JP2012033325A - Fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell capable of ensuring reaction gas channels as well as gas sealability at reaction gas inlet and outlet parts, while suppressing the complication of processing process and an increase in size of the fuel cell.SOLUTION: The fuel cell comprises: a power generation module; first and second separators; a first interior channel formation member which forms between itself and the first separator an interior channel space for communicating a reaction gas channel used on the first separator side to an end on the first separator side of the power generation module; and a second interior channel formation member which forms between itself and the first separator an interior channel space for communicating a reaction gas channel used on the second separator side to an end on the second separator side of the power generation module. The end of the first interior channel formation member is in contact with a surface on the first separator side of a diffusion layer on the first separator side.

Description

  The present invention relates to a fuel cell.

  In general, a fuel cell has a stack structure in which a power generation module including a membrane electrode assembly having a structure in which an anode is provided on one surface of an electrolyte membrane and a cathode is provided on the other surface and separators are alternately stacked. Used. A fuel cell directly converts chemical energy of a substance into electrical energy by causing an electrochemical reaction using a reaction gas (fuel gas and oxidant gas) supplied to the membrane electrode assembly.

  The reaction gas supplied to the fuel cell is guided to the membrane electrode assembly through the manifold, and the reaction gas not used in the membrane electrode assembly is discharged to the manifold. The reaction gas introduction part from the manifold to the membrane electrode assembly and the part from the membrane electrode assembly to the manifold (hereinafter also referred to as “reaction gas lead-in / out part”) secure the reaction gas flow path and provide gas sealing properties. It is required to be compatible with

  A configuration of a reaction gas lead-in / out section formed by folding back a portion of a metal separator where an opening for a manifold is formed and providing a communication hole in the folded portion for communicating the manifold and the internal gas flow path space is known. (For example, refer to Patent Document 1).

JP 2009-93850 A

  In the above-described conventional technology, a sealing material such as an adhesive or a thermoplastic resin is disposed at the end position along the surface direction of the power generation module in the internal gas flow path space, and the leakage of the reaction gas between the two electrodes is prevented by the sealing material. Is done. Therefore, if the sealing material is insufficient, the gas sealing performance may not be ensured, and the reaction gas may leak. On the other hand, if the sealing material is excessive, the excess sealing material is removed from the internal gas flow path space. There is a risk that the flow path may be blocked and the pressure loss may increase or vary.

  The present invention has been made in order to solve the above-described problems, and secures a reaction gas flow path and a gas seal in a reaction gas lead-in / out section while suppressing the complexity of the processing steps and the increase in the size of the fuel cell. It aims at providing the fuel cell which achieved coexistence with ensuring of property.

  In order to solve at least a part of the above problems, the present invention can be realized as the following forms or application examples.

Application Example 1 A fuel cell,
A power generation module having a membrane electrode assembly including an electrolyte membrane and electrode layers disposed on both surfaces of the electrolyte membrane, and a pair of diffusion layers stacked so as to sandwich the membrane electrode assembly layer;
The first and second separators are formed by processing a metal plate and are arranged so as to sandwich the power generation module, and are located outside a position facing the power generation module along the surface direction of the power generation module. First and second separators having openings constituting a plurality of reaction gas flow paths substantially perpendicular to the surface direction at positions;
The reaction gas flow path for the reaction gas used in the electrode layer on the first separator side between the first separator and the surface direction on the first separator side of the power generation module. A first internal flow path forming member that forms a first internal flow path space that communicates with the end portion;
The reaction gas flow path for the reaction gas used in the electrode layer on the second separator side between the first separator and the surface direction on the second separator side of the power generation module. A second internal flow path forming member that forms a second internal flow path space that communicates with the end,
A seal member that seals between the first internal flow path forming member and the second internal flow path forming member and the second separator;
An inner end portion of the first internal flow path forming member along the surface direction is in contact with the surface of the diffusion layer on the first separator side on the first separator side.

  In this fuel cell, the first internal flow path forming member and the first separator of the power generation module and the reactive gas flow path for the reactive gas used in the electrode layer on the first separator side between the first separator and the first separator. A first internal channel space that communicates with an end of the separator on the side of the separator is formed, and the second internal channel forming member is used in the electrode layer on the second separator side between the first separator and the first separator. A second internal flow path space is formed that communicates the reactive gas flow path for the reactive gas and the end of the power generation module on the second separator side. Further, the seal member seals between the first internal flow path forming member and the second internal flow path forming member and the second separator. Moreover, the inner side edge part along the surface direction of the 1st internal flow path formation member is contacting the surface by the side of the 1st separator of the diffusion layer by the side of the 1st separator. For this reason, in this fuel cell, the contact portion between the first internal flow path forming member and the diffusion layer on the first separator side suppresses the leakage of the reaction gas and improves the gas sealing performance. The entrance of the seal member into the flow path space is suppressed, and the first internal flow path space can be prevented from being blocked and the pressure loss can be increased. Therefore, in this fuel cell, it is possible to achieve both the securing of the reaction gas flow path and the securing of the gas sealing property in the reaction gas lead-in / out section while suppressing the complexity of the processing process and the increase in the size of the fuel cell. it can.

[Application Example 2] The fuel cell according to Application Example 1,
In the first internal flow path forming member and the second internal flow path forming member, at least a part of the metal plate at a position where the opening of the first separator is formed is on the power generation module side of the opening. Is formed by a folded portion formed by folding back to the power generation module side as a folding line,
The folded portion has a communication hole that communicates the reaction gas flow path with the first internal flow path space and the second internal flow path space.

  In this fuel cell, as compared with the case where the first and second internal flow path spaces are secured by separate parts while suppressing a short circuit by suppressing the folded portion from moving to the second separator side. In addition, it is possible to reduce the number of parts, simplify the machining process, and reduce the cost.

Application Example 3 A fuel cell,
A membrane electrode assembly including an electrolyte membrane and electrode layers disposed on both sides of the electrolyte membrane; a pair of diffusion layers stacked so as to sandwich the membrane electrode assembly layer; and each of the pair of diffusion layers A power generation module having a pair of porous flow path layers stacked on the outside;
The first and second separators are formed by processing a metal plate and are arranged so as to sandwich the power generation module, and are located outside a position facing the power generation module along the surface direction of the power generation module. First and second separators having openings constituting a plurality of reaction gas flow paths substantially perpendicular to the surface direction at positions;
The reaction gas flow path for the reaction gas used in the electrode layer on the first separator side between the first separator and the surface direction on the first separator side of the power generation module. A first internal flow path forming member that forms a first internal flow path space that communicates with the end portion;
The reaction gas flow path for the reaction gas used in the electrode layer on the second separator side between the first separator and the surface direction on the second separator side of the power generation module. A second internal flow path forming member that forms a second internal flow path space that communicates with the end,
A seal member that seals between the first internal flow path forming member and the second internal flow path forming member and the second separator;
The inner end along the surface direction of the first internal flow path forming member includes the surface on the first separator side of the diffusion layer on the first separator side and the surface on the first separator side. A fuel cell in contact with one of the surface of the porous body flow path layer on the second separator side.

  In this fuel cell, the first internal flow path forming member and the first separator of the power generation module and the reactive gas flow path for the reactive gas used in the electrode layer on the first separator side between the first separator and the first separator. A first internal channel space that communicates with an end of the separator on the side of the separator is formed, and the second internal channel forming member is used in the electrode layer on the second separator side between the first separator and the first separator. A second internal flow path space is formed that communicates the reactive gas flow path for the reactive gas and the end of the power generation module on the second separator side. Further, the seal member seals between the first internal flow path forming member and the second internal flow path forming member and the second separator. Further, the inner end portion along the surface direction of the first internal flow path forming member includes the first separator-side surface of the first separator-side diffusion layer and the first separator-side porous flow path layer. Of the second separator and the surface on the second separator side. Therefore, in this fuel cell, in order to ensure gas sealing properties by the contact portion between the first internal flow path forming member and the first separator side diffusion layer or the first separator side porous flow path layer. Even if the sealing member is filled so that there is no shortage, the sealing member is prevented from entering the first internal flow path space, so that the complexity of the processing process and the increase in the size of the fuel cell are suppressed. On the other hand, it is possible to achieve both the securing of the reaction gas flow path and the securing of the gas sealing performance in the reaction gas lead-in / out section.

[Application Example 4] The fuel cell according to Application Example 3,
In the first internal flow path forming member and the second internal flow path forming member, at least a part of the metal plate at a position where the opening of the first separator is formed is on the power generation module side of the opening. Is formed by a folded portion formed by folding back to the power generation module side as a folding line,
The folded portion has a communication hole that communicates the reaction gas flow path with the first internal flow path space and the second internal flow path space.

  In this fuel cell, the number of parts, the processing process can be simplified, and the cost can be reduced as compared with the case where the first and second internal flow path spaces are secured by separate parts.

[Application Example 5] The fuel cell according to Application Example 3 or Application Example 4,
The inner end along the surface direction of the first internal flow path forming member is in contact with the surface on the second separator side of the porous flow path layer on the first separator side,
The porous body flow path layer on the first separator side overlaps the first internal flow path forming member along the stacking direction from a position corresponding to the outer end portion along the surface direction of the diffusion layer. A fuel cell in which a portion up to a position corresponding to an inner end portion along the surface direction of the portion is subjected to sealing treatment.

  In this fuel cell, it is possible to improve the gas sealing performance in the portion of the porous channel layer on the first separator side that overlaps the first internal channel forming member along the stacking direction, and the sealing member is the first. Of the separator-side porous body flow passage layer is prevented from entering the first internal flow passage space, so that the reaction gas flow passage and the gas sealing performance at the reaction gas lead-in / out portion are secured. A balance can be achieved more reliably.

  The present invention can be realized in various modes, and can be realized in the form of, for example, a fuel cell, a separator for a fuel cell, a fuel cell system, a method for manufacturing these devices or systems, and the like. .

1 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 according to a first embodiment of the present invention. 3 is an explanatory diagram showing a planar configuration of a single cell 140 of the fuel cell 100. FIG. It is explanatory drawing which shows the planar structure of the single cell 140 in detail. 3 is an explanatory diagram showing a cross-sectional configuration of a single cell 140. FIG. 3 is an explanatory diagram showing a cross-sectional configuration of a single cell 140. FIG. 4 is a perspective view showing a configuration in the vicinity of an opening 321 of a cathode side separator 320. FIG. It is a flowchart which shows the manufacturing process of the single cell 140 in 1st Example. 5 is a flowchart showing a forming process of a cathode side separator 320. FIG. 6 is an explanatory view showing a state of the cathode side separator 320 at each stage in the molding process of the cathode side separator 320. It is explanatory drawing which shows the cross-sectional structure of the single cell 140a which comprises the fuel cell in 2nd Example.

  Next, embodiments of the present invention will be described based on examples.

A. First embodiment:
FIG. 1 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 according to a first embodiment of the present invention. The fuel cell system 10 includes a fuel cell 100. In the fuel cell 100, an end plate 110, an insulating plate 120, a current collecting plate 130, a plurality of single cells 140, a current collecting plate 130, an insulating plate 120, and an end plate 110 are stacked in this order. Have a stack structure.

  Hydrogen as fuel gas is supplied to the fuel cell 100 from a hydrogen tank 50 that stores high-pressure hydrogen via a shut valve 51, a regulator 52, and a pipe 53. The fuel gas (anode off gas) that has not been used in the fuel cell 100 is discharged to the outside of the fuel cell 100 through the discharge pipe 63. The fuel cell system 10 may have a recirculation mechanism that recirculates the anode off gas to the pipe 53 side. The fuel cell 100 is also supplied with air as an oxidant gas via an air pump 60 and a pipe 61. The oxidant gas (cathode off-gas) that has not been used in the fuel cell 100 is discharged to the outside of the fuel cell 100 via the discharge pipe 54. The fuel gas and the oxidant gas are also called reaction gas.

  Further, the cooling medium cooled by the radiator 70 is supplied to the fuel cell 100 via the water pump 71 and the pipe 72 in order to cool the fuel cell 100. The cooling medium discharged from the fuel cell 100 is circulated to the radiator 70 via the pipe 73. As the cooling medium, for example, water, an antifreeze such as ethylene glycol, air, or the like is used.

  FIG. 2 is an explanatory diagram showing a planar configuration of the single cell 140 of the fuel cell 100. As will be described later, the unit cell 140 has a configuration in which a power generation module including a membrane electrode assembly (also referred to as MEA) in which an anode and a cathode are disposed on both surfaces of an electrolyte membrane is sandwiched between a pair of separators. Yes.

  Inside the fuel cell 100, as shown in FIG. 2, a fuel gas supply manifold 162 that distributes hydrogen as fuel gas supplied to the fuel cell 100 to each single cell 140, and an oxidation supplied to the fuel cell 100 An oxidant gas supply manifold 152 that distributes air as an agent gas to each unit cell 140, a fuel gas discharge manifold 164 that collects fuel gas that has not been used in each unit cell 140, and discharges the fuel gas to the outside of the fuel cell 100, An oxidant gas discharge manifold 154 that collects oxidant gas that has not been used in each single cell 140 and discharges it to the outside of the fuel cell 100 is formed. Each of the manifolds is a reaction gas passage having a shape extending in the stacking direction of the fuel cells 100 (that is, a direction substantially perpendicular to the surface direction of the power generation module). Further inside the fuel cell 100, a cooling medium supply manifold 172 that distributes the cooling medium to the single cells 140, and a cooling medium discharge that collects the cooling media discharged from each single cell 140 and discharges them to the outside of the fuel cell 100. A manifold 174 is formed.

  FIG. 3 is an explanatory diagram showing the planar configuration of the single cell 140 in more detail. 3A shows an enlarged plan view of a portion (X1 portion in FIG. 2) in the vicinity of the fuel gas supply manifold 162 in the single cell 140, and FIG. The plane structure of the part (X2 part of FIG. 2) vicinity of the oxidizing gas supply manifold 152 is expanded and shown. 4 and 5 are explanatory diagrams showing a cross-sectional configuration of the single cell 140. FIG. 4A shows the A1-A1 cross section of FIG. 3A, FIG. 4B shows the B1-B1 cross section of FIG. 3A, and FIG. Shows a cross section taken along line C1-C1 in FIG. 3B, and FIG. 5B shows a cross section taken along line D1-D1 in FIG.

  As shown in FIGS. 4 and 5, the single cell 140 has a power generation module 200 and a pair of separators (cathode side separator 320 and anode side separator 310) that sandwich the power generation module 200. The power generation module 200 includes a cathode side porous body flow path layer 230, a cathode side diffusion layer 217, a membrane electrode assembly 210, an anode side diffusion layer 216, and an anode side porous body flow path layer 220 in this order. It has a stacked configuration. The membrane electrode assembly 210 includes an electrolyte membrane 212, a cathode 215 disposed (applied) on one side of the electrolyte membrane 212, and an anode 214 disposed (coated) on the other side of the electrolyte membrane 212. Has been. In FIG. 2, the position of the power generation module 200 in the plane of the single cell 140 is indicated by hatching.

  The electrolyte membrane 212 is a solid polymer membrane formed of a fluorine resin material or a hydrocarbon resin material, and has good proton conductivity in a wet state. The cathode 215 and the anode 214 include, for example, platinum as a catalyst or an alloy made of platinum and another metal. The cathode side diffusion layer 217 and the anode side diffusion layer 216 are made of, for example, carbon cloth woven with yarns made of carbon fibers, carbon paper, or carbon felt. The cathode-side porous flow path layer 230 and the anode-side porous flow path layer 220 are formed of a porous material having gas diffusibility and conductivity such as a metal porous body (for example, expanded metal). Since the cathode-side porous channel layer 230 and the anode-side porous channel layer 220 have a higher porosity than the cathode-side diffusion layer 217 and the anode-side diffusion layer 216, the flow resistance of the gas inside is low, and the reaction gas Functions as a flow path.

  In the following description, the direction in which the layers of the power generation module 200 are stacked is simply referred to as “stacking direction”, and the surface direction of the power generation module 200 (that is, a direction substantially perpendicular to the stacking direction) is simply referred to as “plane direction”. Shall be called. Of the surface directions, the direction parallel to the outer periphery of each layer of the power generation module 200 closest to the fuel gas supply manifold 162 and the oxidant gas supply manifold 152 is called the Y direction, and the surface direction substantially perpendicular to the Y direction is X. It shall be called a direction (refer FIG. 3 thru | or FIG. 5).

  As shown in FIGS. 4 and 5, the electrolyte membrane 212, the anode side diffusion layer 216, and the anode side porous channel layer 220 are arranged in the X direction at positions facing the fuel gas supply manifold 162 and the oxidant gas supply manifold 152. The length along the line is longer than the lengths of other layers (the anode 214, the cathode 215, the cathode side diffusion layer 217, and the cathode side porous body flow path layer 230) constituting the power generation module 200. That is, when the power generation module 200 is viewed from the stacking direction of the fuel cell 100, the electrolyte membrane 212, the anode-side diffusion layer 216, and the anode-side porous channel layer 220 protrude from the other layers in the X direction. 3A and 3B, the positions of the electrolyte membrane 212, the anode 214, and the cathode 215 in the plane of the single cell 140 are indicated by hatching.

  The cathode side separator 320 and the anode side separator 310 are formed by processing a metal plate. As shown in FIGS. 4 (a) and 4 (b), the cathode-side separator 320 is formed with an opening 321 constituting a fuel gas supply manifold 162, and FIGS. 5 (a) and 5 (b). ), An opening 323 constituting the oxidant gas supply manifold 152 is formed.

  FIG. 6 is a perspective view showing a configuration near the opening 321 of the cathode separator 320. As shown in FIGS. 4 and 6, a folded portion 322 is formed at a position adjacent to the opening 321 for constituting the fuel gas supply manifold 162 of the cathode side separator 320. As will be described in detail later, the folded portion 322 has at least a part of the portion where the opening 321 is formed in the metal plate as the material of the cathode-side separator 320. As described above, it is formed by folding back in the inner direction (direction toward the anode separator 310) along the stacking direction of the single cells 140 and in the inner direction (direction toward the power generation module 200) along the X direction. .

  As shown in FIGS. 4A and 4B, the folded portion 322 includes a vertical portion that is substantially perpendicular to the plane direction (substantially parallel to the stacking direction) and a parallel portion that is substantially parallel to the plane direction. ing. The position along the stacking direction of the parallel portion of the folded portion 322 is a position closer to the cathode side than the position of the electrolyte membrane 212. An internal channel space 350 is formed between the parallel portion of the folded portion 322 and the portion of the cathode separator 320 facing the parallel portion of the folded portion 322 along the stacking direction. The internal flow path space 350 corresponds to the second internal flow path space in the present invention, and the folded portion 322 corresponds to the second internal flow path forming member that forms the second internal flow path space in the present invention. . A plurality of communication holes 326 for communicating the fuel gas supply manifold 162 and the internal flow space 350 are formed in the vertical portion of the folded portion 322. The plurality of communication holes 326 are arranged side by side at predetermined intervals along the Y direction (see FIG. 6).

  A shape protruding in the direction from the cathode separator 320 toward the anode separator 310 (that is, a shape protruding into the internal channel space 350) is located at the position of the cathode separator 320 facing the parallel portion of the folded portion 322 along the stacking direction. A plurality of convex portions 324 are formed. The plurality of convex portions 324 are arranged side by side at a predetermined interval along the Y direction so that positions along the Y direction do not overlap with the communication holes 326. Each convex portion 324 has a substantially rectangular plane extending in the X direction. The position along the stacking direction of the portion substantially parallel to the surface direction of each convex portion 324 is a position adjacent to the parallel portion of the folded portion 322.

  Similarly, as shown in FIGS. 5A and 5B, a folded portion 325 is formed at a position adjacent to the opening 323 for constituting the oxidant gas supply manifold 152 in the cathode side separator 320. ing. The folded portion 325 is formed by stacking the single cells 140 with at least a part of the portion of the metal plate as the material of the cathode-side separator 320 at the position where the opening 323 is formed, with the side of the opening 323 on the power generation module 200 side being a folding line. It is formed by folding back in the inner direction along the direction and in the inner direction along the X direction. The folded portion 325 includes a vertical portion that is substantially perpendicular to the surface direction and a parallel portion that is substantially parallel to the surface direction. The position along the stacking direction of the parallel part of the folded part 325 is a position closer to the cathode side than the position of the electrolyte membrane 212, similarly to the folded part 322. An internal channel space 360 is formed between the parallel part of the folded part 325 and the part of the cathode separator 320 facing the parallel part of the folded part 325 along the stacking direction. The internal flow path space 360 corresponds to the first internal flow path space in the present invention, and the folded portion 325 corresponds to the first internal flow path forming member that forms the first internal flow path space in the present invention. . A plurality of communication holes 326 for communicating the oxidant gas supply manifold 152 and the internal flow path space 360 are formed in the vertical portion of the folded portion 325. The plurality of communication holes 326 are arranged side by side at predetermined intervals along the Y direction.

  A shape protruding in the direction from the cathode side separator 320 toward the anode side separator 310 (that is, a shape protruding into the internal channel space 360) is located at the position of the cathode side separator 320 facing the parallel part of the folded portion 325 along the stacking direction. A plurality of convex portions 324 are formed. The plurality of convex portions 324 are arranged side by side at a predetermined interval along the Y direction so that positions along the Y direction do not overlap with the communication holes 326. Each convex portion 324 has a substantially rectangular plane extending in the X direction. The position along the stacking direction of the portion substantially parallel to the surface direction of each convex portion 324 is a position adjacent to the parallel portion of the folded portion 325.

  In the following description, the folded portion 322 adjacent to the opening 321 for constituting the fuel gas supply manifold 162 in the cathode side separator 320 is also referred to as the fuel gas side folded portion 322, and the oxidant gas supply in the cathode side separator 320 is referred to. The folded portion 325 adjacent to the opening 323 for configuring the manifold 152 is also referred to as an oxidizing gas side folded portion 325.

  As shown in FIGS. 4A and 4B, the length along the X direction of the parallel portion of the fuel gas side folded portion 322 is such that it does not overlap the electrolyte membrane 212 along the stacking direction. It has become. In contrast, as shown in FIGS. 5A and 5B, the length along the X direction of the parallel portion of the oxidant gas side folded portion 325 is the same as that of the electrolyte membrane 212 along the stacking direction. The length is overlapping. That is, the length along the X direction of the parallel portion of the fuel gas side folded portion 322 is shorter than the length along the X direction of the parallel portion of the oxidant gas side folded portion 325. 3A and 3B, the positions of the parallel portion of the fuel gas side folded portion 322 and the parallel portion of the oxidant gas side folded portion 325 in the plane of the unit cell 140 are indicated by hatching.

  In addition, the cathode-side separator 320 has a convex portion 327 that protrudes in a direction from the cathode-side separator 320 toward the anode-side separator 310 at a position facing the protruding portion of the electrolyte membrane 212 (FIG. 4A). ) And (b)). The position along the stacking direction of the portion substantially parallel to the surface direction of the convex portion 327 is substantially the same as the parallel portion of the fuel gas side folded portion 322. A filler 430 is filled on the outer side of the convex portion 327 along the stacking direction. In addition, the convex part 327 is not formed in the position facing the oxidizing gas side folding | returning part 325 (refer Fig.5 (a) and (b)).

  Further, the cathode side separator 320 has a position surrounding three sides other than the side where the fuel gas side folded part 322 of the opening 321 is formed, and other than the side where the oxidant gas side folded part 325 of the opening 323 is formed. A convex portion 329 that protrudes in the direction from the cathode side separator 320 to the anode side separator 310 is formed at a position surrounding the three sides (see FIGS. 3 to 5). The position along the stacking direction of the portion substantially parallel to the surface direction of the convex portion 329 is substantially the same as the parallel portion of the folded portions 322 and 325.

  A plurality of dimples 319 are formed at positions facing the membrane electrode assembly 210 in the cathode side separator 320. When the plurality of unit cells 140 are stacked, the outermost surface in the stacking direction of the dimples 319 is in contact with the surface of the anode-side separator 310 of another unit cell 140 adjacent in the stacking direction. Thus, between the two single cells 140 (that is, between the cathode side separator 320 and the anode side separator 310 adjacent to the cathode side separator 320 without sandwiching the membrane electrode assembly 210) along the surface direction. A continuous space is formed. This space communicates with the cooling medium supply manifold 172 and the cooling medium discharge manifold 174 shown in FIG. 2, and is used as a flow path for the cooling medium.

  As shown in FIGS. 4 and 5, the anode side separator 310 is provided with an opening 311 that constitutes a fuel gas supply manifold 162 and an oxidant gas supply manifold 152, similarly to the cathode side separator 320. An opening 313 is formed. Further, on the anode side separator 310, a convex portion 312 having a convex shape in the direction from the anode side separator 310 toward the cathode side separator 320 is provided on the outer side in the plane direction from the position facing the fuel gas side folded portion 322 of the cathode side separator 320. Is formed. The position along the stacking direction of the portion substantially parallel to the surface direction of the convex portion 312 is such that a slight space for sealing is provided between the fuel gas side folded portion 322 and the portion substantially parallel to the surface direction of the convex portion 329. It is a position to be secured. Further, a convex portion 315 having a convex shape in a direction from the anode side separator 310 toward the cathode side separator 320 outward from the position facing the oxidant gas side folded portion 325 of the cathode side separator 320 in the anode side separator 310. Is formed. The position along the stacking direction of the portion substantially parallel to the surface direction of the convex portion 315 is a slight space for sealing between the oxidant gas side folded portion 325 and the portion substantially parallel to the surface direction of the convex portion 329. It is a position where is secured.

  Note that the folded portions 322 and 325 are not formed in the anode side separator 310 unlike the cathode side separator 320. The cathode side separator 320 in the first embodiment corresponds to the first separator in the present invention, and the anode side separator 310 in the first embodiment corresponds to the second separator in the present invention.

  As shown in FIGS. 4A and 4B, a gap between the parallel portion of the fuel gas side folded portion 322 of the cathode side separator 320 and the convex portion 312 of the anode side separator 310 (R2 portion in the figure) is a seal. Sealed by a material 420. Further, the space between the convex portion 327 of the cathode separator 320 and the electrolyte membrane 212 (R1 portion in the figure) is sealed with a sealing material 410. Further, as shown in FIGS. 5A and 5B, between the parallel portion of the oxidant gas side folded portion 325 of the cathode side separator 320 and the convex portion 315 of the anode side separator 310, and on the oxidant gas side A space between the parallel portion of the folded portion 325 and the electrolyte membrane 212 (R3 portion in the figure) is sealed with a sealing material 440. Further, the convex portion 329 of the cathode side separator 320 and the convex portions 312 and 315 of the anode side separator 310 are sealed with a sealing material 450. Each sealing material exhibits a gas sealing function and a short-circuit prevention function at the sealing location. As the sealing material, for example, an adhesive or a thermoplastic resin is used.

  3 to 5 show the configuration in the vicinity of the fuel gas supply manifold 162 and the oxidant gas supply manifold 152 in the single cell 140, but the configurations in the vicinity of the fuel gas discharge manifold 164 and the oxidant gas discharge manifold 154 are the same. is there. That is, an opening constituting the fuel gas discharge manifold 164 is formed near the fuel gas discharge manifold 164 in the single cell 140, and a part of the metal plate is folded back toward the power generation module 200 next to the opening. A folded portion 322 is formed. The folded portion 322 is formed with a communication hole that communicates the internal flow path space formed between the folded portion 322 and the cathode separator 320 and the fuel gas discharge manifold 164. Further, an opening constituting the oxidant gas discharge manifold 154 is formed near the oxidant gas discharge manifold 154 in the single cell 140, and a part of the metal plate is directed in the direction of the power generation module 200 next to the opening. A folded portion 325 that is folded is formed. The folded portion 325 is formed with a communication hole that communicates the internal flow path space formed between the folded portion 325 and the cathode-side separator 320 and the oxidant gas discharge manifold 154.

  As shown in FIGS. 4 and 5, the single cell 140 has a seal line that surrounds the power generation module 200 and the manifold openings shown in FIGS. 2 and 3 in the surface direction when a plurality of single cells 140 are stacked. In order to form SL, a gasket 500 is arranged. The gasket 500 is formed by injection molding. The gasket 500 has a convex portion 502. The convex portion 502 of the gasket 500 arranged in a single cell 140 is in close contact with the surfaces of the convex portions 312 and 315 of the anode separator 310 of another adjacent single cell 140 when the plurality of single cells 140 are stacked. To form a seal line SL. The arrangement of the gasket 500 and the convex portion 502 in the plane of the single cell 140 is such that the seal line SL shown in FIGS. 2 and 3 is formed. In the cross section shown in FIGS. The arrangement overlaps the portion 324 and the convex portion 329.

  As shown by arrows in FIGS. 4A and 4B, hydrogen as fuel gas supplied to the fuel gas supply manifold 162 is guided to the internal flow path space 350 through the communication hole 326. The internal flow path space 350 communicates with an end portion along the surface direction on the anode side of the power generation module 200. Therefore, the fuel gas guided to the internal flow path space 350 reaches the end of the power generation module 200 and enters the anode-side porous flow path layer 220 having the smallest internal flow path resistance. Thereafter, the fuel gas is supplied to the anode side diffusion layer 216 and the anode 214 while diffusing in the anode side porous body flow path layer 220. The fuel gas that has not been used in the power generation module 200 is discharged to the fuel gas discharge manifold 164 through an internal passage space (not shown) formed on the fuel gas discharge manifold 164 side.

  5A and 5B, the air as the oxidant gas supplied to the oxidant gas supply manifold 152 is guided to the internal flow path space 360 through the communication hole 326. . The internal flow path space 360 communicates with an end portion along the surface direction on the cathode side of the power generation module 200. Therefore, the oxidant gas guided to the internal flow path space 360 reaches the end of the power generation module 200 and enters the cathode-side porous flow path layer 230 having the smallest internal flow path resistance. Thereafter, the oxidant gas is supplied to the cathode side diffusion layer 217 and the cathode 215 while diffusing in the cathode side porous channel layer 230. The oxidant gas that has not been used in the power generation module 200 is discharged to the oxidant gas discharge manifold 154 through an internal channel space (not shown) formed on the oxidant gas discharge manifold 154 side.

  FIG. 7 is a flowchart showing manufacturing steps of the single cell 140 in the first embodiment. In step S110 of the manufacturing process of the single cell 140, the cathode-side separator 320 is formed. FIG. 8 is a flowchart showing a forming process of the cathode-side separator 320. FIG. 9 is an explanatory view showing the state of the cathode separator 320 at each stage in the molding process of the cathode separator 320. FIG. 9 shows the state of the portion near the opening 321 constituting the fuel gas supply manifold 162 of the cathode side separator 320, but the state of the portion near the opening 323 constituting the oxidant gas supply manifold 152 is the same. is there.

  In step S <b> 210 of the forming process of the cathode-side separator 320, the metal plate as the material of the cathode-side separator 320 is subjected to press forming to form the convex portion 324. FIG. 9A shows a state in which the metal plate as the material of the cathode side separator 320 is pressed by the press machine P, and the convex portion 324 is formed. In addition, the part in which the convex part 324 in a metal plate is not formed becomes the internal flow path space 350 (or internal flow path space 360). FIG. 9B shows a state in which the convex portion 324 is formed at a position on the inner side in the surface direction (on the power generation module 200 side) from the position where the opening 321 in the metal plate is formed. In this press molding process, a convex portion 327 and a convex portion 329 are formed in addition to the convex portion 324.

  In step S <b> 220 of the forming process of the cathode-side separator 320, the metal plate as the material of the cathode-side separator 320 is drilled to form the communication hole 326. FIG. 9C shows a state where the communication hole 326 is formed in the metal plate. The communication hole 326 is formed so as to be arranged in the vicinity of the fold line of the opening 321 (or the opening 323) along the X direction and so that the position along the Y direction does not overlap the convex portion 324.

  In step S230 of the forming process of the cathode side separator 320, the metal plate as the material of the cathode side separator 320 is bent to form the fuel gas side folded portion 322 and the oxidant gas side folded portion 325. FIG. 9D shows a state in which the opening 321 is formed in the metal plate and a part of the position where the opening 321 is formed is bent. As a result, the cathode-side separator 320 is formed with an opening 321 constituting the fuel gas supply manifold 162 and an opening 323 constituting the oxidant gas supply manifold 152, and the fuel gas side folded portion 322 and the oxidant gas side folded. A portion 325 is formed.

  In step S120 of the manufacturing process (FIG. 7) of the single cell 140, the anode-side separator 310 is molded. In the formation of the anode-side separator 310, press forming is performed on a metal plate as a material, and openings 311 and 313 and convex portions 312 and 315 are formed. In step S <b> 130, a sealing material is disposed on the cathode side separator 320. The sealing material is disposed at the positions of the sealing materials 410, 420, 440, and 450 described above. In step S140, the layers constituting the power generation module 200 are stacked on the cathode side separator 320, and the anode side separator 310 is further stacked. In step S150, bonding by thermocompression bonding is performed in a stacked state, and the manufacture of the single cell 140 is completed.

  Here, as shown in FIGS. 5A and 5B, in the fuel cell 100 of the first embodiment, the end of the cathode side diffusion layer 217 is located at a position facing the oxidant gas supply manifold 152. An inner end portion (a portion indicated by OL in the drawing) along the surface direction of the oxidant gas side folded portion 325 protrudes outward from the cathode side porous body flow passage layer 230 in the X direction. It is in contact with the surface on the cathode-side separator 320 side (surface on the outer side in the stacking direction). That is, the oxidant gas side folded portion 325 and the cathode side diffusion layer 217 overlap along the stacking direction. Although not shown, similarly, at the position facing the oxidant gas discharge manifold 154, the end of the cathode side diffusion layer 217 protrudes outward in the X direction from the cathode side porous channel layer 230 in the same manner. The inner end along the surface direction of the gas-side folded portion 325 is in contact with the surface of the cathode-side diffusion layer 217 on the cathode-side separator 320 side.

  Thus, in the fuel cell 100 of the first embodiment, the inner end portion along the surface direction of the oxidant gas side folded portion 325 is in contact with the surface of the cathode side diffusion layer 217 on the cathode side separator 320 side. In addition, the overlap of the oxidant gas side folded portion 325 and the cathode side diffusion layer 217 prevents air from leaking to the anode side, and can ensure gas sealing performance. In particular, the oxidant gas side folded portion 325 formed by bending is subjected to a force in the direction in which the end thereof approaches the anode side separator 310 side along the stacking direction due to the spring back, and thus the oxidant gas side The end of the folded portion 325 is pressed against the surface of the cathode side diffusion layer 217 on the cathode separator 320 side. Therefore, in the fuel cell 100 of the first embodiment, good gas sealability can be ensured by the overlap portion between the oxidant gas side folded portion 325 and the cathode side diffusion layer 217. Further, in the fuel cell 100 of the first embodiment, the sealing material between the oxidant gas side folded portion 325 and the anode side separator 310 is formed by the overlap portion between the oxidant gas side folded portion 325 and the cathode side diffusion layer 217. Since it is suppressed that 440 enters the inside of internal channel space 360, obstruction | occlusion of internal channel space 360 and the increase in pressure loss by the approach of sealing material 440 can be controlled. Further, in the fuel cell 100 of the first embodiment, even if a force due to springback acts on the oxidant gas side folded portion 325, the oxidant gas side folded portion 325 becomes the anode side separator due to the presence of the cathode side diffusion layer 217. Since access to 310 is limited, a short circuit due to contact between the cathode-side separator 320 and the anode-side separator 310 can be reliably suppressed.

  As described above, in the fuel cell 100 according to the first embodiment, the cathode-side separator 320 is formed with the opening 321 constituting the fuel gas supply manifold 162 and the opening 323 constituting the oxidant gas supply manifold 152. An opening 311 constituting the fuel gas supply manifold 162 and an opening 313 constituting the oxidant gas supply manifold 152 are formed in the anode side separator 310. In addition, internal flow path spaces 350 and 360 communicating with the ends of the power generation module 200 are formed between the folded portion 322 and the folded portion 325 and the cathode separator 320. A space between each folded portion and the anode side separator 310 is sealed with a sealing material. Therefore, in the fuel cell 100 of the first embodiment, it is possible to achieve both the securing of the gas flow path and the securing of the gas sealing property in the reaction gas lead-in / out section, and both the cathode-side separator 320 and the anode-side separator 310 can be achieved. Compared with the case where the internal flow space for the reaction gas is formed, the complexity of the processing steps and the increase in the size of the fuel cell can be suppressed. In particular, in the fuel cell 100 of the first embodiment, the inner end portion along the surface direction of the oxidant gas side folded portion 325 is in contact with the surface of the cathode side diffusion layer 217 on the cathode side separator 320 side. The overlap portion between the agent gas side folded portion 325 and the cathode side diffusion layer 217 prevents air from leaking to the anode side, thereby improving the gas sealing performance and improving the sealing material 440 to the internal flow path space 360. The entry is suppressed, and the blockage of the internal flow path space 360 and an increase in pressure loss can be suppressed. Therefore, in the fuel cell 100 of the first embodiment, both the securing of the reaction gas flow path and the securing of the gas sealing property in the reaction gas lead-in / out portion are suppressed while suppressing the complexity of the processing process and the increase in the size of the fuel cell. Can be achieved.

  Further, in the fuel cell 100 of the first embodiment, the fuel gas side folded portion 322 as an internal flow path forming member that secures the internal flow path space 350 is formed, and the opening 321 in the metal plate as the material of the cathode side separator 320 is formed. At least a part of the portion of the position to be formed is formed by folding back to the power generation module 200 side with the side of the opening 321 on the power generation module 200 side as a fold line. Further, the oxidant gas side folded portion 325 as an internal flow path forming member that secures the internal flow path space 360 is at least part of the position where the opening 323 is formed in the metal plate, and the opening 323 side. This side is folded back to the power generation module 200 side as a folding line. In each folded portion, a communication hole 326 that communicates each manifold with the internal flow path space 350 and the internal flow path space 360 is formed. Therefore, in the fuel cell 100 of the first embodiment, the internal flow path spaces 350 and 360 are secured by separate components while suppressing short-circuits by suppressing the movement of the folded portions toward the anode separator 310 side. Compared with the case where it does, reduction of a number of parts, simplification of a manufacturing process, and reduction of cost can be aimed at.

B. Second embodiment:
FIG. 10 is an explanatory diagram showing a cross-sectional configuration of the unit cell 140a that constitutes the fuel cell according to the second embodiment. FIG. 10A shows a cross-section corresponding to the position C1-C1 in FIG. 3B, and FIG. 10B shows a cross-section corresponding to the position D1-D1 in FIG. 3B. Show.

  The configuration of the single cell 140a in the second embodiment is different from the configuration of the single cell 140 in the first embodiment in the configuration in the vicinity of the inner end along the surface direction of the oxidant gas side folded portion 325. The other points are the same as the configuration of the single cell 140 in the first embodiment. As shown in FIGS. 10A and 10B, in the single cell 140a of the second embodiment, at the position facing the oxidant gas supply manifold 152, the end of 230 is formed by the cathode side diffusion layer 217. The inner end portion (portion indicated by OL in the drawing) along the surface direction of the oxidant gas side folded portion 325 protrudes outward in the X direction, and the anode side separator 310 side of the cathode side porous channel layer 230 is on the anode side separator 310 side. It is in contact with the surface (the inner surface in the stacking direction). That is, the oxidant gas side folded portion 325 and the cathode side porous channel layer 230 are overlapped along the stacking direction. Although not shown, similarly, at the position facing the oxidant gas discharge manifold 154, the end of the cathode-side porous channel layer 230 protrudes outward in the X direction from the cathode-side diffusion layer 217, and the oxidant The inner end along the surface direction of the gas-side folded portion 325 is in contact with the surface of the cathode-side porous channel layer 230 on the anode-side separator 310 side.

  The surface of the portion OL that overlaps the oxidant gas side folded portion 325 along the stacking direction from the position corresponding to the outer end portion along the surface direction of the cathode side diffusion layer 217 in the cathode side porous channel layer 230. Sealing treatment is applied to a portion up to a position corresponding to the inner end along the direction. The sealing process is, for example, a process of filling the voids in the cathode-side porous channel layer 230 by impregnating the cathode-side porous channel layer 230 with a resin. In addition, as a sealing process, the process which crushes the cathode side porous body flow-path layer 230 and eliminates an internal space | gap may be performed.

  Thus, in the fuel cell 100 of the second embodiment, the inner end along the surface direction of the oxidant gas side folded portion 325 contacts the surface of the cathode side porous channel layer 230 on the anode side separator 310 side. Therefore, even if the sealing material 440 is filled with the overlap portion between the oxidant gas side folded portion 325 and the cathode side porous body flow path layer 230 so as to ensure gas sealing performance, The material 440 is prevented from entering the internal flow path space 360. Therefore, in the fuel cell 100 according to the second embodiment, both the securing of the reaction gas flow path and the securing of the gas sealing property at the reaction gas lead-in / out portion are suppressed while suppressing the complexity of the processing steps and the increase in the size of the fuel cell. Can be achieved. In particular, in the fuel cell 100 of the second embodiment, the oxidant gas side folded portion 325 and the oxidant gas side folded portion 325 from the position corresponding to the outer end portion along the surface direction of the cathode side diffusion layer 217 in the cathode side porous channel layer 230. Since the sealing process is performed on the portion up to the position corresponding to the inner end along the surface direction of the portion OL that overlaps along the stacking direction, the sealing material is inside the cathode-side porous channel layer 230. The entry into the internal flow path space 360 through the gap is satisfactorily suppressed, and it is possible to reliably achieve both the securing of the reaction gas flow path and the securing of the gas sealing property in the reaction gas lead-in / out section.

C. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

  The configuration of the fuel cell system 10 in each of the above embodiments is merely an example, and the configuration of the fuel cell system 10 can be variously changed. For example, in each of the above embodiments, the internal flow space 350, 360 is formed (secured) by the fuel gas side folded portion 322 and the oxidant gas side folded portion 325, but the fuel gas side folded portion 322 and the oxidant Instead of forming the gas side folded portion 325, the internal flow path spaces 350 and 360 are secured by forming the internal flow path forming member with metal or resin as a separate component from the anode side separator 310 and the cathode side separator 320. It is good. Also in this case, the inner end portion along the surface direction of the internal flow path forming member is the surface on the cathode side separator 320 side of the cathode side diffusion layer 217 and the anode side separator 310 side of the cathode side porous flow path layer 230. By adopting a configuration that is in contact with one of the surfaces of the substrate, it is possible to secure a reaction gas flow path and a gas sealing property in the reaction gas lead-in / out section while suppressing the complexity of the processing process and the increase in the size of the fuel cell. A balance with securing can be achieved.

  In each of the above embodiments, the power generation module 200 includes the anode-side porous flow path layer 220 and the cathode-side porous flow path layer 230. However, the power generation module 200 includes the anode-side porous flow path layer 220 and One or both of the cathode-side porous flow path layers 230 may not be included.

  Further, in the single cell 140 of each of the above embodiments, the cathode side and the anode side may be reversed. That is, in the configuration of the unit cell 140 of each of the above embodiments, the folded portions 322 and 325 are formed on the cathode side separator 320, and the folded portion is not formed on the anode side separator 310. It is also possible to adopt a configuration in which the folded portion is formed in the separator 310 and the folded portion is not formed in the cathode side separator 320.

  In each of the above embodiments, the length of the electrolyte membrane 212, the anode side diffusion layer 216, and the anode side porous body flow path layer 220 along the X direction is longer than the lengths of the other layers constituting the power generation module 200. However, only the length of the electrolyte membrane 212 may be longer than the other layers, and the lengths of the anode side diffusion layer 216 and the anode side porous body flow path layer 220 may be the same as those of the other layers.

  Further, in each of the above embodiments, a plurality of communication holes 326 are provided in the vertical portion of the folded portions 322 and 325, but a continuous slit-like opening may be provided instead of the plurality of communication holes 326. Good. In the above embodiments, the material of each part constituting the fuel cell 100 is specified. However, the material is not limited to these materials, and various appropriate materials can be used. For example, the cathode-side porous flow path layer 230 and the anode-side porous flow path layer 220 are formed using a metal porous body, but may be formed using other materials such as a carbon porous body. .

  Further, in each of the above embodiments, the folded portion is adjacent to all the openings constituting each manifold (oxidant gas supply manifold 152, fuel gas supply manifold 162, oxidant gas discharge manifold 154, fuel gas discharge manifold 164). Although it is formed, a folded portion may be formed adjacent to only some of the openings.

  Further, the arrangement of the manifolds in the unit cell 140 of each of the above embodiments is merely an example, and different arrangements of the manifolds can be employed.

DESCRIPTION OF SYMBOLS 10 ... Fuel cell system 50 ... Hydrogen tank 51 ... Shut valve 52 ... Regulator 53 ... Piping 54 ... Discharge piping 60 ... Air pump 61 ... Piping 63 ... Discharge piping 70 ... Radiator 71 ... Water pump 72 ... Piping 73 ... Piping 100 ... Fuel cell 110 ... End plate 120 ... Insulating plate 130 ... Current collecting plate 140 ... Single cell 152 ... Oxidant gas supply manifold 154 ... Oxidant gas discharge manifold 162 ... Fuel gas supply manifold 164 ... Fuel gas discharge manifold 172 ... Cooling medium supply manifold 174 ... cooling medium discharge manifold 200 ... power generation module 210 ... membrane electrode assembly 212 ... electrolyte membrane 214 ... anode 215 ... cathode 216 ... anode side diffusion layer 217 ... cathode side diffusion layer 220 ... anode side porous body flow path layer 2 DESCRIPTION OF SYMBOLS 0 ... Cathode side porous body flow path layer 310 ... Anode side separator 311 ... Opening 312 ... Convex part 313 ... Opening 315 ... Convex part 317 ... End part bending part 319 ... Dimple 320 ... Cathode side separator 321 ... Opening 322 ... Fuel gas side Folded portion 323 ... Opening 324 ... Protruding portion 325 ... Oxidant gas side folded portion 326 ... Communication hole 327 ... Convex portion 329 ... Convex portion 350 ... Internal flow path space 360 ... Internal flow path space 410 ... Sealing material 420 ... Sealing material 430 ... Filler 440 ... Sealing material 450 ... Sealing material 500 ... Gasket 502 ... Projection

Claims (5)

A fuel cell,
A power generation module having a membrane electrode assembly including an electrolyte membrane and electrode layers disposed on both surfaces of the electrolyte membrane, and a pair of diffusion layers stacked so as to sandwich the membrane electrode assembly layer;
The first and second separators are formed by processing a metal plate and are arranged so as to sandwich the power generation module, and are located outside a position facing the power generation module along the surface direction of the power generation module. First and second separators having openings constituting a plurality of reaction gas flow paths substantially perpendicular to the surface direction at positions;
The reaction gas flow path for the reaction gas used in the electrode layer on the first separator side between the first separator and the surface direction on the first separator side of the power generation module. A first internal flow path forming member that forms a first internal flow path space that communicates with the end portion;
The reaction gas flow path for the reaction gas used in the electrode layer on the second separator side between the first separator and the surface direction on the second separator side of the power generation module. A second internal flow path forming member that forms a second internal flow path space that communicates with the end,
A seal member that seals between the first internal flow path forming member and the second internal flow path forming member and the second separator;
An inner end portion of the first internal flow path forming member along the surface direction is in contact with the surface of the diffusion layer on the first separator side on the first separator side. The fuel cell according to claim 1,
In the first internal flow path forming member and the second internal flow path forming member, at least a part of the metal plate at a position where the opening of the first separator is formed is on the power generation module side of the opening. Is formed by a folded portion formed by folding back to the power generation module side as a folding line,
The folded portion has a communication hole that communicates the reaction gas flow path with the first internal flow path space and the second internal flow path space. A fuel cell,
A membrane electrode assembly including an electrolyte membrane and electrode layers disposed on both sides of the electrolyte membrane; a pair of diffusion layers stacked so as to sandwich the membrane electrode assembly layer; and each of the pair of diffusion layers A power generation module having a pair of porous flow path layers stacked on the outside;
The first and second separators are formed by processing a metal plate and are arranged so as to sandwich the power generation module, and are located outside a position facing the power generation module along the surface direction of the power generation module. First and second separators having openings constituting a plurality of reaction gas flow paths substantially perpendicular to the surface direction at positions;
The reaction gas flow path for the reaction gas used in the electrode layer on the first separator side between the first separator and the surface direction on the first separator side of the power generation module. A first internal flow path forming member that forms a first internal flow path space that communicates with the end portion;
The reaction gas flow path for the reaction gas used in the electrode layer on the second separator side between the first separator and the surface direction on the second separator side of the power generation module. A second internal flow path forming member that forms a second internal flow path space that communicates with the end,
A seal member that seals between the first internal flow path forming member and the second internal flow path forming member and the second separator;
The inner end along the surface direction of the first internal flow path forming member includes the surface on the first separator side of the diffusion layer on the first separator side and the surface on the first separator side. A fuel cell in contact with one of the surface of the porous body flow path layer on the second separator side. The fuel cell according to claim 3, wherein
In the first internal flow path forming member and the second internal flow path forming member, at least a part of the metal plate at a position where the opening of the first separator is formed is on the power generation module side of the opening. Is formed by a folded portion formed by folding back to the power generation module side as a folding line,
The folded portion has a communication hole that communicates the reaction gas flow path with the first internal flow path space and the second internal flow path space. The fuel cell according to claim 3 or 4, wherein
The inner end along the surface direction of the first internal flow path forming member is in contact with the surface on the second separator side of the porous flow path layer on the first separator side,
The porous body flow path layer on the first separator side overlaps the first internal flow path forming member along the stacking direction from a position corresponding to the outer end portion along the surface direction of the diffusion layer. A fuel cell in which a portion up to a position corresponding to an inner end portion along the surface direction of the portion is subjected to sealing treatment.

Images