plate member with a separator sheet removably attached in another exemplary embodiment.

Fig. 2B is a bottom view of the plate member of fig. 2A.

Fig. 3 is an exploded view of the plate member of fig. 2A and 2B.

Fig. 4A is a top view of an alignment portion in an exemplary embodiment.

Fig. 4B is an enlarged view of an alignment portion between the line X and the line Y in fig. 4A.

FIG. 5 is a front view of a corrugated sheet in an exemplary embodiment.

FIG. 6 is a close-up view of the coupling between the corrugated sheet and the alignment feature in one exemplary embodiment.

FIG. 7 is a top view of a spacer sheet in an exemplary embodiment.

Fig. 8A is a front view of the end plate.

Fig. 8B is a front view of a Membrane Electrode Assembly (MEA).

Fig. 8C is a front view of another Membrane Electrode Assembly (MEA).

Fig. 8D is a cross-sectional view of a Membrane Electrode Assembly (MEA).

Fig. 9A to 9G are schematic diagrams for explaining the steps of assembling a fuel cell stack assembly in one exemplary embodiment.

Fig. 10 is an exemplary flow chart illustrating a method of forming a plate member for a cell stack in one exemplary embodiment.

Fig. 11A-11B are perspective and cross-sectional views of one embodiment of a plate member assembly.

Fig. 12A to 12B are cross-sectional views of adjacent plate member assemblies in a cell stack assembly.

Detailed Description

The exemplary embodiments described herein are applicable to fuel cell technology and may provide a plate member for a cell stack. For example, bipolar plates may be provided, which may simplify the assembly process of a Proton Exchange Membrane Fuel Cell (PEMFC) stack, improve stacking performance, and reduce manufacturing costs.

Fig. 1 is a front view of a plate member for an open cathode cell stack in an exemplary embodiment. In the exemplary embodiment, plate member 100 includes two alignment features 102 and 104 and a channel sheet 110. In an exemplary embodiment, the channel sheet 110 includes at least one peak and one valley in the sheet body, and is in the form of a corrugated sheet. In one embodiment, the corrugated plate is made of a thin foil of SLS, aluminum, titanium, or other alloy. Other types of materials may also be used. The corrugated sheet 110 is coupled to a first alignment member 102 at a first end or edge 112 of the corrugated sheet 110 and to a second alignment member 104 at a second end or edge 114 of the corrugated sheet 110. Thus, the corrugated sheet 110 is disposed between the first and second alignment members 102, 104.

In an exemplary embodiment, each alignment feature includes a body and one or more alignment members (e.g., 116). A through hole is provided in the main body. In one embodiment, the alignment member is formed of a rigid material. In one embodiment, the alignment member is formed of a rigid material that resists compressive forces. For example, the rigid material may be a rigid plastic material that resists compressive forces. Other types of rigid materials, such as reinforced fiberglass, ceramic matrix composites, may also be used.

In an exemplary embodiment, the alignment feature can align the corrugated sheets 110 parallel to the plane of the body, and the bi and alignment member (e.g., 116) can be aligned to another corresponding alignment member (not shown) along an axis AB passing through the alignment member. For example, the alignment member may be aligned with an alignment member of another alignment member or with an end plate stacked on one of the top or bottom surfaces of the alignment member.

Fig. 2A is a front view of one embodiment of a panel member with a separator sheet removably attached thereto in another exemplary embodiment. Fig. 2B is a bottom view of the plate member of fig. 2A. Fig. 3 is an exploded view of the plate member of fig. 2A and 2B. For ease of illustration, the same reference numbers are used in fig. 2A and 2B for fig. 3.

In the exemplary embodiment, plate member 200 is substantially similar to plate member 100 of FIG. 1, plate member 200 includes first alignment features 202, second alignment features 204, corrugated sheets 210, and spacer sheets 220, respectively.

In the exemplary embodiment, first alignment member 202, second alignment member 204, bellows sheet 210, and spacer sheet 220 are removably attached to one another.

Each alignment member 202, 204 includes a through hole 232, 234, respectively. A groove or recess is provided around each through-hole 232, 234 and is considered a respective sealing member 236, 238. The spacer sheet 220 includes a pair of opposed end holes 222 and 224 symmetrically disposed in the spacer sheet 220. The corrugated sheet 210 is engaged/coupled to the first and second alignment members 202 and 204 at first and second ends/edges 212 and 212, respectively, of the corrugated sheet 210. The plate member 200 is formed by orienting the spacer sheet 220 relative to the alignment members 202, 204 such that the through-holes 232, 234 of the alignment members 202, 204 are aligned with the respective holes 222, 224 of the spacer sheet 220.

In the exemplary embodiment, each seal member 236, 238 is utilized to house a supplemental seal assembly. A supplemental sealing assembly, such as a gasket, or O-ring, is disposed in each sealing member 236, 238 (e.g., groove or pocket) to provide sealing integration. Various sealing materials may be used to form the sealing member. In one embodiment, the sealing material may comprise an elastomer, including natural or synthetic elastomers. For example, the sealing material may include rubber, fluoro elastomer (FKM), perfluoro elastomer (FFKM), silicone, fluoro rubber, ethylene propylene diene monomer, nitrile rubber, and neoprene rubber. Other types of elastomers are also possible.

After the first alignment member 202, the second alignment member 204, the corrugated sheet 210, and the spacer sheet 220 are coupled to each other, a through opening is formed through the hole 222, the corresponding sealing assembly (e.g., gasket, O-ring, etc.), and the through hole 232 at the first alignment member 202. At the second alignment member 204, another through opening is formed through the hole 224, the corresponding seal assembly, and the through hole 234.

In one embodiment, the sealing member facilitates a gas-tight arrangement with the alignment member and the spacer sheet. The plate member assembly includes a plate member having an alignment part and a corrugated sheet, a Membrane Electrode Assembly (MEA), and a separator sheet. Details of the MEA will be described later.

Typically, the MEA includes opposing first and second surfaces. The first surface contacts the plate member, such as the alignment feature and the corrugated sheet. The first surface of the MEA that is in contact with the corrugated sheets is the cathode side of the MEA. The second surface of the MEA is the anode side. The separator sheet includes opposing first and second surfaces. The first surface of the separator sheet includes an anode flow field and the second surface of the separator sheet may include a smooth surface with no flow field therein. The first surface edge of the separator sheet is sealed to the second surface of the MEA.

Depending on the configuration, the first surface of the MEA may be the top surface or the bottom surface. For example, the top surface of the MEA may contact the alignment features and the bottom surface of the corrugated sheets, and the first surface of the separator sheet is attached to the bottom surface of the MEA. Alternatively, the bottom surface of the MEA may contact the alignment features and the top surface of the corrugated sheets, and the first or bottom surface of the separator sheet is attached to the top surface of the MEA. In one embodiment, the second surface of the spacer sheet forms a gas-tight arrangement with the alignment feature of the adjacent plate member assembly. For example, the smooth surface of the spacer sheet is in surface contact with the alignment feature of the adjacent plate member having the seal assembly.

With the spacer sheet 220 sealingly disposed with the first and second alignment members 203, 204, fluid flow channels are formed by the interfit with the corrugated sheets 210. That is, a plurality of closed slots (e.g., 216) and open slots (e.g., 218) are formed and positioned in a spaced-apart manner. The closed groove 216 is a passage formed between the corrugated sheet 210 and the separator sheet 220, having openings at both ends thereof (i.e., closed through-passages when viewed from the X direction in fig. 2A). The closed slots 216 can thus serve as air flow channels for cooling the separator sheets 220, the corrugated sheets 210, and the assembled stack after assembly. The open slots 218 are open or non-closed in a direction perpendicular to the plane of the corrugated sheets 210 or perpendicular to the plane or surface of the separator sheet member 220. Thus, the air of the open channels 218 can be distributed over the diffusion media on the cathode side of the MEA, which will then adhere to the surface of the corrugated sheets 210 that expose the open channels 218.

Illustratively, the separator sheet is attached to a first or top surface of the alignment feature, while the MEA is disposed on a second or bottom surface of the alignment feature. For example, the spacer sheet is a spacer sheet of an adjacent plate member assembly. A spacer sheet is disposed on a surface of the alignment member having the seal assembly. For example, the spacer sheet of the first plate member assembly is disposed on the surface of the second plate member assembly having the alignment feature of the seal assembly. The seal assembly facilitates a hermetic seal between the spacer sheet and the alignment member.

Fig. 4A is a top view of an alignment member in an exemplary embodiment. Fig. 4B is an enlarged view of the alignment part between the line X and the line Y in fig. a.

The alignment member 400 is substantially identical to the alignment members 102 and 104 of fig. 1 and the alignment members 202 and 204 of fig. 2A-3. In the exemplary embodiment, alignment feature 400 includes a body 402, body 402 being a substantially rectangular piece, and one or more alignment members, each alignment member being disposed at one end of body 402. In this exemplary embodiment, two alignment members are provided, which are substantially circular rings. The two alignment members are provided as two alignment rings 404 and 406 symmetrically located at opposite sides or ends of the body 402. Each alignment ring 404, 406 includes an alignment hole 408, 410 and an alignment edge 412, 414; the alignment holes 408, 410 are disposed substantially in the center of the rings 404, 406.

The alignment holes 408, 410 can be aligned to another corresponding alignment member (not shown) along an axis passing through the alignment holes 408, 410. An example of an axis through the alignment hole 408 into the plane of the paper (X) is shown. For example, the alignment hole may be aligned with another alignment member (e.g., the same as the alignment member 400), or with an end plate stacked on either the top or bottom surface of the alignment member 400.

In the exemplary embodiment, alignment edges 412, 414 are substantially straight and perpendicular to a longitudinal edge or end engagement edge 420 of body 402. Each alignment edge 412, 414 extends/protrudes from a longitudinal edge 420 of the body 402 and extends in the plane of the body. With this arrangement, the alignment edges 412, 414 form a receptacle 422 that provides an engagement surface to engage the channel sheet.

The alignment member 400 also includes a through-hole 416 disposed within the body 402, the through-hole 416 being disposed substantially in the center of the body 402. A sealing member 418 in the form of a groove or recess is provided around the through-hole 416. The sealing member has a height P (not shown) and the non-sealing member has a height N (not shown). In one embodiment, the sum of P and N is equal to the thickness T of the alignment feature (not shown). It should be appreciated that another similar sealing member (not shown) may be provided around the through-hole 416 on the opposite surface of the alignment member 400 or on the opposite surface of the alignment member 400. In this case, therefore, the respective seal members are provided on the two opposing surfaces of the alignment member, respectively. With the sealing members on opposite surfaces of the alignment member, the thickness T is equal to P1 (the height of the first sealing member at the first surface of the alignment member), P2 (the height of the second sealing member at the second surface of the alignment member) and N, N is between P1 and P2. The through-holes 416 can serve as a part of a reaction gas (e.g., hydrogen) flow passage, which will be described in more detail below with reference to fig. 9G. The sealing member 418 is used to house or receive a supplemental sealing assembly, such as a gasket or O-ring, during assembly of the hermetic seal.

The alignment feature 400 may be manufactured by methods including, but not limited to, molding, casting, 3-D printing, and the like. The alignment member 400 may be made of materials including, but not limited to, metal, plastic (e.g., Acrylonitrile Butadiene Styrene (ABS), polylactic acid (PLA)), or composite materials, etc.

Fig. 5 is a front view of a corrugated sheet in an exemplary embodiment. The corrugated channel sheet 500 is the same or substantially the same as the channel sheet 110 of fig. 1 and the corrugated sheets of fig. 2A-3.

In the exemplary embodiment, corrugated channel sheet 500 is a rectangular corrugated sheet having opposing end edges (first and second end edges) and opposing side edges (first and second side edges). The side edges may be in a first or longitudinal direction and the end edges may be in a second or transverse direction. The first direction and the second direction may be perpendicular to each other. The corrugated sheet includes a plurality of valleys 502 between the end edges in the second direction. The valleys with valley walls open up and down in a spaced manner on or along the side edges. For example, a valley is formed between two peaks. The depth of each valley is substantially the same. The valleys serve as corrugated sheet flow channels.

In a preferred embodiment, the end edges of the channel sheet are flush with the valley walls of the corrugated channel sheet. For example, the end edges (valley walls) of the channel pieces are flush with the end joining edges of the alignment members. This advantageously improves the contacting of the MEA with the alignment features.

In other embodiments, the end edge includes a panel engagement lip 509. For example, the first end of the sheet includes a first sheet engaging lip and the second end of the sheet includes a second sheet engaging lip. In one embodiment, the engagement lip of the channel sheet is configured to be placed on top of the alignment member. For example, the engagement lip is placed on top of the end engagement edge of the alignment member. Alternatively, the engagement lip may be configured to be placed on the bottom of the alignment member, such as the bottom end engagement edge of the alignment member. In another embodiment, one engagement lip is configured to be placed on the top of the alignment member and the other engagement lip is configured to be placed on the bottom of the alignment member. Preferably, the engagement lip should be as small as possible. Alternatively, the edge of the engagement lip may be configured to be flush with a surface of the alignment member, such as a top or bottom surface.

The corrugated sheet 500 is formed by mechanical stamping or rolling of a metal foil, but is not limited thereto. In an exemplary embodiment, the metal foil has a thickness of, but not limited to, about 0.05mm to about 0.4 mm. The material of the foil may be, but is not limited to, stainless steel, aluminum, titanium, or other alloys. Corrugated plate 500 may be coated with a corrosion resistant layer such as a thin layer including, but not limited to, gold, silver, carbon, metal nitrides, carbides, or conductive polymers.

In an exemplary embodiment, the height of the corrugated sheet 500 is slightly greater than the thickness of the alignment member (alignment member thickness), such as 102, 104, 202, 204, 400 described above. In one embodiment, the thickness of the alignment feature is slightly less than the height of the corrugated plate, e.g., 5% to 20% less. For example, the thickness of the alignment member may be about 1.0mm, while the height of the corrugated sheet may be about 1.1 mm. In this case, the corrugated sheet is about 10% greater than the thickness of the alignment member. By making the thickness of the alignment member slightly smaller than the height of the corrugated sheets (or the height of the corrugated sheets slightly larger than the thickness of the alignment member), good contact between the MEA and the corrugated sheets of each cell of the stack after assembly is ensured to avoid high internal resistance.

In one exemplary embodiment for portable fuel cell applications, the thickness of the sheet used to form the corrugated sheet 500 is about 0.05 mm. In this embodiment, the height 504 (corrugated sheet height) is about 1.1 mm. The height 506 (transverse) is about 80.0mm and the length 508 (longitudinal) is about 150.0 mm. It should be understood that the dimensions described herein are provided for exemplary purposes and may vary significantly depending on the application.

FIG. 6 is a close-up view of the coupling between the corrugated sheet and the alignment member in an exemplary embodiment. The alignment member 602 is the same or substantially the same as the alignment member 400 in fig. 4A, and the corrugated sheet 604 is substantially the same as the corrugated sheet 500 of fig. 5. For example, the alignment member 602 includes a body having an alignment edge or extension 608.

Each end of the corrugated sheet 604 is attached to or abuts an inner longitudinal edge of two alignment members, respectively (compare longitudinal edges 420 of body 402 in fig. 4A). The longitudinal edges serve as engagement surfaces for engaging the corrugated sheets 604. In the exemplary embodiment, corrugated sheet 604 is inserted between two alignment extensions or edges of alignment member 602. For purposes of illustration, only one alignment edge 608 is shown in FIG. 6. The alignment edge forms a receptacle (compare receptacle 422 of fig. 4A). The distance between the pair of alignment edges 608 of the alignment member 602 allows the corrugated sheet 604 to be tightly held between the pair of alignment edges 608. Further, the corrugated sheet 604 may also have a hook-type arrangement by contacting the top surface of the alignment member at the longitudinal edges. Thus, the corrugated sheets 604 are held tightly between the pair of alignment members to ensure that the corrugated sheets 604 are in the correct position in the stack. The height of the corrugated sheets 604 is slightly greater than the thickness of the alignment members 602 to ensure good contact with the MEA.

In one embodiment, the corrugated sheet 604 is configured to align or flush with one of the top or bottom surfaces of the alignment member due to compressive forces after fuel cell assembly. For example, the peaks (top surfaces) or valleys (bottom surfaces) of the corrugated sheets are coplanar with the top or bottom surfaces of the alignment features. The MEA is a compressible assembly, while the corrugated sheets, spacer sheets and alignment features are not. For example, the coplanarity of the corrugated sheets with the surfaces of the alignment features may vary due to manufacturing/fabrication tolerances or processes. This may result in the corrugated sheets not being precisely aligned or flush with the surface of the alignment member.

A plate member assembly may be provided in which spacer pieces are provided on the top surfaces of the alignment members. For example, a separator sheet is attached to the bottom face of the MEA. For example, the separator sheet and the MEA are part of an adjacent plate member assembly of the cell stack. The MEA of the plate member assembly is disposed on the bottom surface of the alignment block. The separator sheets of the plate member assembly are attached to the bottom surface of the MEA.

For example, a fuel cell may include first and second plate member assemblies. The first plate member assembly includes: a) a first alignment feature at an end edge of the first corrugated sheet, the first alignment feature comprising first and second alignment feature surfaces; b) a first MEA having first and second MEA surfaces, wherein the first MEA surface is attached to the second surface of the first alignment feature; c) a first separator sheet having a first separator sheet surface attached to a second MEA surface of the first MEA. The second plate member assembly includes: a) a second alignment member located at the second corrugated sheet end edge, the second alignment member including a first alignment member surface and a second alignment member surface; b) a second MEA having first and second MEA surfaces, wherein the first MEA surface is attached to the second surface of the second alignment feature; c) a second separator sheet having a first separator sheet surface attached to a second MEA surface of the second MEA. For example, the second surface of the second separator plate of the second plate assembly may be disposed on the first surface of the first alignment feature of the first plate assembly member when stacked to assemble a fuel cell.

The bottom of the corrugated sheet is located on the MEA and is flush with the bottom surface of the alignment member prior to assembly without any compressive force being applied. However, the tops of the corrugated sheets are slightly higher than the top surface of the alignment member. For example, the top of the corrugated sheet may be 5-20% higher than the thickness of the alignment member. In this manner, the peaks of the corrugated channel sheet are disposed slightly above the tops of the alignment members.

When a compressive force is applied to the cell assembly, for example, about 5 to 20kg/cm²(-0.5-2 MPa), the corrugated sheets are pushed down by the spacer sheets due to the incompressible. This results in the peaks or tops of the corrugated sheets being flush or aligned with the top surface of the alignment member. In addition, the corrugated sheets are pushed into the MEA, compressing the MEA. For example, the valleys of the corrugated channel sheet are pushed into the MEA. Since only the MEA is considered compressible, the height of the corrugated sheet can be selected to avoid compressing the MEA beyond its limits, thereby avoiding damaging it during assembly.

FIG. 7 is a top view of a separator plate in an exemplary embodiment. The spacer sheet 700 is substantially the same as the spacer sheet in fig. 2A, 2B and 3.

A top view of the separator sheet in the exemplary embodiment. The spacer sheet 700 is substantially the same as the spacer sheet 220 in fig. 2A, 2B and 3.

In the exemplary embodiment, spacer sheet 700 includes a substantially rectangular sheet 702. A pair of holes 704, 706 are symmetrically disposed near opposite ends of the blade 702. The position of the holes 704, 706 is predetermined such that the holes 704, 706 correspond to through holes provided at the two alignment members. In the exemplary embodiment, separator sheet 700 is made of a conductive metal foil having a thickness of about 0.05mm to 0.2mm, but is not limited thereto. Alternatively, the separator sheet 700 may be made of graphite foil or the like having a thickness of about 0.3mm to 1mm, but is not limited thereto.

Fig. 10 is a schematic flow chart illustrating a method of forming a plate member for a cell stack in an exemplary embodiment. At step 1002, a channel sheet including at least one peak and one valley for forming a fluid flow channel is provided. At step 1004, two alignment features are provided, each alignment feature including a body and one or more alignment members; the body has a through hole disposed therein, and the alignment member is capable of aligning the alignment member to another corresponding alignment member along an axis passing through the alignment member. At step 1006, a channel sheet is disposed between the two alignment members. In step 1008, the channel sheet is aligned parallel to the plane of the body of each alignment member using the two alignment members.

The formation of the cell stack is described in the following introduction. The plate member is substantially similar to the plate member 200 of fig. 2A, 2B and 3, and is used as a bipolar plate for a cell stack.

Fig. 8A is a front perspective view of the end plate. The endplate 800 includes a substantially rectangular body 802, a pair of conduit holes 804, 806, two assemblies 810, 812, 814, 816, and two respective pairs of assembly holes 820, 822, 824, 826. The end plate 800 serves as a base of the cell stack. The end plate 800 serves, but is not limited to, securely holding a stack of plate members to form a stacked shape to secure accessories and the like. The conduit holes 804, 806 form part of a fuel gas (e.g., hydrogen) flow passage (fuel manifold). The material of the end plate 800 may be, but is not limited to, metal, plastic, and composite materials.

Figure 8B is one embodiment of a front view of one embodiment of a Membrane Electrode Assembly (MEA). The MEA830 is a substantially rectangular body having two through-holes 832, 834 at opposite ends of the rectangular body. Other shapes of body MEA are also possible. The MEA may be a commercially available MEA, and in this case, the detailed structure of the MEA830 is available from manufacturers such as Gore, Ballard, Johnson Matthey and Yangtze. Typically, a Proton Exchange Membrane (PEM) is sandwiched between two layers of dispersion media. One catalyst layer is located in each interface between the PEM and the dispersion medium. Thus, there are five layers of material in a typical MEA. Generally, one side of the MEA is a cathode side where air can be introduced for reaction, and the other side is an anode side for input of hydrogen fuel, depending on the catalyst used.

FIG. 8C shows a front view of another embodiment of an MEA 830. As shown, the MEA has an octagonal body with two through holes 832, 834 at opposite ends of the body. The end of the body includes a beveled edge 841 forming an octagonal body. It is also possible to provide the shaped body with other shaped bodies.

Figure 8D shows a cross-sectional view of an embodiment of a Membrane Electrode Assembly (MEA) 830. In one embodiment, the MEA includes a PEM layer 865 sandwiched between a first dispersion layer 861 and a second dispersion layer 862. At the interface between the PEM layer 865 and the first dispersion layer 861 there is a very thin first catalyst layer 863, and at the interface between the PEM layer 865 and the second dispersion layer 862 there is a very thin second catalyst layer 864.

For example, the dispersion layer or medium is a Gas Diffusion Layer (GDL). One dispersion medium having a catalyst layer serves as a cathode, and the other serves as an anode. In one embodiment, the dispersion medium contacting the separator sheet is the anode side and the dispersion medium contacting the channel sheet is the cathode side. For example, the separator sheet or layer is an electrically conductive separator sheet. The spacer sheet may be formed of an electrically conductive material, such as stainless steel, titanium, aluminum, or an alloy. The conductive material may be coated with a corrosion resistant layer, such as a thin layer of gold, silver, carbon, metal nitride or carbide, or a conductive polymer, such as a metal foil or graphite foil. Other types of conductive materials and coatings are also possible. The separator plates are configured with flow fields such as parallel flow fields, serpentine flow fields, interdigitated flow fields, or porous flow fields. Other types of flow fields are also possible. In addition, other configurations of MEAs are possible. For example, the MEA may include other layers or arrangements of layers.

In one embodiment, the dispersed layers of the MEA are compressible, while the other layers are incompressible. In the stack, the MEA is compressed to ensure intimate contact with the bipolar plates, thereby reducing the internal specific resistance. Compressibility is controlled by the dispersed layers of the MEA. Thus, the performance of the dispersion layer is critical to stack sealing and performance. Manufacturers/suppliers of Ballard, SGL, or Toray may provide information regarding the compression curve and the effect of compression on the permeability and specific resistance of the MEA. This information helps the user to optimize their stack assembly and sealing process through an overall analysis of MEA/cell/stack performance. It is thus possible to determine the maximum compression ratio of the dispersed layers of the MEA and the recommended compression ratio. The Compressibility (CR) is defined as the nominal thickness (before compression) minus the compressed thickness (final thickness). For example, for a dispersion layer having a nominal thickness of 315 μm and a recommended or recommended compression thickness of 230 μm, a Compression Ratio (CR) is recommended_rec) Will be 85 μm. For example, CR_recIs the compression at which the MEA operates optimally. The recommended compression tolerance during stack assembly is about +/-5-10%, beyond which precision MEAs or high internal resistance may be damaged, resulting in poor performance.

Fig. 9A to 9G are schematic diagrams for explaining the steps of assembling the fuel cell stack assembly in the exemplary embodiment.

In fig. 9A, rods 920, 932, 934, 936 are mounted/inserted in each assembly hole 920, 922, 924, 926 of the first end plate 900. The end plate 900 is substantially identical to the end plate 800 of fig. 8A.

In fig. 9B, a plate member 940 (e.g., 200 in fig. 2A and 2B) is assembled. The rods 930, 932, 934, 936 pass through aligned holes 942, 944, 946, 948 of the plate member 940. The separator sheet pieces (not shown) of the plate member 940 rest on the first end plate 900. The plurality of open slots (e.g., 218 in fig. 2A) face upward relative to the endplate 900. In fig. 9C, one layer of MEA950 is located/placed on top of plate member 940, with the cathode side of MEA950 facing down toward the open cell. Thus, the MEA950 abuts the top surface of the alignment feature of the plate member 940. The MEA950 may be substantially the same as MEA830 in fig. 8B or 8C. Each of the through-holes 952, 954 of the MEA950 is aligned with a respective through-opening formed by a hole of the separator sheet (e.g., 704, 706 of fig. 7), a sealing assembly (e.g., gasket, O-ring, etc.) of the plate member 940, and a through-hole 943, 945 of the alignment feature of the plate member 940.

As shown in fig. 9D and 9E, the MEA950 and the plate member 940 form a single cell. More individual cells are formed by repeating the above steps until a predetermined capacity or number of individual cells is reached.

In fig. 9F, the second end plate 960 is positioned/placed after a predetermined capacity is reached. A respective rod 930, 932, 934, 936 is mounted/inserted at each assembly hole 962, 964, 966, 968 of the second end plate 960. Thus, the cell is disposed between the two end plates 900 and 960.

In fig. 9G, the assembly of the fuel cell stack is completed by tightening nuts, e.g., 970, on the rods 930, 932, 934, 936 and installing gas connectors (not shown) in the conduit holes 904 and 906 of the first end plate 900.

After installation of other accessories, such as current collectors, wires, fans, etc., the assembled cell stack 972 can be used as a generator.

Through assembly of the cell stack 972, the corresponding apertures (e.g., 704, 706 in fig. 7) of the separator sheets, and the through-holes 943 of the component plates, the through-holes 952 of the MEAs and the conduit holes 904 are aligned and form a first fluid flow channel at one end of the stack. Similarly, at the other end of the stack, the other respective hole of the separator sheet, the through-hole 945 of the component plate, the through-hole 954 of the MEA, and the conduit hole 906 are also aligned and form a second fluid flow channel.

In an exemplary embodiment, cell stack 972 forms an open cathode assembly with unsealed through channels per corrugated sheet (compare channels viewed from arrow X in fig. 2A). The trough of each corrugated sheet forms an air flow passage for such an assembly.

In use, fuel (e.g., hydrogen) supplied from the gas connectors is delivered to the assembled cell stack 972 via the fluid flow channels. Thus, fuel flows into the dispersion medium (through the anode flow field) on the anode side of the MEA, e.g., 950. For oxidant (oxygen) supply, air is introduced into the dispersion medium on the cathode side of the MEA, e.g., 950, through a plurality of open cells (e.g., 218 in fig. 2A). Thus, electricity is generated by the electrochemical reaction between hydrogen and oxygen within the MEA, e.g., 950.

During stack assembly, a compressive force is applied to the corrugated sheets. The amount of compressive force selected should be the optimum amount of compressive force. For example, in conventional stack assembly, excessive compressive force can cause structural failure of the corrugated sheets, while insufficient compressive force can result in high internal resistance and poor electrochemical performance of the stack. In addition, the MEAs of the stack are typically fragile. The use of excessive compressive forces during assembly may crush or partially damage the dispersion media in the MEA. This in turn can affect the diffusion of reactant gases (hydrogen and oxygen) into the catalyst layers in the MEA and can compromise or even damage the fuel cell.

The plate member of the described exemplary embodiment can avoid the above-described problems. The alignment features of the plate member assembly are capable of withstanding compressive forces, thereby protecting the corrugated sheets and the dispersion medium in the MEA from damage and maintaining low resistance. Thus, the assembled fuel cell is reliable and performs optimally.

Fig. 11A-11B illustrate perspective and cross-sectional views of an embodiment of a plate member assembly 1100. The plate member assembly includes elements similar or common to those already described. Common elements may not be described or detailed. As shown, the plate member assembly includes a corrugated channel sheet 1110 disposed between first and second alignment members 1160. For example, the first alignment feature is disposed at a first end edge of the corrugated channel sheet, and the second alignment feature is disposed at a second end edge of the corrugated channel sheet. The corrugated channel sheet and the alignment member form, for example, a plate member.

The alignment member includes a body having a through hole. For example, the through-hole serves as a flow passage. The body also includes a sealing member or container. The sealing member is configured to receive a sealing assembly 1170, such as a gasket or O-ring. For example, the sealing member may be a groove or a recess surrounding the through hole. The seal assembly is configured to fit into the seal member. As shown, the seal member is configured such that the seal assembly fits into the seal member from the top surface of the alignment member. Alternatively, the seal member may be arranged such that the seal assembly fits into the seal member from the bottom surface of the alignment member.

The sealing assembly may be, for example, a gasket or an O-ring. As shown, the seal assembly is disposed within the seal member to provide hermetic integration. Various sealing materials may be used to form the sealing assembly. In one embodiment, the sealing material may comprise an elastomer, including natural or synthetic elastomers. For example, the sealing material may include rubber, fluoro elastomer (FKM), perfluoro elastomer (FFKM), silicone, fluoro rubber, ethylene propylene diene monomer, nitrile rubber, and chloroprene rubber. Other types of elastomers or sealing materials are also possible.

When the seal assembly is disposed within the seal member, it extends above (or below) the surface of the alignment member. For example, the thickness of the seal assembly is selected such that it extends G above (or below) the surface of the alignment member when fitted into the seal member_ext. For example, the total thickness G of the seal assembly is equal to G_ext+ P, P is the height of the seal member. During assembly, a compressive force is applied to compress the seal assembly to be coplanar with the surface of the alignment member. For example, the compression height G of the seal assembly_comIs P. In one embodiment, G is selected such that when the seal assembly is compressed due to assembly of the fuel cell stack, it provides a hermetic seal according to design requirements or specifications without extending excessively into the through-hole to impede or block flow and negatively impact performance.

For example, the thickness G may depend on the material used. For example, when the seal assembly is compressed so that its top surface is coplanar with the surface of the alignment member, it forms a hermetic seal with the overlying separator sheet without impeding or preventing flow. Typically, the seal assembly may be compressed by about 10-35%, depending on the material used. For example, depending on the materials used,G_extabout 10-35% of the thickness G. During assembly, the seal assembly is compressed against the surface of the alignment member.

Extensions are provided on opposite sides of the body to form alignment edges. For example, the extensions extend beyond opposite sides of the corrugated channel sheet. The body forms the end joining edges 1166 of the corrugated channel sheet ends and the extensions form the side joining edges 1168 of the side edges at the corrugated channel sheet ends. The side and end joining edges enable the ends of the corrugated channel sheet to be tightly fitted to the alignment member. This facilitates the alignment of the corrugated channel sheet with the alignment member.

In one embodiment, the alignment member is a unitary or single member. For example, various components of the alignment member, such as the main body having the through-hole and the sealing member and the extension portion, are formed as a one-piece member. In one embodiment, the alignment member is formed of a rigid material that resists compressive forces, such as a rigid plastic. The plastic alignment member may be molded. Other types of rigid materials and other molding techniques are also possible.

The extension of the body includes an alignment hole 1163. In one embodiment, the through hole is disposed between two aligned holes of the extension. The alignment posts are used to align the plate assemblies together to form a fuel cell stack assembly. The alignment features provide horizontal alignment of the plate member assemblies and vertical alignment with the plate assemblies of the cell stack assembly using the alignment posts.

In one embodiment, MEA 1130 is attached to a surface of alignment feature 1160. As shown, the MEA is disposed on the bottom surface of the alignment member with the corrugated channel sheet thereon. For example, an MEA includes a PEM layer having a catalyst layer and a dispersion medium on opposite major surfaces thereof. The surface of the MEA that is in contact with the corrugated sheets is the cathode side and the opposite side is the anode side. In one embodiment, the MEA is attached to the surface of the alignment feature opposite the surface on which the seal assembly is mounted.

The spacer sheet 1120 is removably attached to the plate member. In one embodiment, a separator sheet is attached to the anode side of the MEA. The separator sheet includes anode flow fields (e.g., parallel, serpentine, interdigitated, multi-hole type flow fields) and holes aligned with the through-holes of the alignment features of the plate member. In one embodiment, the separator sheet may be sealed to the edge of the MEA to form an anode gas chamber.

In one embodiment, the thickness T of the alignment feature is configured to be slightly less than the height H of the corrugated channel sheet. For example, the thickness of the alignment features may be about 5-20% less than the height of the corrugated channel sheet. The height H of the corrugated channel sheet, the thickness S of the separator sheet, and the thickness M of the MEA define the total thickness PA of the plate member assembly. For example, the thickness PA is the thickness (uncompressed value) of the plate member assembly without any compressive force applied. For example, PA ═ H + S + M. In one embodiment, PA does not count the height of the seal member above the alignment member surface. In the uncompressed state, T does not affect PA because H is slightly larger than T.

Under the compressive force, the MEA is compressed. For example, compression is due to the corrugated sheets being pushed into the MEA. In some cases, the compression of the MEA may include the portion of the MEA that is below the alignment feature. In one embodiment, the MEA is compressed to a nominal compressed thickness M_nomTo achieve good or optimal performance. In one embodiment, M_nomMay be defined by the MEA manufacturer. M_nomThe value of (a) can be a particular value or range of values. At M_nomIs a range, it may be taken from Mmin and Mmax. Any value outside this range may not provide good performance or function to the MEA. For example, if excessive force results in a compressed thickness below M_minOr if insufficient force results in a compressed thickness above M_maxThis may result in poor or unreliable MEA performance.

The MEA is a compression assembly of the plate member assembly, while other assemblies, such as the alignment members, the corrugated channel sheet, and the separator sheet, are not. Therefore, the fastening thickness of the plate member assembly can be limited to the thickness variation of the MEA expressed as Δ M. In one embodiment, Δ M is equal to M-M_nom。M_nomMay be a range of specific values, e.g. from M_minTo M_max。M_minTo M_maxMay be equal to M-CR_recA range of +/-tolerances (tolerances may be about 5-10%). For example, M_nomMay be equal to M-CR_recOr M-CR_rec+/-tolerance.

In addition, the method can be used for producing a composite materialWhen compressed, the corrugated sheets are pressed into the MEA. The corrugated sheets are pressed into the MEA by an amount equal to H-T. The compression amount is Δ M, for example. Δ M is equal to H-T, i.e. equal to M-M_nom. Thus, the compressed thickness PA of the plate member assembly_comCan be defined as:

PA_com＝PA–ΔM

＝H+M+S–(H–T)

＝T+M+S

for example, the assembly process of the fuel cell includes determining the overall thickness PA of the uncompressed plate member assembly. In one embodiment, PA ═ H + M + S. After PA is determined, Δ M is determined. For example,. DELTA.M-M_nomIt may be equal to H-T. The plate member assembly is then compressed by fastening the end plates to reduce the thickness of the PA by Δ M to the PA_com. Once PA is reached_comAnd stopping fastening.

In the case where the fuel cell includes a plurality of plate member assemblies for stacking fuel cells, the plate member assemblies are disposed between the end plates and fastened to the final assembly thickness PA_AcomIt can be defined as follows:

PA_Acom＝PA_comx N, where N is equal to the number of plate member assemblies.

Once PA is reached_AcomAnd stopping fastening. For example, the compression pressure is equally applied to all the MEAs of the plate member assembly. This is therefore equivalent to an average reduction in thickness of the N plate member assemblies.

Fig. 12A-12B show 2 adjacent plate member assemblies 1201 of a fuel cell stack 1200 before and after application of a compressive force_1-2. Referring to fig. 12A, the plate member assembly includes alignment members 1260 located at both ends of the corrugated sheet 1210. In an exemplary embodiment, the MEA 1230 of the plate member assembly is attached to the bottom surface of the alignment member. For example, the top surface of the MEA is attached to the bottom surface of the alignment feature. The separator sheet 1220 is attached to the bottom surface of the MEA. For example, the top surface of the separator sheet is attached to the bottom surface of the MEA. For example, the separator sheets of adjacent MEAs are attached to the top surfaces of the alignment features.

The alignment feature has a thickness T, the MEA has a thickness M, the separator plates have a thickness S and the corrugated plates have a height H. Thus, the uncompressed thickness of the plate member assembly PA is equal to H + M + S.

In fig. 12B, a compressive force is applied to the plate member assembly of the fuel cell stack. The compressive force pushes the corrugated channel sheets of the plate member assembly into the MEA. For example, the separator sheets of adjacent plate member assemblies push the corrugated channel sheet into the MEAs of the plate member assemblies. The height H of the corrugated channel sheet remains constant. In one embodiment, the compressive force causes the tops of the corrugated channel sheets to be flush with the top surface of the alignment member. For example, the top surface of the corrugated channel sheet of the lower plate member assembly is flush with the top surface of the alignment member of the lower plate member assembly. The top surface of the corrugated channel sheet of the upper plate member assembly is flush with the top surface of the alignment member of the upper plate member assembly.

In one embodiment, the thickness PA of the plate member assembly is reduced by Δ M to PA_com. For example, the MEA is compressed to a thickness by corrugated channel sheets_comWhere M is MEA_com+ Δ M. In one embodiment, H is slightly greater than T by Δ M. For example, Δ M may be equal to CR_recOr CR_rec+/-range of tolerances. For example, by CR_recOr from CR_rec+/-tolerance, H is slightly larger than T. This results in the MEA being compressed by Δ M and the top surface of the corrugated channel sheet being flush with the top surface of the alignment feature. Compressed thickness PA_comEqual to T + M + S.

In the exemplary embodiment, the holes of the respective portions of the fuel cell, for example, the plate member assembly including the alignment features, the MEA, the corrugated plate, and the separator plate, are well aligned. The aligned holes form a continuous cylindrical cavity within the fuel cell and serve as internal manifolds/channels. Hydrogen can pass through the channels and be uniformly distributed to the respective cells. For example, this channel can be viewed as a first fluid flow channel in one end of the stack of cell stack 972. Excess hydrogen purged from the cell is vented through another similar manifold. It should be understood that other impurities within the fuel cell may also be purged via the manifold. For example, the manifold/channel can be viewed as a second fluid flow channel at the other end of the stack of cell stacks 972. Exemplary embodiments may address problems caused by poor alignment in a fuel cell stack assembly due to the use of alignment members. Misregistration of the holes in the fuel cell (bipolar plates, MEA, corrugations and separator sheets, etc.) often results in a hindrance to the flow of hydrogen. The reduction in fuel ingress reduces the performance of the stack. Poor alignment may also result in uneven distribution of hydrogen to each cell in the stack. This also results in lower overall performance due to the reduction in the stoichiometric number for cells with lower hydrogen uptake.

When the plate member of the exemplary embodiment is used, the assembly process is simplified. Alignment of the individual cells is ensured due to the rods (from the end plates) passing through the respective alignment holes (alignment rings) of the plate members. By using the plate member of the described embodiment, good/precise alignment of the fuel flow channels and the active area of all cells can be achieved. This facilitates stacking performance and can increase the aesthetic appeal of the stack.

Further, by using two alignment members in the exemplary embodiment, the length of the corrugated sheet can be reduced compared to a general method in which the length of the stack is generally the same as the length of the corrugated sheet. Corrugated sheets can be coated with precious metals to prevent corrosion and therefore can be relatively expensive. The cost of stacking may be reduced by using less expensive materials, such as alignment members, instead of a portion of the corrugated sheets. Furthermore, the sealing around the gas flow channel is also simplified and significantly enhanced, since room/space is provided for the sealing assembly/material.

Example embodiments described herein may provide an open cathode assembly. Closed cathode assemblies have been used. The closed cathode assembly is provided with an oxidant flow channel and an external oxidant supply system. In contrast, open cathode assemblies operate in ambient air and are less costly and less complex to manufacture than closed cathode assemblies. Open cathode assemblies also consume less parasitic power than closed cathode assemblies.

In other exemplary embodiments, the plate members may be integrated/assembled with the MEAs prior to assembly into the stack.

Thus, in view of the above description, the described exemplary embodiments may provide an integrated bipolar plate combining a corrugated sheet and a separator sheet, and in turn provide alignment guides or measures for sealing and aligning a plurality of bipolar plates.

In the described exemplary embodiment, the corrugated sheet is described as being rectangular in shape. However, it should be understood that the exemplary embodiments are not limited thereto. For example, the corrugated sheets may be of any suitable shape, such as circular, etc.

In the described exemplary embodiments, the stack is described primarily as a fuel cell stack. However, it should be understood that example embodiments are not limited thereto, and example embodiments may extend to providing plate members for a cell stack for other suitable purposes.

In the described exemplary embodiments, the plate member may be used as a bipolar plate. However, it should be understood that example embodiments are not limited thereto, and that example embodiments may extend to providing plates for other suitable purposes.

In the described exemplary embodiments, the alignment members are described as holes. However, it should be understood that the exemplary embodiments are not limited thereto, and the alignment member may be, but is not limited to, such as having a hole protrusion arrangement protruding from a bottom surface of the alignment part to mate with a hole of a top surface of another alignment part stacked on the bottom surface of the alignment part.

Unless otherwise indicated, the terms "coupled" or "connected" as used in this specification are intended to be connected directly through one or more intermediate devices or connected through one or more intermediate devices.

In addition, when describing some embodiments, the present disclosure has disclosed methods and/or processes as a particular sequence of steps. However, unless otherwise required, it is to be understood that the method or process should not be limited to the particular sequence of steps disclosed. Other sequences of steps are possible. The particular order of the steps disclosed herein is not to be construed as an undue limitation. Unless otherwise required, the methods and/or methods disclosed herein should not be limited to the steps performed in the written order. The order of the steps may be varied and still be within the scope of the present disclosure.

Further, in the description herein, the word "substantially" is understood to include, but is not limited to, "whole" or "complete" and the like whenever used. Furthermore, terms such as "comprising," "including," and the like, when used, are intended to be inclusive and non-limiting descriptive language in that the words broadly encompass elements/components referenced after the terms, as well as other components not explicitly recited. Further, when used, terms such as "about," "approximately," and the like generally mean a reasonable variation, such as a tolerance of +/-5% of a disclosed value or a tolerance of 4% of a disclosed value, or a tolerance of 3% of a disclosed value, a tolerance of 2% of a disclosed value, or a tolerance of 1% of a disclosed value.

Further, in the description herein, certain values may be disclosed within certain ranges. Values indicating end of range are intended to illustrate preferred ranges. Whenever a range is described, it is intended that the range cover and teach all possible subranges and individual values within the range. That is, the end of a range should not be interpreted as an inflexible limitation. For example, a description of a range of 1% to 5% is intended to specifically disclose sub-ranges of 1% to 2%, 1% to 3%, 1% to 4%, 2% to 3%, etc., as well as individually, values within that range, such as 1%, 2%, 3%, 4%, and 5%. The above specific disclosure is intended to apply to any depth/width of a range.

Further, the term "hole" used in the description herein may refer to a hole, and these terms may be used interchangeably in the specification.

Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.