Separator for fuel cell and fuel cell stack

Abstract

The present invention relates to a separator for a fuel cell and a fuel cell stack. The fluid flow path (F) of the separator (10) of the fuel cell stack (16) allows the fluid to flow in the direction of the separator surface. The fluid communication hole (H) and the fluid flow path (F) are sealed by a rubber sealing member (R). The channel portion (T) and the rubber sealing member (R) intersect at an intersection (78). The channel portion (T) connects the fluid flow path (F) and the fluid communication hole (H). The first portion (72) of the rubber sealing member (R) protrudes from the plane portion (76) in the stacking direction, and the second portion (74) protrudes from the protruding end surface (Ta) of the channel portion (T) in the stacking direction.

Description

Technical Field

[0001] The present invention relates to a separator for a fuel cell and a fuel cell stack. Background Art

[0002] Generally speaking, fuel cells are used in the form of fuel cell stacks. The fuel cell stack has a single cell stack and an end plate. The single cell stack is composed of a plurality of stacked power generation cells (fuel cell monomers). The end plates are arranged at both ends of the stacking direction of the single cell stack. The power generation cell is composed of a group of separators sandwiching an electrolyte membrane-electrode structure. In addition, a compressive load (fastening load) in the stacking direction is applied to the power generation cell via the end plate.

[0003] A fluid flow path is formed in the separator for this fuel cell. The fluid flow path allows the reaction gas (oxidant gas or fuel gas) supplied to the electrolyte membrane-electrode structure to circulate. Alternatively, the fluid flow path allows a cooling medium used to cool the power generation cell to circulate. An outer area is arranged outside the fluid flow path along the surface direction of the separator. A plurality of fluid communication holes are formed in the outer area. Each fluid communication hole penetrates the power generation cell in the stacking direction of the power generation cell. Each fluid communication hole allows any of the above-mentioned oxidant gas, fuel gas, and cooling medium to circulate.

[0004] For example, as disclosed in Patent Document 1, a partition provided with a raised sealing portion is known. The raised sealing portion seals the fluid flow path and each fluid communication hole, thereby preventing leakage and mixing of the fluid. The partition is provided with a channel portion and a raised sealing portion. For example, in the case where the partition forms a fluid flow path for an oxidant gas, the raised sealing portion seals the fluid flow path and the fluid communication hole for the oxidant gas. The channel portion and the raised sealing portion intersect at an intersection. The fluid flow path for the oxidant gas is connected to the fluid communication hole for the oxidant gas by the channel portion, thereby enabling the oxidant gas to flow only between the fluid flow path for the oxidant gas and the fluid communication hole for the oxidant gas. The intersection of the raised sealing portion and the channel portion is also similarly provided between the fluid flow path for the fuel gas and the fluid communication hole for the fuel gas, and between the fluid flow path for the cooling medium and the fluid communication hole for the cooling medium.

[0005] The above-mentioned raised sealing portion and channel portion are both formed by providing a convex shape on a metal partition by stamping or the like. In a power generation cell, the protruding end face of the raised sealing portion abuts against an abutting object portion such as an electrolyte membrane-electrode structure adjacent to the protruding end face. Therefore, the raised sealing portion is applied with the above-mentioned compressive load, thereby being squeezed by the abutting object portion and elastically deformed. Thus, good sealing performance produced by the raised sealing portion can be ensured. The space formed on the inner side of the convex shape of the channel portion is a connecting path for fluid circulation. The channel portion connects the corresponding fluid flow paths and the fluid connecting holes via the connecting path.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-46755 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, it is preferred that, in the above-mentioned partition, the raised seal portion can be sufficiently elastically deformed by the compressive load. This is because the raised seal portion can well ensure the sealing between the fluid flow path and the fluid communication hole. On the other hand, it is preferred that the channel portion can suppress elastic deformation even when a compressive load is applied, thereby maintaining the cross-sectional area of ​​the inner communication path at a sufficiently large size. This is because the fluid can flow well between the corresponding fluid flow path and the fluid communication hole.

[0011] However, the above-mentioned raised seal and channel portion are formed by deforming a part of the partition. Therefore, the intersection of the raised seal and the channel portion is an integral convex shape formed continuously by the raised seal and the channel portion. In such a raised seal, the rigidity at the intersection and its vicinity is increased compared to other portions that do not intersect with the channel portion. Therefore, there is the following concern: the intersection of the raised seal and its vicinity is difficult to elastically deform compared to other portions that do not intersect with the channel portion. Furthermore, there is a concern that the sealing performance between the fluid flow path and the fluid connecting hole is reduced. On the other hand, there is the following concern: in the channel portion, the intersection and its vicinity are prone to elastic deformation in the direction of reducing the cross-sectional area of ​​the connecting path on the inside compared to other portions that do not intersect with the raised seal. Furthermore, there is a concern that it is difficult to make the fluid flow well in the channel portion.

[0012] SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems.

[0013] Solutions for solving problems

[0014] One embodiment of the present invention relates to a separator for a fuel cell, which is stacked on an electrolyte membrane-electrode structure and is subjected to a compressive load in a stacking direction, the separator for the fuel cell comprising: a fluid flow path that allows any one fluid of an oxidant gas, a fuel gas, and a cooling medium to flow in the separator surface direction; a fluid communication hole that penetrates an outer region arranged outside the fluid flow path along the separator surface direction in the stacking direction and allows the fluid to flow in the stacking direction; a rubber sealing member that seals between the fluid flow path and the fluid communication hole; and a channel portion that is hollow and protrudes from a plane portion provided in the outer region in the stacking direction, intersects and extends with the rubber sealing member at an intersection, and forms a communication path connecting the fluid flow path with the fluid communication hole on the inside, the rubber sealing member being formed by a member different from the channel portion and having a first portion and a second portion that extend continuously with each other, the first portion protruding from the plane portion in the stacking direction, and the second portion protruding from a protruding end surface of the channel portion arranged at the intersection in the stacking direction.

[0015] Another aspect of the present invention relates to a fuel cell stack, wherein a plurality of the fuel cell separators and a plurality of the electrolyte membrane-electrode structures are arranged in the stacking direction.

[0016] In the separator for fuel cells, the rubber sealing member and the channel portion are formed of different members. Therefore, for example, in comparison with a case where the rubber sealing member and the channel portion are continuously formed of the same member, elastic deformation of the rubber sealing member and the channel portion as a whole can be suppressed in the intersection portion to which a compressive load is applied.

[0017] Effects of the Invention

[0018] That is, in the rubber sealing member, it is possible to sufficiently elastically deform due to the compressive load, thereby ensuring good sealing between the fluid flow path and the fluid communication hole. On the other hand, in the channel portion, even if a compressive load is applied, the shape of the communication path with a sufficient cross-sectional area formed inside can be maintained, thereby allowing the fluid to flow well between the fluid flow path and the fluid communication hole.

[0019] As described above, according to the separator for a fuel cell and the fuel cell stack including the separator of the present invention, it is possible to ensure good sealing performance between the fluid flow path and the fluid communication hole and to allow the fluid to flow well in the communication path in the channel portion.

[0020] The above-mentioned objects, features and advantages will be easily understood by referring to the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1This is a perspective view of a fuel cell stack.

[0022] Figure 2 yes Figure 1 A partial cross-sectional view in the direction of the arrow on line II-II.

[0023] Figure 3 This is an exploded perspective view of a power generation cell.

[0024] Figure 4 This is a schematic front view of the MEA side of the first bipolar plate.

[0025] Figure 5 This is an enlarged view of the fuel gas inlet communication hole and its vicinity on the MEA side of the second bipolar plate.

[0026] Figure 6 Yes Figure 5 A three-dimensional illustration of the partition including a cross section taken along line VI-VI.

[0027] Fig. 7A yes Figure 5 A partial cross-sectional view in the direction of the arrow on line VIIA-VIIA.

[0028] Figure 7B yes Figure 5 A partial cross-sectional view taken along the VIIB-VIIB line in the direction of the arrow.

[0029] Figure 8 yes Figure 5 A partial cross-sectional view in the direction of the arrow on line VIII-VIII.

[0030] Fig. 9A It is used to explain the rubber sealing member related to the modification example. Figure 1 A partial cross-sectional view of the single cell stack in the direction of the arrow line II-II.

[0031] Fig. 9B It is used to explain the rubber sealing member related to the modification example. Figure 1 A partial cross-sectional view of the single cell stack in the direction of the arrow line II-II. DETAILED DESCRIPTION

[0032] In the following drawings, the same reference numerals are given to components that achieve the same or similar functions and effects, and overlapping descriptions may be omitted.

[0033] like Figure 1 to Figure 3 As shown, the separator 10 for the fuel cell according to the present embodiment constitutes a part of the power generation cell 12 (fuel cell monomer). Figure 1 as well as Figure 2As shown, the fuel cell stack 16 includes a power generation cell 12 in the form of a single cell stack 14 in which a plurality of power generation cells 12 are stacked in a horizontal direction (arrow A direction) or a gravity direction (arrow C direction). The fuel cell stack 16 can be appropriately applied to a fuel cell vehicle such as a fuel cell electric vehicle not shown, but is not particularly limited thereto. The fuel cell stack 16 can also be a fixed placement type, etc.

[0034] like Figure 1 as well as Figure 2 As shown, at one end of the stacking direction of the single cell stack 14 (the end in the direction of arrow symbol A1), the terminal plates 18a ( Figure 2 ), insulating member 20a and end plate 22a. At the other end of the stacking direction of the single cell stack 14 (the end in the direction of arrow symbol A2), a terminal plate 18b ( Figure 2 ), insulating member 20b and end panel 22b.

[0035] The connection plates 18a and 18b are each formed of a conductive material. Examples of the material of the connection plates 18a and 18b include metals such as copper, aluminum, or stainless steel. Figure 1 As shown, the terminal portion 24 is provided at the center or substantially at the center of each of the terminal plates 18a and 18b.

[0036] Each of the insulating members 20a and 20b is formed of an insulating material such as polycarbonate (PC) or phenolic resin. In addition, each of the insulating members 20a and 20b may be composed of a plurality of (for example, two) insulating members overlapped in the stacking direction. Figure 2 As shown in FIG. 1 , in this embodiment, a concave portion that is recessed away from the cell stack 14 is formed on the surface of the insulating member 20a that faces the cell stack 14. The terminal plate 18a is disposed in the concave portion. Figure 2 As shown, in this embodiment, a recessed portion that is recessed in a direction away from the cell stack 14 is formed on the surface of the insulating member 20b that faces the cell stack 14. The terminal plate 18b is disposed in the recessed portion.

[0037] like Figure 1As shown, each of the end panels 22a and 22b is formed into a rectangular shape having a short side along the direction of arrow symbol C and a long side along the direction of arrow symbol B. In addition, each of the end panels 22a and 22b may be formed into a rectangular shape having a short side along the direction of arrow symbol B and a long side along the direction of arrow symbol C. Between each side of the end panel 22a and each side of the end panel 22b, a connecting rod 26 extending in the stacking direction (arrow symbol A direction) is arranged. One end of each connecting rod 26 is bolted to the inner surface of the end panel 22a. The other end of each connecting rod 26 is bolted to the inner surface of the end panel 22b.

[0038] Thus, a predetermined compressive load (hereinafter referred to as "compressive load") is applied to the plurality of power generation cells 12 sandwiched between the end panels 22a and 22b in the stacking direction. In addition, the fuel cell stack 16 may also include a casing (not shown) in which the end panels 22a and 22b are used as end plates. Alternatively, the cell stack 14 may be accommodated in the casing.

[0039] like Figure 2 as well as Figure 3 As shown in FIG. 1 , in this embodiment, each power generation cell 12 includes an MEA 28 with a resin frame and a set of separators 10. The set of separators 10 sandwiches the MEA 28 with a resin frame. The MEA 28 with a resin frame includes an electrolyte membrane-electrode assembly (MEA) 30 and a resin frame member 32. Figure 2 As shown, the electrolyte membrane-electrode structure 30 includes an electrolyte membrane 34, an anode electrode 36, and a cathode electrode 38. The anode electrode 36 is provided on one surface of the electrolyte membrane 34 (the surface facing the direction of the arrow symbol A2). The cathode electrode 38 is provided on the other surface of the electrolyte membrane 34 (the surface facing the direction of the arrow symbol A1).

[0040] The electrolyte membrane 34 is a solid polymer electrolyte membrane (cation exchange membrane) such as a thin film of perfluorosulfonic acid containing water. The electrolyte membrane 34 is sandwiched between the anode electrode 36 and the cathode electrode 38. The electrolyte membrane 34 can use a HC (hydrocarbon) electrolyte in addition to a fluorine-based electrolyte.

[0041] The cathode electrode 38 includes a cathode electrode catalyst layer 38a and a cathode gas diffusion layer 38b. The cathode electrode catalyst layer 38a is joined to the surface of the electrolyte membrane 34 facing the direction of the arrow symbol A1. The cathode gas diffusion layer 38b is stacked on the cathode electrode catalyst layer 38a. The anode electrode 36 includes an anode electrode catalyst layer 36a and an anode gas diffusion layer 36b. The anode electrode catalyst layer 36a is joined to the surface of the electrolyte membrane 34 facing the direction of the arrow symbol A2. The anode gas diffusion layer 36b is stacked on the anode electrode catalyst layer 36a. In the present embodiment, the anode gas diffusion layer 36b has a larger plane size (outer dimensions) than the electrolyte membrane 34, but is not particularly limited thereto. In the present embodiment, the cathode gas diffusion layer 38b has a larger plane size (outer dimensions) than the electrolyte membrane 34, but is not particularly limited thereto.

[0042] The cathode electrode catalyst layer 38a is formed by, for example, uniformly coating the surface of the cathode gas diffusion layer 38b with porous carbon particles carrying a platinum alloy and an ion conductive polymer binder. The anode electrode catalyst layer 36a is formed by, for example, uniformly coating the surface of the anode gas diffusion layer 36b with porous carbon particles carrying a platinum alloy and an ion conductive polymer binder.

[0043] The cathode gas diffusion layer 38b and the anode gas diffusion layer 36b are each formed of a conductive porous sheet such as carbon paper or carbon cloth. Alternatively, a conductive porous layer (not shown) may be provided between at least one of the cathode electrode catalyst layer 38a and the cathode gas diffusion layer 38b and between the anode electrode catalyst layer 36a and the anode gas diffusion layer 36b.

[0044] The resin frame member 32 is in the shape of a frame. For example, the inner peripheral edge of the resin frame member 32 is joined to the outer peripheral edge of the electrolyte membrane-electrode structure 30. The electrolyte membrane 34 is relatively expensive, and thus, by providing the resin frame member 32 on the outer periphery of the electrolyte membrane-electrode structure 30, the area of ​​the electrolyte membrane 34 required to form one power generation cell 12 can be reduced.

[0045] The bonding structure of the resin frame member 32 and the electrolyte membrane-electrode structure 30 is not particularly limited. The bonding structure may be, for example, a structure in which the inner peripheral edge of the resin frame member 32 is clamped between the outer peripheral edge of the cathode gas diffusion layer 38b and the outer peripheral edge of the anode gas diffusion layer 36b. In this case, the inner peripheral end surface of the resin frame member 32 may also be close to the outer peripheral end surface of the electrolyte membrane 34. The inner peripheral end surface of the resin frame member 32 abuts against the outer peripheral end surface of the electrolyte membrane 34. The inner peripheral end surface of the resin frame member 32 may also overlap with the outer peripheral end surface of the electrolyte membrane 34.

[0046] The above-mentioned joint structure can be changed as follows. The outer peripheral edge of the electrolyte membrane 34 is made to protrude outward from the cathode gas diffusion layer 38b. The outer peripheral edge of the electrolyte membrane 34 is made to protrude outward from the anode gas diffusion layer 36b. Frame-shaped films are provided on both sides of the outer peripheral edge of the electrolyte membrane 34, thereby forming a resin frame member 32. That is, the resin frame member 32 can also be formed by stacking a plurality of frame-shaped films and bonding them with an adhesive or the like. Moreover, in the case where the electrolyte membrane 34 is made to protrude outward, the power generation cell 12 may not have the resin frame member 32.

[0047] like Figure 1 As shown, one oxidant gas inlet communication hole 40a, two cooling medium inlet communication holes 42a, and two fuel gas outlet communication holes 44b are provided at one edge of the long side direction of each of the power generation cell 12, the end plate 22a, and the insulating members 20a, 20b (edge ​​in the direction of arrow symbol B1). One fuel gas inlet communication hole 44a, two cooling medium outlet communication holes 42b, and two oxidant gas outlet communication holes 40b are provided at the other edge of the long side direction of each of the power generation cell 12, the end plate 22a, and the insulating members 20a, 20b (edge ​​in the direction of arrow symbol B2).

[0048] Fuel gas (e.g., hydrogen-containing gas) is discharged from the fuel gas outlet passage 44b. Oxidant gas (e.g., oxygen-containing gas) is supplied to the oxidant gas inlet passage 40a. Cooling medium (e.g., at least one of pure water, ethylene glycol, oil, etc.) is supplied to the cooling medium inlet passage 42a. Fuel gas is supplied to the fuel gas inlet passage 44a. Cooling medium is discharged from the cooling medium outlet passage 42b. Oxidant gas is discharged from the oxidant gas outlet passage 40b.

[0049] The oxidant gas inlet communication hole 40a, the cooling medium inlet communication hole 42a, the fuel gas outlet communication hole 44b, the fuel gas inlet communication hole 44a, the cooling medium outlet communication hole 42b, and the oxidant gas outlet communication hole 40b are collectively referred to as "fluid communication holes H". The fluid communication holes H connect the fuel cell stack 16 in the stacking direction except for the terminal plates 18a and 18b ( Figure 2 ) The portion other than the end panel 22b is penetrated.

[0050] Moreover, the fuel gas inlet connecting hole 44a and the fuel gas outlet connecting hole 44b are collectively referred to as "fuel gas connecting holes 44a, 44b". The oxidant gas inlet connecting hole 40a and the oxidant gas outlet connecting hole 40b are collectively referred to as "oxidant gas connecting holes 40a, 40b". In addition, the coolant inlet connecting hole 42a and the coolant outlet connecting hole 42b are collectively referred to as "coolant connecting holes 42a, 42b".

[0051] These fluid communication holes H are arranged in the vertical direction (directions of arrows C1 and C2). Figure 3 As shown, two fuel gas outlet passages 44b are disposed in a vertically spaced relationship at one end portion (the edge in the direction of arrow symbol B1) of the power generation unit cell 12 in the long side direction. Two cooling medium inlet passages 42a are disposed in a vertically spaced relationship between the two fuel gas outlet passages 44b. An oxidant gas inlet passage 40a is disposed between the two cooling medium inlet passages 42a.

[0052] Two oxidant gas outlet passages 40b are disposed vertically and spaced apart from each other at the other end (the edge in the direction of arrow symbol B2) of the power generation unit cell 12 in the longitudinal direction. Two coolant outlet passages 42b are disposed vertically and spaced apart from each other between the two oxidant gas outlet passages 40b. A fuel gas inlet passage 44a is disposed between the two coolant outlet passages 42b.

[0053] Moreover, the fluid communication holes H are not limited to the above-mentioned configuration and number, and the fluid communication holes H can be set to a configuration and number corresponding to the required specifications. For example, the fuel gas outlet communication hole 44b can be set to one. The oxidant gas outlet communication hole 40b can also be set to one. The cooling medium inlet communication hole 42a can also be set to one. The cooling medium outlet communication hole 42b can also be set to one.

[0054] In addition, in this embodiment, for example, Figure 4 , Figure 5 As shown, the shape of each fluid communicating hole H when viewed from the stacking direction (the direction of the arrow symbol A) is a hexagon, but is not particularly limited to this. For example, the shape of each fluid communicating hole H when viewed from the stacking direction may also be a polygon other than a hexagon, or may also be a rounded polygon other than a hexagon. The shape of each fluid communicating hole H when viewed from the stacking direction may also be a circle. In this case, it is preferred that, in each fluid communicating hole H, the edge adjacent to the outer edge of the partition 10 when viewed from the stacking direction is set to a straight line along the outer edge of the partition 10. For example, compared with the case where the above-mentioned edge of each fluid communicating hole H is bent or curved relative to the outer edge of the partition 10, it can be configured so that the above-mentioned edge of each fluid communicating hole H is close to the outer edge of the partition 10 as a whole. Thereby, it is possible to avoid the formation of excess space between each fluid communicating hole H and the outer edge of the partition 10. Furthermore, the area of ​​each fluid communicating hole H can be maintained, and the partition 10 can be miniaturized.

[0055] like Figure 3As shown, the separator 10 is formed by stacking a first bipolar plate 48 and a second bipolar plate 50. The outer periphery of the first bipolar plate 48 and the outer periphery of the second bipolar plate 50 are joined together by welding, brazing or caulking. The first bipolar plate 48 and the second bipolar plate 50 are each formed of a metal material such as a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a thin plate in which a surface treatment for corrosion prevention is applied to the surface of the metal material. The first bipolar plate 48 and the second bipolar plate 50 are each formed by stamping the cross section of the thin plate into a corrugated shape. Moreover, the separator 10 is not limited to a separator formed by joining the first bipolar plate 48 and the second bipolar plate 50. The separator 10 can also be composed of a single metal plate (bipolar plate).

[0056] The first bipolar plate 48 has an MEA side surface 48a facing the MEA 28 with a resin frame and a refrigerant side surface 48b on the back thereof. The second bipolar plate 50 has an MEA side surface 50a facing the MEA 28 with a resin frame and a refrigerant side surface 50b on the back thereof.

[0057] like Figure 4 As shown, a plurality of protrusions extending linearly in the direction of arrow symbol B are provided on the MEA side surface 48a of the first bipolar plate 48. An oxidant gas flow path 52 is formed in the grooves between the plurality of protrusions. Moreover, the protrusions may also be wavy. The oxidant gas flow path 52 is connected to an oxidant gas inlet connecting hole 40a via an oxidant gas channel portion 54 described later so that fluid can flow. The oxidant gas flow path 52 is connected to two oxidant gas outlet connecting holes 40b via an oxidant gas channel portion 54 described later so that fluid can flow. Therefore, the oxidant gas flow path 52 allows the oxidant gas to flow in the direction of the partition surface (the direction of arrow symbol B, the direction of arrow symbol C).

[0058] like Figure 3 As shown, a plurality of protrusions extending linearly in the direction of arrow symbol B are provided on the MEA side 50a of the second bipolar plate 50. A fuel gas flow path 56 is formed in the grooves between the plurality of protrusions. Moreover, the protrusions may also be wavy. The fuel gas flow path 56 is connected to a fuel gas inlet connecting hole 44a via a fuel gas channel portion 58 described later so that fluid can flow. The fuel gas flow path 56 is connected to two fuel gas outlet connecting holes 44b via a fuel gas channel portion 58 described later so that fluid can flow. Thus, the fuel gas flow path 56 allows the fuel gas to flow in the direction of the separator surface.

[0059] In the separator 10, the refrigerant side 48b of the first bipolar plate 48 and the refrigerant side 50b of the second bipolar plate 50 face each other. A cooling medium flow path 60 is formed between these refrigerant side 48b and refrigerant side 50b. The back shape of the MEA side 48a of the first bipolar plate 48 overlaps with the back shape of the MEA side 50a of the second bipolar plate 50 to form the cooling medium flow path 60. The cooling medium flow path 60 is connected to the two cooling medium inlet connecting holes 42a through the cooling medium channel portion 62 described later so that fluid can flow. The cooling medium flow path 60 is connected to the two cooling medium outlet connecting holes 42b through the cooling medium channel portion 62 described later so that fluid can flow. Therefore, the cooling medium flow path 60 allows the cooling medium to flow in the separator surface direction.

[0060] Hereinafter, the oxidant gas flow path 52 , the fuel gas flow path 56 , and the coolant flow path 60 are collectively referred to as a fluid flow path F. In addition, the oxidant gas passage portion 54 , the fuel gas passage portion 58 , and the coolant passage portion 62 are collectively referred to as a passage portion T.

[0061] like Figure 4 As shown in FIG. 1 , an outer region 64 is provided outside the oxidant gas flow path 52 and the cooling medium flow path 60 of the first bipolar plate 48 in the separator surface direction. Figure 3 As shown, in the separator surface direction, the outer region 64 is provided outside the fuel gas flow path 56 and the coolant flow path 60 of the second bipolar plate 50. When viewed from the stacking direction, the outer region 64 faces the outer portion of the resin framed MEA 28 than the anode electrode 36 and the cathode electrode 38.

[0062] The fluid communication hole H is provided in the outer region 64. In each separator 10, the periphery of the fluid communication hole H of the first bipolar plate 48 (except the channel portion T) and the periphery of the fluid communication hole H of the second bipolar plate 50 (except the channel portion T) face each other in the stacking direction. Alternatively, the periphery of the fluid communication hole H of the first bipolar plate 48 (except the channel portion T) and the periphery of the fluid communication hole H of the second bipolar plate 50 (except the channel portion T) may be joined by welding or brazing.

[0063] like Figure 2 as well as Figure 3 As shown, a communicating hole rubber sealing member 66 ( Figure 3 )、Reaction gas rubber seal member 68、Outer peripheral seal 70 ( Figure 3 The communicating hole rubber sealing member 66, the reaction gas rubber sealing member 68 and the peripheral seal 70 of the first bipolar plate 48 protrude from the MEA side surface 48a toward the MEA 28 with the resin frame in the stacking direction. The communicating hole rubber sealing member 66 ( Figure 3 )、Reaction gas rubber seal member 68、Outer peripheral seal 70 ( Figure 3 ). The through hole rubber seal member 66, the reaction gas rubber seal member 68 and the peripheral seal 70 of the second bipolar plate 50 protrude from the MEA side surface 50a toward the MEA 28 with a resin frame in the stacking direction. The through hole rubber seal member 66 and the reaction gas rubber seal member 68 are collectively referred to as a rubber seal member R.

[0064] The rubber sealing member R provided on the first bipolar plate 48 is referred to as a first rubber sealing member R1. The rubber sealing member R provided on the second bipolar plate 50 is referred to as a second rubber sealing member R2. In the case where the first rubber sealing member R1 and the second rubber sealing member R2 are not distinguished from each other, they are collectively referred to as a rubber sealing member R. In the present embodiment, the first rubber sealing member R1 and the second rubber sealing member R2 are set to have the same or substantially the same shape and size. That is, in the present embodiment, the width of the first rubber sealing member R1 perpendicular to the extension direction and the width of the second rubber sealing member R2 perpendicular to the extension direction are set to be the same or substantially the same.

[0065] like Figure 2 As shown, the first rubber seal member R1 and the peripheral seal 70 ( Figure 3 ), and protrudes in the direction opposite to the second bipolar plate 50 that constitutes the separator 10 together with the first bipolar plate 48. The second rubber seal member R2 and the peripheral seal 70 ( Figure 3 ), protruding in a direction opposite to the first bipolar plate 48 that constitutes the separator 10 together with the second bipolar plate 50.

[0066] In the separator 10, the position of the first rubber seal member R1 when viewed in the stacking direction is set to overlap with the position of the second rubber seal member R2 when viewed in the stacking direction. The position of the outer peripheral seal 70 of the first bipolar plate 48 when viewed in the stacking direction is set to overlap with the position of the outer peripheral seal 70 of the second bipolar plate 50 when viewed in the stacking direction.

[0067] Therefore, in the present embodiment, the front end portion of the first rubber seal member R1 of the first bipolar plate 48 in the protruding direction abuts against the front end portion of the second rubber seal member R2 of the second bipolar plate 50 constituting the other adjacent separator 10, with the resin frame member 32 interposed therebetween. The outer peripheral seal 70 ( Figure 3 ) is in contact with a front end portion in the protruding direction of the outer peripheral seal 70 of the second bipolar plate 50 constituting another adjacent separator 10, with the resin frame member 32 interposed therebetween.

[0068] like Figure 3 as well as Figure 4 As shown, the rubber sealing member R seals the fluid flow path F and the fluid communication hole H. The rubber sealing member R is formed of a material having rubber elasticity. As an example of a material having rubber elasticity, various resin elastomers (e.g., silicone rubber, fluororubber) and vulcanized rubber can be cited. The communication hole rubber sealing members 66 surround the fluid communication hole H individually. The reaction gas rubber sealing member 68 surrounds the fluid flow path F, the oxidant gas communication holes 40a, 40b, and the fuel gas communication holes 44a, 44b as a whole.

[0069] like Figure 2 , Figures 5 to 7A , Figure 7B As shown, in this embodiment, two through-hole rubber sealing members 66 are arranged side by side in the partition surface direction as a set (double layer). Two reaction gas rubber sealing members 68 are arranged side by side in the partition surface direction as a set (double layer). Figure 3 as well as Figure 4 In the figure, for the convenience of illustration, a rubber sealing component R is used to represent it.

[0070] In this embodiment, two rubber sealing members R arranged in a group in the partition surface direction have the same shape. Fig. 7A as well as Figure 7B As shown in FIG. 1 , in a state before the fuel cell stack 16 is assembled (a state where no compressive load is applied), the front end surface Ra of each rubber sealing member R in the protruding direction is an arc-shaped protruding direction from the base end toward the front end. In addition, the width of the rubber sealing member R perpendicular to the extending direction decreases from the base end toward the front end in the protruding direction. Fig. 7A as well as Figure 7B The rubber seal member R shown in other drawings is in a state of being elastically deformed by receiving a compressive load.

[0071] The shape of the rubber sealing member R is not limited to the above. For example, the front end surface Ra of each rubber sealing member R in the protruding direction may be flat when no compressive load is applied. In addition, two rubber sealing members R arranged side by side in a group in the partition surface direction may have different shapes from each other.

[0072] like Figures 4 to 7A , Figure 7B As shown, the communication hole rubber seal member 66 has a first portion 72 and a second portion 74. The reaction gas rubber seal member 68 has a first portion 72 and a second portion 74. The first portion 72 and the second portion 74 will be described in detail later.

[0073] like Figure 3As shown, the peripheral seal 70 surrounds the outer peripheral edge of the partition 10. Alternatively, the peripheral seal 70 may be formed of a material having the same rubber elasticity as the rubber seal member R. The peripheral seal 70 may also be a raised seal formed by stamping or the like. When the peripheral seal 70 is formed of a material having rubber elasticity, the peripheral seal 70 may be arranged in pairs in the partition surface direction as a group, as with the rubber seal member R, or may be arranged in pairs of three or more, or may be composed of one. In addition, the peripheral seal 70 may not be provided.

[0074] like Figures 4 to 7A , Figure 7B As shown in FIG. 1 , a plane portion 76 is provided in the outer region 64 of the partition plate 10 . A channel portion T is provided in the plane portion 76 . The channel portion T intersects and extends with the rubber sealing member R at the intersection portion 78 . Specifically, the channel portion T is provided at Figure 4 The channel portion T is provided on the plane portion 76 of the first bipolar plate 48. Figure 5 The planar portion 76 of the second bipolar plate 50 .

[0075] The channel portion T provided on the plane portion 76 of the first bipolar plate 48 is formed by, for example, the first bipolar plate 48 being integrally bulged out by stamping. The channel portion T provided on the plane portion 76 of the second bipolar plate 50 is formed by, for example, the second bipolar plate 50 being integrally bulged out by stamping. That is, the rubber sealing member R formed of a material having rubber elasticity and the channel portion T formed by a portion of the partition 10 are formed by different members. In addition, as Figure 6 , Figure 7B , Figure 8 As shown, the channel portion T is hollow and protrudes from the MEA side surfaces 48 a and 50 a of the flat portion 76 in the same direction as the protruding direction of the rubber seal member R.

[0076] In the separator 10, the position of the channel portion T provided in the first bipolar plate 48 in the stacking direction overlaps with the position of the channel portion T provided in the second bipolar plate 50 in the stacking direction. That is, the hollow portion inside the channel portion T provided in the first bipolar plate 48 and the hollow portion inside the channel portion T provided in the second bipolar plate 50 are connected to each other.

[0077] like Figure 4As shown in the figure, when viewed from the separator thickness direction (stacking direction, arrow A direction), the oxidant gas channel portion 54 extends between the oxidant gas communication hole 40a and the fluid flow path F. The oxidant gas channel portion 54 intersects with the communication hole rubber sealing member 66 surrounding the oxidant gas communication hole 40a at the intersection 78. When viewed from the separator thickness direction (stacking direction, arrow A direction), the oxidant gas channel portion 54 extends between the oxidant gas communication hole 40b and the fluid flow path F. The oxidant gas channel portion 54 intersects with the communication hole rubber sealing member 66 surrounding the oxidant gas communication hole 40b at the intersection 78. In the extension direction of the oxidant gas channel portion 54, at the end of the oxidant gas channel portion 54 close to the oxidant gas communication hole 40a, a communication hole side opening 80 opening toward the oxidant gas communication hole 40a is provided. In the extending direction of the oxidant gas passage portion 54 , at an end portion of the oxidant gas passage portion 54 close to the oxidant gas communication hole 40 b , a communication hole side opening 80 opening toward the oxidant gas communication hole 40 b is provided.

[0078] On the other hand, in the extension direction of the oxidant gas channel portion 54 provided in the first bipolar plate 48, at the end of the oxidant gas channel portion 54 close to the oxidant gas flow path 52, a flow path side opening 82 is provided which opens toward the oxidant gas flow path 52. In the extension direction of the oxidant gas channel portion 54 provided in the second bipolar plate 50, the end of the oxidant gas channel portion 54 close to the fuel gas flow path 56 is closed. Alternatively, the plane portion 76 of the periphery of the oxidant gas channel portion 54 on the refrigerant side 48b and the plane portion 76 of the periphery of the oxidant gas channel portion 54 on the refrigerant side 50b may be joined by welding. Alternatively, the plane portion 76 of the periphery of the oxidant gas channel portion 54 on the refrigerant side 48b and the plane portion 76 of the periphery of the oxidant gas channel portion 54 on the refrigerant side 50b may be joined by brazing.

[0079] Therefore, a communication path is formed inside the oxidant gas channel portion 54 so that the oxidant gas communication hole 40a communicates with the oxidant gas flow path 52. A communication path is formed inside the oxidant gas channel portion 54 so that the oxidant gas communication hole 40b communicates with the oxidant gas flow path 52. This communication path does not allow the fluid flow path F (fuel gas flow path 56 and coolant flow path 60) other than the oxidant gas flow path 52 to communicate with the oxidant gas communication hole 40a. This communication path does not allow the fluid flow path F (fuel gas flow path 56 and coolant flow path 60) other than the oxidant gas flow path 52 to communicate with the oxidant gas communication hole 40b.

[0080] In the present embodiment, three oxidant gas channel portions 54 are arranged in one oxidant gas communicating hole 40a. Three oxidant gas channel portions 54 are arranged in one oxidant gas communicating hole 40b. However, the number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40a is not particularly limited. The number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40a may also be one. The number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40a may also be multiple other than three. The number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40b is not particularly limited. The number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40b may also be one. The number of oxidant gas channel portions 54 arranged in one oxidant gas communicating hole 40b may also be multiple other than three.

[0081] like Figure 3 as well as Figure 5 As shown, when viewed from the separator thickness direction, the fuel gas channel portion 58 extends between the fuel gas communication hole 44a and the fluid flow path F. The fuel gas channel portion 58 and the communication hole rubber sealing member 66 surrounding the fuel gas communication hole 44a are connected at the intersection 78 ( Figure 5 ) intersects at the intersection 78 ( ). When viewed from the thickness direction of the separator, the fuel gas channel portion 58 extends between the fuel gas connecting hole 44b and the fluid flow path F. The fuel gas channel portion 58 and the connecting hole rubber sealing member 66 surrounding the fuel gas connecting hole 44b are at the intersection 78 ( Figure 5 In the extending direction of the fuel gas channel portion 58, at the end of the fuel gas channel portion 58 close to the fuel gas connecting hole 44a, a connecting hole side opening 80 ( Figure 5 In the extending direction of the fuel gas channel portion 58, at the end of the fuel gas channel portion 58 close to the fuel gas connecting hole 44b, a connecting hole side opening 80 ( Figure 5 ).

[0082] On the other hand, in the extending direction of the fuel gas channel portion 58 provided in the second bipolar plate 50, at the end of the fuel gas channel portion 58 close to the fuel gas flow path 56, a flow path side opening 82 ( Figure 5 ). In the extension direction of the fuel gas channel portion 58 provided in the first bipolar plate 48, the end of the fuel gas channel portion 58 close to the oxidant gas flow path 52 is blocked. Alternatively, the plane portion 76 of the periphery of the fuel gas channel portion 58 on the refrigerant side 48b and the plane portion 76 of the periphery of the fuel gas channel portion 58 on the refrigerant side 50b may be joined by welding or brazing.

[0083] Therefore, a communication passage is formed inside the fuel gas channel portion 58 so that the fuel gas communication hole 44a communicates with the fuel gas flow path 56. A communication passage is formed inside the fuel gas channel portion 58 so that the fuel gas communication hole 44b communicates with the fuel gas flow path 56. The communication passage does not communicate the fluid flow path F (oxidant gas flow path 52 and coolant flow path 60) other than the fuel gas flow path 56 with the fuel gas communication hole 44a. The communication passage does not communicate the fluid flow path F (oxidant gas flow path 52 and coolant flow path 60) other than the fuel gas flow path 56 with the fuel gas communication hole 44b.

[0084] In the present embodiment, three fuel gas channel portions 58 are arranged in one fuel gas connecting hole 44a. Three fuel gas channel portions 58 are arranged in one fuel gas connecting hole 44b. However, the number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44a is not particularly limited. The number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44a may also be one. The number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44a may also be multiple other than three. The number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44b is not particularly limited. The number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44b may also be one. The number of fuel gas channel portions 58 arranged in one fuel gas connecting hole 44b may also be multiple other than three.

[0085] like Figure 3 As shown, when viewed from the thickness direction of the partition, the cooling medium channel portion 62 extends between the cooling medium connecting hole 42a and the fluid flow path F. The cooling medium channel portion 62 intersects with the connecting hole rubber sealing member 66 surrounding the cooling medium connecting hole 42a at an intersection 78. When viewed from the thickness direction of the partition, the cooling medium channel portion 62 extends between the cooling medium connecting hole 42b and the fluid flow path F. The cooling medium channel portion 62 intersects with the connecting hole rubber sealing member 66 surrounding the cooling medium connecting hole 42b at an intersection 78. The cooling medium channel portion 62 intersects with the reaction gas rubber sealing member 68 at the intersection 78. In the extending direction of the cooling medium channel portion 62, at the end of the cooling medium channel portion 62 close to the cooling medium connecting hole 42a, a connecting hole side opening 80 (opening toward the cooling medium connecting hole 42a) is provided. Figure 4 In the extending direction of the cooling medium channel portion 62, at the end of the cooling medium channel portion 62 close to the cooling medium communication hole 42b, a communication hole side opening 80 ( Figure 4 ).

[0086] On the other hand, Figure 4As shown, in the extension direction of the cooling medium channel portion 62 provided in the first bipolar plate 48, the end of the cooling medium channel portion 62 close to the oxidant gas flow path 52 is blocked. Figure 3 In the extension direction of the cooling medium channel portion 62 provided on the second bipolar plate 50, the end of the cooling medium channel portion 62 close to the fuel gas flow path 56 is blocked. In addition, the end of the cooling medium channel portion 62 in the refrigerant side surface 48b of the first bipolar plate 48 close to the cooling medium flow path 60 is connected to the cooling medium flow path 60 via a gap (not shown) formed between the refrigerant side surfaces 48b and 50b of the first bipolar plate 48 and the second bipolar plate 50. The end of the cooling medium channel portion 62 in the refrigerant side surface 50b of the second bipolar plate 50 close to the cooling medium flow path 60 is connected to the cooling medium flow path 60 via a gap (not shown) formed between the refrigerant side surfaces 48b and 50b of the first bipolar plate 48 and the second bipolar plate 50.

[0087] Therefore, a communication path that connects the cooling medium communication holes 42a and 42b with the cooling medium flow path 60 is formed inside the cooling medium channel portion 62. This communication path does not connect the fluid flow path F (oxidant gas flow path 52 and fuel gas flow path 56) other than the cooling medium flow path 60 with the cooling medium communication hole 42a. This communication path does not connect the fluid flow path F (oxidant gas flow path 52 and fuel gas flow path 56) other than the cooling medium flow path 60 with the cooling medium communication hole 42b.

[0088] In the present embodiment, three cooling medium channel portions 62 are arranged in one cooling medium connecting hole 42a. Three cooling medium channel portions 62 are arranged in one cooling medium connecting hole 42b. However, the number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42a is not particularly limited. The number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42a may also be one. The number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42a may also be multiple other than three. The number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42b is not particularly limited. The number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42b may also be one. The number of cooling medium channel portions 62 arranged in one cooling medium connecting hole 42b may also be multiple other than three.

[0089] like Figure 6 to Figure 8 As shown in FIG. 1 , the first portion 72 of the rubber seal member R protrudes from the flat portion 76 in the above-mentioned protruding direction. The second portion 74 of the rubber seal member R protrudes from the protruding end surface Ta of the channel portion T disposed at the intersection 78 in the above-mentioned protruding direction. Figure 6 as well as Figure 8As shown, the first portion 72 and the second portion 74 extend continuously along the extending direction of the rubber sealing member R.

[0090] In addition, if Fig. 7A , Figure 7B , Figure 8 As shown, the protrusion height H1 of the first portion 72 of the plane portion 76 and the protrusion height H2 of the second portion 74 of the plane portion 76 are constant in the extending direction of the rubber seal member R. That is, the sum of the protrusion height H1 of the first portion 72 of the plane portion 76, the protrusion height H3 of the channel portion T of the plane portion 76, and the protrusion height H4 of the second portion 74 of the channel portion T from the protruding end surface Ta is the same or substantially the same.

[0091] like Figure 8 As shown, in the intersection 78, the side surfaces Tb on both sides of the width direction of the channel portion T are in contact with the rubber sealing member R. In the present embodiment, the side surfaces Tb on both sides of the width direction of the channel portion T are inclined toward each other as they approach the front end portion in the protruding direction. Therefore, the cross-sectional shape of the channel portion T along the partition thickness direction is a trapezoid. Moreover, the side surfaces Tb on both sides of the width direction of the channel portion T may also be along the partition thickness direction. That is, the cross-sectional shape of the channel portion T along the partition thickness direction may also be a square or a rectangle. Furthermore, the side surfaces Tb on both sides of the width direction of the channel portion T may also be curved.

[0092] A fuel cell stack 16 ( Figure 1 ) action. Figure 1 As shown, when the fuel cell stack 16 generates electricity, fuel gas is supplied to the fuel gas inlet passage 44a, oxidant gas is supplied to the oxidant gas inlet passage 40a, and coolant is supplied to the coolant inlet passage 42a.

[0093] like Figure 4 As shown in FIG. 1 , the oxidant gas is introduced from the oxidant gas inlet communication hole 40a into the oxidant gas flow path 52 via the communication path in the oxidant gas channel portion 54. The oxidant gas moves in the direction of arrow symbol B along the oxidant gas flow path 52 and is supplied to the cathode electrode 38 of the MEA 28 with a resin frame. Figure 5 As shown, the fuel gas is introduced from the fuel gas inlet passage 44a into the fuel gas flow path 56 via the communication path in the fuel gas channel portion 58. The fuel gas moves in the direction of arrow B along the fuel gas flow path 56 and is supplied to the anode electrode 36 of the resin framed MEA 28.

[0094] Therefore, in each resin-framed MEA 28 , the oxidant gas and the fuel gas are consumed by electrochemical reaction in the cathode electrode catalyst layer 38 a and the anode electrode catalyst layer 36 a , thereby generating electric power.

[0095] The oxidant gas (oxidant exhaust) that is not consumed in the electrochemical reaction flows from the oxidant gas flow path 52 to the oxidant gas outlet communication hole 40b via the communication path in the oxidant gas channel portion 54. The oxidant gas (oxidant exhaust) that flows into the oxidant gas outlet communication hole 40b flows in the direction of arrow symbol A in the oxidant gas outlet communication hole 40b and is discharged from the fuel cell stack 16. Similarly, the feed gas (fuel exhaust) that is not consumed in the electrochemical reaction flows from the fuel gas flow path 56 to the fuel gas outlet communication hole 44b via the communication path in the fuel gas channel portion 58. The fuel gas (fuel exhaust) that flows into the fuel gas outlet communication hole 44b flows in the direction of arrow symbol A in the fuel gas outlet communication hole 44b and is discharged from the fuel cell stack 16.

[0096] like Figure 3 As shown, the cooling medium is introduced into the cooling medium flow path 60 from the cooling medium inlet communication hole 42a via the communication path in the cooling medium channel portion 62. The cooling medium introduced into the cooling medium flow path 60 moves along the cooling medium flow path 60 in the direction of the arrow symbol B, and performs heat exchange with the MEA 28 with the resin frame. The cooling medium after the heat exchange flows into the cooling medium outlet communication hole 42b via the communication path in the cooling medium channel portion 62. The cooling medium flowing into the cooling medium outlet communication hole 42b flows in the cooling medium outlet communication hole 42b in the direction of the arrow symbol A and is discharged from the fuel cell stack 16.

[0097] In the separator 10 for the fuel cell according to the present embodiment, as described above, the rubber sealing member R and the channel portion T are formed of different members. The rubber sealing member R seals between the fluid flow path F and the fluid communication hole H. The channel portion T forms a communication path that connects the fluid flow path F and the fluid communication hole H. Therefore, for example, compared with a case where the rubber sealing member R and the channel portion T are continuously formed of the same member, it is possible to suppress the rubber sealing member R and the channel portion T from being elastically deformed integrally at the intersection 78 to which a compressive load is applied.

[0098] That is, the rubber sealing member R can be elastically deformed sufficiently due to the compressive load. Thus, the sealing performance between the fluid flow path F and the fluid communication hole H can be well ensured. On the other hand, in the channel portion T, even if a compressive load is applied, the shape of the communication path with a sufficient cross-sectional area formed inside can be maintained. Thus, the fluid can flow well between the fluid flow path F and the fluid communication hole H.

[0099] As described above, according to the separator 10 and the fuel cell stack 16 including the separator 10 according to the present embodiment, it is possible to ensure good sealing between the fluid flow path F and the fluid communication hole H. Also, the fluid can flow well in the communication path in the channel portion T.

[0100] In the fuel cell separator 10 according to the above-described embodiment, the protrusion height H1 of the first portion 72 of the flat portion 76 and the protrusion height H2 of the second portion 74 of the flat portion 76 are constant in the direction in which the rubber seal member R extends.

[0101] In this case, the linear pressure applied to the front end surface Ra of the rubber sealing member R due to the compressive load can be made uniform in the extending direction of the rubber sealing member R. As a result, it is easy to apply an appropriate amount of linear pressure to the entire rubber sealing member R, thereby further ensuring the sealing performance of the rubber sealing member R. The linear pressure here is the average value per unit length of the surface pressure applied to the front end surface Ra of the rubber sealing member R due to the above-mentioned compressive load in the extending direction of the rubber sealing member R.

[0102] Furthermore, the protrusion height H1 from the first portion 72 of the planar portion 76 may be different from the protrusion height H2 from the second portion 74 of the planar portion 76. For example, the protrusion height H2 from the second portion 74 of the planar portion 76 may be higher than the protrusion height H1 from the first portion 72 of the planar portion 76.

[0103] In the fuel cell separator 10 according to the above-described embodiment, a plurality of (two) rubber sealing members R are provided side by side in the separator surface direction as a set.

[0104] In this case, for example, in the fuel cell stack 16, even if the relative positions of the power generation cells 12 are deviated in the separator surface direction, it is easy to maintain the state in which any one of the plurality of rubber sealing members R is arranged in the stacking direction with any one of the plurality of rubber sealing members R of the adjacent separator 10. As a result, the sealing performance of the rubber sealing member R to the fluid flow path F and the fluid communication hole H can be further well ensured. In addition, by making the plurality of rubber sealing members R a group, it is possible to suppress excessive linear pressure applied to each rubber sealing member R. As a result, for example, the durability of the rubber sealing member R can be improved. Furthermore, the sealing performance between the fluid flow path F and the fluid communication hole H can be easily ensured.

[0105] Furthermore, in the above-mentioned embodiment, an example is described in which two rubber sealing members R are arranged side by side in the partition surface direction as a set (double layer). However, three or more rubber sealing members R may be arranged side by side in the partition surface direction as a set. Fig. 9AAs shown, the rubber sealing member R may also be composed of one piece (single layer).

[0106] In the intersection portion 78 of the fuel cell separator 10 according to the above-described embodiment, the side surfaces Tb rising from the flat surface portion 76 abut against the rubber seal member R at both ends of the channel portion T in the width direction.

[0107] The above-mentioned compressive load is applied in the stacking direction (the protruding direction of the channel portion T). Therefore, in the channel portion T to which the above-mentioned compressive load is applied, the protruding end surface Ta is directed toward the inner side of the connecting path along the stacking direction, and stress is easily generated in the direction of the side surface Tb toward the outside of the width direction of the connecting path. However, the rubber sealing member R is in contact with the side surface Tb of the channel portion T. Therefore, even if the above-mentioned stress occurs, the deformation of the channel portion T can be suppressed. Furthermore, the cross-sectional area of ​​the connecting path in the channel portion T can be maintained, so that the fluid can flow well in the connecting path.

[0108] Furthermore, the present invention is not limited to the above-described embodiment, and various structures can be obtained without departing from the gist of the present invention.

[0109] For example, in the fuel cell stack 16 according to the above-mentioned embodiment, the shape and size of the first rubber sealing member R1 are set to be the same or substantially the same as the shape and size of the second rubber sealing member R2, but the present invention is not particularly limited thereto. Fig. 9B As shown, the width of the first rubber sealing member R1 is set smaller than the width of the second rubber sealing member R2.

[0110] Moreover, in Fig. 9B In the embodiment, the first rubber sealing member R1 is composed of one (single layer). The second rubber sealing member R2 is composed of one (single layer). The width of the first rubber sealing member R1 is different from the width of the second rubber sealing member R2. However, the first rubber sealing member R1 may be composed of two (double layers) or more than three. The second rubber sealing member R2 may be composed of two (double layers) or more than three. The width of these first rubber sealing members R1 may be different from the width of the second rubber sealing member R2. Although not shown in the figure, the width of the first rubber sealing member R1 may be set smaller than the width of the second rubber sealing member R2.

[0111] Furthermore, for example, even when the width of the first rubber sealing member R1 and the width of the second rubber sealing member R2 are made the same in one separator 10 , the widths of the rubber sealing members R of separators 10 adjacent to each other in the stacking direction may be different.

[0112] That is, in the fuel cell stack 16, the rubber sealing members R provided on the plurality of separators 10 stacked in the stacking direction may be arranged side by side in the stacking direction. The rubber sealing members R adjacent to each other in the stacking direction may have different widths perpendicular to the extending direction of the rubber sealing members R.

[0113] In this case, for example, in the fuel cell stack 16, even if the relative positions of the power generation cells 12 are offset in the separator surface direction, the rubber seal members R of the adjacent separators 10 can be easily maintained in a state where the rubber seal members R sandwich the resin frame member 32 and abut against each other. As a result, it is easy to maintain a state where an appropriate linear pressure is applied to the front end surface Ra of each rubber seal member R. As a result, the sealing performance of the rubber seal member R to the fluid flow path F and the fluid communication hole H can be further well ensured.

Claims

1. A separator (10) for a fuel cell, which is stacked on an electrolyte membrane-electrode structure (30) and to which a compressive load in a stacking direction is applied, wherein the separator for a fuel cell comprises: A fluid flow path (F) for allowing any one of the oxidant gas, fuel gas, and cooling medium to flow in the direction of the separator surface; a fluid communication hole (H) which penetrates an outer region (64) arranged outside the fluid flow path along the partition surface direction in the stacking direction and allows the fluid to flow in the stacking direction; a rubber sealing member (R) for sealing between the fluid flow path and the fluid communication hole; as well as a channel portion (T) which is hollow and protrudes from a plane portion (76) provided in the outer region in the stacking direction, intersects with the rubber sealing member at an intersection portion (78) and extends, and forms a communication path inside thereof for connecting the fluid flow path with the fluid communication hole, The rubber sealing member is formed of a member different from the channel portion and has a first portion (72) and a second portion (74) extending continuously from each other. The first portion protrudes from the planar portion in the stacking direction, The second portion protrudes from a protruding end surface (Ta) of the channel portion disposed at the intersection toward the stacking direction. The separator is formed by a first bipolar plate (48) and a second bipolar plate (50) which are stacked in the stacking direction and bonded to each other. The channel portion includes: a first channel portion provided on the planar portion of the first bipolar plate and bulged to protrude toward one side in the stacking direction; as well as a second channel portion provided on the planar portion of the second bipolar plate and bulging so as to protrude toward the other side in the stacking direction; The communication path is formed by the first channel portion and the second channel portion, The rubber sealing member is further composed of a plurality of rubber sealing members that are arranged side by side and separated from each other in the partition surface direction, and there are gaps between the plurality of rubber sealing members through which the planar portion is exposed. The plurality of rubber sealing members each intersect the channel portion, and the channel portion is exposed in the gap.

2. The separator for a fuel cell according to claim 1, It is characterized in that A protrusion height (H1) of the first portion from the plane portion and a protrusion height (H2) of the second portion from the plane portion are constant in an extending direction of the rubber sealing member.

3. The separator for a fuel cell according to claim 1, It is characterized in that At the intersection, side surfaces (Tb) on both sides of the tunnel portion in the width direction are in contact with the rubber seal member.

4. A fuel cell stack (16) formed by stacking a plurality of separators for fuel cells according to any one of claims 1 to 3 and the electrolyte membrane-electrode structure in the stacking direction.

5. The fuel cell stack according to claim 4, It is characterized in that The rubber sealing members provided on the plurality of the separators stacked in the stacking direction are arranged side by side in the stacking direction. The rubber sealing members adjacent to each other in the stacking direction have different widths perpendicular to the extending direction of the rubber sealing members.

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