JP2012003858A - Fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a uniform distribution property of reaction gas while reducing the thickness of a fuel battery cell.SOLUTION: First and second separators of a fuel battery cell each have an opening which forms a reaction gas channel at a location outward from the position facing a membrane electrode assembly. The first separator comprises: a first communication hole which communicates the reaction gas channel on the first separator side with a first internal channel space communicating to an end face of a porous channel layer on the first separator side; and a second communication hole which communicates the reaction gas channel on the second separator side with a second internal channel space communicating to a grooved internal channel space extending along an outer edge of at least one of the upstream and the downstream of a reaction gas flow direction in a porous channel layer on the second separator side. At least one of the first and second separators comprises: a sealing part for sealing between the first and second separators; and a rib extending along the grooved internal channel space at a boundary with the grooved internal channel space.

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.

  In the fuel cell in which the power generation module includes a membrane electrode assembly and a gas diffusion plate formed of a porous body, a gap extending along the upstream and downstream outer edges of the reaction gas in the gas diffusion plate A technique for improving the uniform distribution of the reaction gas by providing a portion is known (see, for example, Patent Document 1).

JP 2008-186788 A

  In the conventional fuel cell, the reaction gas flows from the manifold into the flow path space provided inside the separator, and passes through the supply port provided on the surface of the separator facing the gas diffusion plate, upstream of the gas diffusion plate. Supplied in the gap, flows in the gas diffusion plate from the upstream gap toward the downstream gap, and is provided in the separator through the discharge port provided on the surface of the separator facing the gas diffusion plate. It is discharged to the flow path space and discharged to the manifold through the flow path space. For this reason, the conventional fuel cell has a problem that the thickness of the fuel cell becomes relatively thick.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to improve the uniform distribution of the reaction gas while reducing the thickness of the fuel cell in the fuel cell.

  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 plurality of stacked fuel cells; and
A plurality of reaction gas passages that are substantially parallel to the stacking direction of the fuel cells and circulate the reaction gas used in each fuel cell, and
Each of the fuel cells is
A membrane electrode assembly comprising an electrolyte membrane and electrode layers disposed on both sides of the electrolyte membrane;
A pair of porous channel layers formed of a porous material and disposed so as to sandwich the membrane electrode assembly;
A first separator and a second separator formed by processing a metal plate and disposed so as to sandwich the pair of porous channel layers,
The first and second separators have openings constituting the reaction gas flow channel at positions outside the surface direction from positions facing the membrane electrode assembly and the porous flow channel layer,
The first separator communicates with an end surface of the reaction gas channel for the reaction gas used in the electrode layer on the first separator side and an end surface of the porous channel layer on the first separator side. A first communication hole communicating with one internal flow path space, the reaction gas flow path for the reaction gas used in the electrode layer on the second separator side, and the porosity on the second separator side. A second communication hole that communicates with a second internal flow path space that communicates with a groove-type internal flow path space that extends along at least one outer edge on the upstream side and the downstream side in the reaction gas flow direction in the body flow path layer; Have
At least one of the first and second separators is located at a position of a boundary between the seal portion that seals between the first and second separators and the groove-type internal flow space, and the groove-type internal flow space. A fuel cell having ribs extending along.

  In this fuel cell, on the first separator side, the first internal flow that communicates with the reaction gas flow path and the end face of the porous flow path layer through the first communication hole formed in the first separator. A groove-type interior that communicates with the end space of the reaction gas channel and the porous channel layer through the second communication hole formed in the first separator on the second separator side. Since the second internal flow path space communicating with the flow path space communicates, the thickness of the fuel cell can be reduced as compared with the conventional fuel cell. Further, in this fuel cell, a rib extending along the groove-type internal flow path space is formed at the boundary between the seal portion that seals between the first and second separators and the groove-type internal flow path space. The inflow of the sealing material into the groove-type internal flow path space is prevented, and the groove-type internal flow path space functions as a common rail, improving the uniform distribution of the reaction gas. Therefore, in this fuel cell, the uniform distribution of the reaction gas can be improved while reducing the thickness of the fuel cell.

[Application Example 2] The fuel cell according to Application Example 1,
The first separator has at least a part of the metal plate at a position where the opening constituting the reaction gas flow path for the reaction gas used in the electrode layer on the first separator side is formed. A first folded portion formed by folding the side of the opening on the membrane electrode assembly side as a folding line to the membrane electrode assembly side, and a reactive gas used in the electrode layer on the second separator side At least a part of the metal plate at a position where the opening constituting the reaction gas flow path is formed is formed by folding the side of the opening on the membrane electrode assembly side to the membrane electrode assembly side. A second folded portion,
The first internal channel space is formed between the first folded portion and the first separator,
The second internal channel space is formed between the second folded portion and the first separator,
The first communication hole is formed in the first folded portion,
The second communication hole is a fuel cell formed in the second folded portion.

  This fuel cell can improve the uniform distribution of the reaction gas while reducing the thickness of the fuel cell. In addition, the reaction gas can be derived while reducing the number of parts, simplifying the processing process, and reducing the cost. It is possible to achieve both the securing of the gas flow path at the entrance and the securing of the gas sealing property.

[Application Example 3] The fuel cell according to Application Example 1 or Application Example 2,
Each fuel cell further comprises:
In each of the first separator side and the second separator side, including a diffusion layer disposed between the electrode layer and the porous channel layer,
The length of the porous channel layer on the second separator side is such that at least the position of the outer edge on the upstream side and the downstream side in the reaction gas flow direction in the porous channel layer is the length on the second separator side. Shorter than the length of the diffusion layer,
The groove-type internal flow path space is a fuel cell, which is a space formed between the second separator and the diffusion layer on the second separator side.

  In this fuel cell, since the space formed between the second separator and the diffusion layer on the second separator side can be used as a groove-type internal flow path space, an increase in the size of the fuel cell is suppressed. However, the uniform distribution of the reaction gas can be improved.

[Application Example 4] The fuel cell according to Application Example 3,
The second separator has a plurality of convex portions protruding in the direction of the membrane electrode assembly at a portion facing the groove-type internal flow path space.

  In this fuel cell, the second separator-side diffusion layer can be supported by a plurality of convex portions, and a groove-type internal flow path space is ensured between the second separator and the second separator-side diffusion layer. Can be secured.

[Application Example 5] The fuel cell according to Application Example 4,
At least one of the plurality of convex portions is a fuel cell arranged near an outer edge of the porous channel layer on the second separator side.

  In this fuel cell, the convex portion disposed near the outer edge of the porous body flow path layer on the second separator side functions as a positioning reference when the porous flow path layer is disposed. Simplification and improvement in accuracy can be achieved.

  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. 3 is a perspective view showing a configuration near an opening 323 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. FIG. 6 is an explanatory diagram showing a state of press molding 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 in 2nd Example. It is explanatory drawing which shows schematically the shape of the area | region facing the anode side porous body flow path layer shortening part in the anode side separator 310a of 2nd Example.

Next, embodiments of the present invention will be described in the following order based on examples.
A. First embodiment:
B. Second embodiment:
C. Variations:

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. The fuel cell 100 includes an end plate 110, an insulating plate 120, a current collecting plate 130, a plurality of single cells (fuel cell) 140, a current collecting plate 130, an insulating plate 120, and an end plate 110. The stack structure is stacked in this order.

  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, antifreeze water 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 shown in the figure, the planar shape of the single cell 140 is substantially rectangular. As will be described later, the unit cell 140 includes a pair of power generation modules 200 including a membrane electrode assembly (MEA) in which an anode (anode electrode layer) and a cathode (cathode electrode layer) are arranged on each surface of an electrolyte membrane. The structure is sandwiched between separators.

  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 flow channel having a shape extending in a direction substantially parallel to the stacking direction of the single cells 140 of the fuel cell 100 (that is, a direction substantially perpendicular to the surface direction of the membrane electrode assembly). 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.

  As shown in FIG. 2, the position of each manifold in the plane of the single cell 140 is the peripheral edge of the single cell 140. Specifically, the position of the fuel gas supply manifold 162 is at one end (the same as the upper end) of one short side (the right short side in FIG. 2) of the power generation module 200 in the plane of the single cell 140. The fuel gas discharge manifold 164 is located adjacent to the other end (the lower end) of the other short side (the left short side) of the power generation module 200. . Further, the position of the oxidant gas supply manifold 152 is a position adjacent to the entire one long side of the power generation module 200 (the upper long side), and the position of the oxidant gas discharge manifold 154 is the other side of the power generation module 200. This is a position adjacent to the entire long side (the same as the lower long side). In addition, the position of the cooling medium supply manifold 172 is a position adjacent to one short side (the same short side on the left side) of the power generation module 200, and the position of the cooling medium discharge manifold 174 is the other short side of the power generation module 200 ( This is a position adjacent to the right short side.

  In the following description, the direction in which the single cells 140 are stacked in the fuel cell 100 is referred to as the “stacking direction”, and the direction parallel to the main surface of each layer constituting the power generation module 200 (that is, substantially perpendicular to the stacking direction). Direction) is referred to as “plane direction”. Of the surface directions, a direction parallel to the short side of the power generation module 200 is referred to as a Y direction, and a direction parallel to the long side of the power generation module 200 (a direction substantially perpendicular to the Y direction) is referred to as an X direction. .

  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 a C1-C1 cross section of FIG. 3B, FIG. 4B shows a D1-D1 cross section of FIG. 3B, and FIG. Shows the A1-A1 cross section of FIG. 3 (a), and FIG. 5 (b) shows the B1-B1 cross section of FIG. 3 (a).

  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 (cathode electrode layer) 215 disposed (coated) on one side of the electrolyte membrane 212, and an anode disposed (coated) on the other side of the electrolyte membrane 212. (Anode electrode layer) 214. 2 and 3, the approximate 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.

  As shown in FIG. 4, at the position facing the oxidant gas supply manifold 152, the surface direction of the electrolyte membrane 212 and the anode-side layers (the anode 214, the anode-side diffusion layer 216, and the anode-side porous channel layer 220) ( The length along the Y direction is longer than the lengths of the other layers (cathode 215, cathode side diffusion layer 217, cathode side porous channel 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, each layer on the electrolyte membrane 212 and the anode side protrudes from the other layers. A protective layer made of PEN or the like may be provided on the cathode side surface of the protruding portion of the electrolyte membrane 212 in order to improve durability and handling properties.

  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 323 constituting an oxidant gas supply manifold 152, and FIGS. 5 (a) and 5 (b). As shown in b), an opening 321 constituting the fuel gas supply manifold 162 is formed.

  FIG. 6 is a perspective view showing a configuration near the opening 323 of the cathode separator 320. As shown in FIGS. 4 and 6, a folded portion 325 is formed at a position adjacent to the opening 323 for constituting the oxidant gas supply manifold 152 of the cathode side separator 320. As will be described in detail later, the folded portion 325 is such that at least a part of the position where the opening 323 is formed in the metal plate as the material of the cathode side separator 320 is the side of the opening 323 on the membrane electrode assembly 210 side. As a fold line, it is folded in the inner direction along the stacking direction of the single cells 140 (the direction toward the anode-side separator 310) and in the inner direction along the Y direction (the direction toward the membrane electrode assembly 210). ,It is formed.

  As shown in FIGS. 4A and 4B, the folded portion 325 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 325 is slightly closer to the cathode side than the position of the electrolyte membrane 212. 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 (FIG. 4B). )reference). 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 X direction (see FIG. 6). The internal flow path space 360 corresponds to the first internal flow path space in the present invention. The oxidizing gas side folded portion 325 corresponds to the first folded portion in the present invention, and the communication hole 326 formed in the oxidant gas side folded portion 325 corresponds to the first communicating hole in the present invention. .

  A convex portion 324 having a convex shape in the direction toward the anode separator 310 (that is, a shape projecting into the internal channel space 360) is located at the position of the cathode side separator 320 facing the parallel portion of the folded portion 325 along the stacking direction. A plurality of are formed. The plurality of convex portions 324 are arranged side by side at predetermined intervals along the X direction so that positions along the X direction do not overlap with the communication holes 326 (see FIG. 3B and FIG. 6). ). Each convex portion 324 has a substantially rectangular plane extending in the Y 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 (see FIG. 4A).

  Similarly, as shown in FIGS. 5A and 5B, a folded portion 322 is formed at a position adjacent to the opening 321 for constituting the fuel gas supply manifold 162 in the cathode separator 320. Yes. In the folded portion 322, 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 is a single cell 140 with the side of the opening 321 on the membrane electrode assembly 210 side being a folding line. It is formed by being folded back in the inner direction along the stacking direction and in the inner direction along the X direction. The folded portion 322 includes a vertical portion substantially perpendicular to the surface direction and a parallel portion substantially parallel to the surface direction. The position along the stacking direction of the parallel portion of the folded portion 322 is slightly closer to the cathode side than the position of the electrolyte membrane 212, similarly to the folded portion 325. 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 (FIG. 5B). )reference). A plurality of communication holes 326 for communicating the fuel gas supply manifold 162 and the internal flow path 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. The internal flow path space 350 corresponds to the second internal flow path space in the present invention. The fuel gas side folded portion 322 corresponds to the second folded portion in the present invention, and the communication hole 326 formed in the fuel gas side folded portion 322 corresponds to the second communication hole in the present invention.

  A convex portion 324 having a convex shape in the direction toward the anode-side separator 310 (that is, a shape projecting into the internal channel space 350) is located at the position of the cathode-side separator 320 facing the parallel portion of the folded portion 322 along the stacking direction. Are formed (see FIG. 3A). 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 (see FIG. 5A).

  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. 5 (a) and 5 (b), the length along the plane direction (X direction) of the parallel portion of the fuel gas side folded portion 322 is different from that of the electrolyte membrane 212 along the stacking direction. The length is too long. On the other hand, as shown in FIGS. 4A and 4B, the length along the plane direction (Y direction) of the parallel portion of the oxidizing gas side folded portion 325 is along the stacking direction. The length overlaps with the electrolyte membrane 212. 3A and 3B, the positions of the parallel portions of the fuel gas side folded portion 322 and the oxidant gas side folded portion 325 in the plane of the single cell 140 are indicated by hatching.

  In addition, a convex portion 336 that protrudes in the direction toward the anode-side separator 310 is formed in the vicinity of the oxidant gas supply manifold 152 in the cathode-side separator 320 (see FIG. 4A). The convex portion 336 is formed at a position facing the convex portion 324 in the portion where the oxidizing gas side folded portion 325 is formed. The surface of the convex portion 336 on the anode side separator 310 side is in contact with the surface of the oxidant gas side folded portion 325 on the cathode side separator 320 side. The cathode-side separator 320 is formed with a convex portion 327 that protrudes in the direction toward the anode-side separator 310 in the vicinity of the fuel gas supply manifold 162 (see FIGS. 5A and 5B). .

  As shown in FIGS. 3 to 5, the cathode-side separator 320 includes a position surrounding three sides other than the side where the fuel gas-side folded portion 322 of the opening 321 is formed, and the oxidant gas side of the opening 323. A convex portion 329 that protrudes in the direction toward the anode separator 310 is formed at a position surrounding three sides other than the side where the folded portion 325 is formed. 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.

  Also, as shown in FIGS. 4A and 4B, a plurality of dimples 319 are formed in a region facing the cathode-side porous flow path layer 230 of the cathode-side separator 320. The outermost position along the stacking direction of the dimples 319 is the same as the position of the other part of the cathode separator 320 (the part excluding the convex part 324 and the convex part 336). Of the region facing the cathode-side porous channel layer 230 of the cathode-side separator 320, the portion other than the portion where the dimple 319 is formed is in contact with the surface of the cathode-side porous channel layer 230.

  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, as shown in FIG. 5, in the anode side separator 310, the cathode side separator 320 faces the cathode side separator 320 at a position facing the parallel portion of the fuel gas side folded portion 322 and a position facing the convex portion 329. A convex portion 312 that is convex in the direction 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, as shown in FIG. 4, in the anode side separator 310, the position facing the portion near the oxidant gas supply manifold 152 in the parallel portion of the oxidant gas side folded portion 325 of the cathode side separator 320 and the convex portion 329 are opposed. A protruding portion 315 that protrudes in the direction toward the cathode-side separator 320 is formed at the position. 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. As shown in FIG. 4, the position of the innermost portion in the surface direction of the convex portion 315 formed at the position facing the oxidant gas side folded portion 325 of the anode side separator 310 is the electrolyte membrane 212 and each layer on the anode side. It is a position outside the outer edge (end surface) of the (anode 214, anode side diffusion layer 216, anode side porous channel layer 220) by a predetermined length L1.

  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. 5A and 5B, 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, and the cathode side separator 320 of FIG. A space between the convex portion 329 and the convex portion 312 of the anode separator 310 is sealed with a sealing material 420. Also, as shown in FIGS. 4A and 4B, the gap 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 is on the oxidant gas side. A seal material 420 seals between the parallel portion of the folded portion 325 and the electrolyte membrane 212 and between the convex portion 329 of the cathode side separator 320 and the convex portion 315 of the anode side separator 310. Each sealing material exhibits a sealing function and a short-circuit prevention function at the seal location. As the sealing material, for example, an adhesive or a thermoplastic resin is used. The positions along the stacking direction of the sealing materials 420 are substantially the same.

  As shown in FIGS. 4A and 4B, a rib 372 protruding in the direction toward the anode side separator 310 is formed in the oxidant gas side folded portion 325. The ribs 372 are located at positions adjacent to the outer edge (end surface) of the electrolyte membrane 212 and each layer on the anode side (the anode 214, the anode side diffusion layer 216, and the anode side porous body flow path layer 220), and the oxidant gas side folded portion 325. The ribs 372 are provided at two locations, the position adjacent to the innermost surface portion of the convex portion 315 facing each other, and each rib 372 is parallel to the long side of the plane of the power generation module 200 (X direction). It extends along. The shape of the rib 372 adjacent to the outer edge of each layer on the electrolyte membrane 212 and the anode side is, for example, close to the outer edge of the electrolyte membrane 212 etc. It is a shape comprised from the diagonal plate-shaped part extended in the diagonal direction which leaves | separates from the said outer edge. Further, the shape of the rib 372 at a position adjacent to the convex portion 315 is, for example, a vertical plate portion close to the convex portion 315 and substantially parallel to the stacking direction, and an oblique direction away from the convex portion 315 from the tip of the vertical plate portion. It is the shape comprised from the slanting plate-shaped part extended. Due to the presence of these ribs 372, for example, when the single cell 140 is manufactured, the sealant 420 arranged between the parallel portion of the oxidant gas side folded portion 325 and the convex portion 315 moves inward in the plane direction. In addition, the sealing material 420 disposed between the parallel portion of the oxidant gas side folded portion 325 and the electrolyte membrane 212 is prevented from moving outward in the surface direction. Therefore, between the outer edge of each layer on the electrolyte membrane 212 and the anode side and the innermost portion in the surface direction of the convex portion 315 facing the oxidant gas side folded portion 325, the width of the plane of the power generation module 200 is approximately L1. A groove-type internal channel space CR extending in a direction parallel to the side is secured. The groove-type internal channel space CR is a space sandwiched between the oxidant gas side folded portion 325 and the anode side separator 310 (see FIG. 5B). 2 and 3, the approximate position of the groove-type internal channel space CR in the plane of the single cell 140 is indicated by a broken line.

  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 321 constituting the fuel gas discharge manifold 164 is formed in the cathode side separator 320 in the vicinity of the fuel gas discharge manifold 164 in the single cell 140, similarly to the vicinity of the fuel gas supply manifold 162 shown in FIG. Next to the opening 321, a folded portion 322 in which a part of the metal plate is folded in the direction of the membrane electrode assembly 210 is formed. The folded portion 322 is formed with a communication hole 326 that communicates the internal flow path space 350 formed between the folded portion 322 and the cathode separator 320 and the fuel gas discharge manifold 164. Further, in the vicinity of the oxidant gas discharge manifold 154 in the single cell 140, an opening 323 constituting the oxidant gas discharge manifold 154 is formed in the cathode side separator 320 in the same manner as the vicinity of the oxidant gas supply manifold 152 shown in FIG. Next, a folded portion 325 in which a part of the metal plate is folded in the direction of the membrane electrode assembly 210 is formed next to the opening 323. In the folded portion 325, a communication hole 326 is formed to communicate the internal flow path space 360 formed between the folded portion 325 and the cathode side separator 320 and the oxidizing gas discharge manifold 154. In addition, a sealing material 420 disposed between the parallel portion of the oxidant gas side folded portion 325 and the convex portion 315 is also provided on the inner side in the surface direction at the folded portion 325 formed adjacent to the oxidant gas discharge manifold 154. A rib for preventing the sealant 420 disposed between the parallel portion of the oxidant gas side folded portion 325 and the electrolyte membrane 212 from moving toward the outside in the surface direction. 372 is formed. Therefore, in the vicinity of the folded portion 325 formed adjacent to the oxidant gas discharge manifold 154, the outermost edge of each layer on the electrolyte membrane 212 and the anode side and the convex portion 315 facing the oxidant gas side folded portion 325 are arranged in the surface direction. Between the inner portion, a groove-type internal flow path space CR having a width of approximately L1 and extending in a direction parallel to the long side of the plane of the power generation module 200 is secured (see FIG. 2).

  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 portions 502 of the gasket 500 arranged in a single cell 140 are formed on the surfaces of the convex portions 312 and 315 of the anode-side separator 310 of another adjacent single cell 140 when the plurality of single cells 140 are stacked. The seal line SL is formed in close contact. 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.

  Further, when the plurality of single cells 140 are stacked, the outermost surface in the stacking direction of the dimples 319 contacts the surface of the anode-side separator 310 of another single cell 140 adjacent along 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 by arrows in FIGS. 4A and 4B, the air as the oxidant gas supplied to the oxidant gas supply manifold 152 passes through the communication hole 326 formed in the fuel gas side folded portion 322. To the internal flow path space 360. The internal channel space 360 communicates with the end face of each layer on the cathode side of the power generation module 200 (cathode 215, cathode side diffusion layer 217, cathode side porous channel layer 230). Therefore, the oxidant gas guided to the internal channel space 360 reaches the cathode side end surface of the power generation module 200 and enters the cathode side porous channel layer 230 having the smallest internal channel resistance. Thereafter, the oxidant gas is supplied to the cathode side diffusion layer 217 and the cathode 215 while flowing in the cathode side porous channel layer 230 toward the discharge side. The oxidant gas that has not been used in the power generation module 200 is discharged from the cathode-side porous flow path layer 230 to the internal flow path space 360 formed on the oxidant gas discharge manifold 154 side, and to the oxidant gas discharge manifold 154 side. It is discharged to the oxidant gas discharge manifold 154 through the formed communication hole 326.

  5A and 5B, hydrogen as the fuel gas supplied to the fuel gas supply manifold 162 is communicated with a communication hole 326 formed in the oxidant gas side folded portion 325. To the internal flow path space 350. Here, the internal flow path space 350 communicates with the groove-type internal flow path space CR (see FIGS. 3A and 5B). Further, the groove-type internal channel space CR faces the end surface of the anode-side porous channel layer 220 of the power generation module 200 (see FIG. 4). Therefore, the fuel gas introduced into the internal flow path space 350 enters the groove-type internal flow path space CR and passes through the groove-type internal flow path space CR in a direction parallel to the long side of the plane of the power generation module 200 (X The anode-side porous flow path layer 220 while diffusing along the direction. Thereafter, the fuel gas is supplied to the anode-side diffusion layer 216 and the anode 214 while flowing in the anode-side porous channel layer 220 toward the discharge side. The fuel gas that has not been used in the power generation module 200 is discharged into the groove-type internal flow path space CR on the downstream side, and the internal flow path formed on the fuel gas discharge manifold 164 side through the groove-type internal flow path space CR. It is guided to the space 350 and further discharged to the fuel gas discharge manifold 164 through a communication hole 326 formed in the fuel gas discharge manifold 164.

  In FIG. 2, the above-described fuel gas flow path in the plane of the single cell 140 is indicated by arrows. As can be seen from FIG. 2, in this embodiment, the groove-type internal flow path space CR is formed so as to extend along the upstream and downstream outer edges of the anode-side porous flow path layer 220 in the fuel gas flow direction. Has been. Therefore, the groove-type internal flow path space CR functions as a so-called common rail that improves the uniform distribution of the fuel gas.

  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 in the vicinity of the opening 323 constituting the oxidant gas supply manifold 152 of the cathode-side separator 320 at each stage of the molding process.

  In step S <b> 210 of the forming process of the cathode side separator 320, press forming is performed on the metal plate as the material of the cathode side separator 320. In this press molding process, the convex portion 324 is formed. FIG. 10A shows a state in which a convex portion 324 is formed by pressing a metal plate as a material of the cathode-side separator 320 with the press P. In addition, the part in which the convex part 324 in a metal plate is not formed becomes the internal flow path space 360 (or internal flow path space 350). As shown in FIG. 9A, the convex portion 324 is formed at a position on the inner side in the surface direction (on the membrane electrode assembly 210 side) from a position where the opening 323 (or the opening 321) is formed in the metal plate. In the press forming process, as shown in FIG. 9A, ribs 372 are formed at positions where the openings 323 are formed (that is, positions where the oxidant gas side folded-back portions 325 are formed). FIG. 10B shows a state in which a rib 372 is formed by pressing a metal plate as a material of the cathode side separator 320 with another press P. In this press molding process, in addition to the convex portions 324 and the ribs 372, convex portions 327, convex portions 329, convex portions 336, dimples 319, and the like are also formed.

  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. As shown in FIG. 9B, the communication hole 326 is formed in a position so as to be aligned near the fold line of the opening 323 (or the opening 321) and not to face 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 oxidant gas side folded portion 325 and the fuel gas side folded portion 322. In the bending process, as shown in FIG. 9C, the opening 323 (or opening 321) is formed in the metal plate, and a part of the portion where the opening 323 is formed is bent inward in the surface direction. It is done. As a result, the cathode side separator 320 is formed with an opening 323 constituting the oxidant gas supply manifold 152 and the oxidant gas discharge manifold 154 and an opening 321 constituting the fuel gas supply manifold 162 and the fuel gas discharge manifold 164. At the same time, an oxidant gas side folded portion 325 and a fuel gas side folded portion 322 are 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, the metal plate as a material is subjected to press molding to form the opening 311 and the opening 313, and the convex portion 312 and the convex portion 315. In step S <b> 130, the sealing material 420 is disposed on the cathode side separator 320. The sealing material 420 is disposed at the position 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 S160, joining by thermocompression bonding is performed in the laminated state, and the manufacture of the single cell 140 is completed.

  As described above, in the fuel cell 100 of the first embodiment, each cathode (the fuel gas supply manifold 162, the fuel gas discharge manifold 164, the oxidant gas supply manifold 152, the oxidant gas discharge manifold 154) is connected to the cathode separator 320. Are formed, and the anode separator 310 is also formed with openings 311 and 313 that constitute each manifold. In the single cell 140, an internal flow path space 360 communicating with the end face of the cathode-side porous flow path layer 230 and an internal flow path space 350 communicating with the groove-type internal flow path space CR are formed. The cathode separator 320 includes a communication hole 326 that connects the oxidant gas supply manifold 152, the oxidant gas discharge manifold 154, and the internal flow space 360, and a fuel gas supply manifold 162, a fuel gas discharge manifold 164, and an internal A communication hole 326 communicating with the flow path space 350 is formed. Therefore, in the fuel cell 100 of the first embodiment, the reaction gas is formed between the reaction gas manifold and the end face of the power generation module 200 via the flow path space formed on the cathode side separator 320 on both the anode side and the cathode side. Is exchanged. Therefore, in the fuel cell 100 of the first embodiment, the reactive gas flow path space and the porous body flow provided in the separator via the supply port and the discharge port provided on the surface of the separator facing the porous body flow layer. The thickness of the unit cell 140 can be reduced as compared with a conventional fuel cell that exchanges reaction gas with the road layer.

  Further, in the fuel cell 100 of the first embodiment, the oxidizing gas side folded portion 325 of the cathode side separator 320 has a sealing material 420 that seals between the cathode side separator 320 and the anode side separator 310, and a groove-type internal flow path. A rib 372 is formed at a boundary with the space CR and extends along the groove-type internal flow path space CR. Therefore, the sealing material 420 disposed between the cathode side separator 320 and the anode side separator 310 (between the oxidant gas side folded portion 325 and the convex portion 315) is prevented from moving inward in the surface direction. The groove-type internal flow path space CR is secured at the upstream and downstream outer edges of the anode-side porous flow path layer 220 in the fuel gas flow direction. Therefore, in the fuel cell 100 according to the first embodiment, a so-called common rail can be formed in the single cell 140 to improve the uniform distribution of the fuel gas. The thickness of the single cell 140 is not increased compared to the case where the flow path space is provided. Therefore, in the fuel cell 100 of the first embodiment, the uniform distribution of the reaction gas can be improved while reducing the thickness of the single cell 140.

  In the fuel cell 100 of the first embodiment, the oxidant gas side folded portion 325 includes a seal material 420 that seals between the oxidant gas side folded portion 325 and the electrolyte membrane 212, and a groove-type internal flow path space CR. Since the rib 372 extending along the groove-type internal flow path space CR is also formed at the boundary position, the sealing material 420 disposed between the parallel portion of the oxidant gas side folded portion 325 and the electrolyte membrane 212. Is prevented from moving outward in the surface direction, and the groove-type internal flow path space CR is more reliably secured. Further, in the fuel cell 100 of the first embodiment, since the movement of the sealing material 420 is prevented by the ribs 372, the amount of the sealing material 420 used can be reduced.

  Further, in the fuel cell 100 of the first embodiment, a step is not provided on the surface of the single cell 140 in order to form a so-called common rail inside the single cell 140, so that the thermocompression bonding process at the time of manufacturing the single cell 140 is performed. As a jig for use, a jig with a high flatness having only the minimum necessary unevenness on the workpiece side surface can be used, and as a result, the accuracy of the manufactured single cell 140 can be improved.

  Further, in the fuel cell 100 of the first embodiment, a membrane electrode assembly in which at least a part of the position where the opening 321 is formed in the metal plate as the material of the cathode side separator 320 is formed in the cathode side separator 320. A membrane electrode assembly in which at least a part of a position where the opening 323 is formed in the metal plate and a folded portion 322 formed by folding back to the membrane electrode assembly 210 side with the side on the 210 side as a fold line is formed. And a folded portion 325 formed by being folded back to the membrane electrode assembly 210 side with the side on the 210 side as a folding line. The internal flow space 360 is formed between the parallel portion of the oxidant gas side folded portion 325 and the cathode separator 320, and the oxidant gas supply manifold 152, the oxidant gas discharge manifold 154, and the internal flow space 360. Are formed in the oxidant gas side folded portion 325. The internal channel space 350 is formed between the parallel portion of the fuel gas side folded portion 322 and the cathode side separator 320, and communicates the fuel gas supply manifold 162 and the fuel gas discharge manifold 164 with the internal channel space 350. The communicating hole 326 is formed in the fuel gas side folded portion 322. Therefore, in the fuel cell 100 of the first embodiment, complication of the processing steps can be suppressed as compared with the case where the folded portions are formed on both the cathode side separator 320 and the anode side separator 310, and the gas in the reaction gas lead-in / out portion is reduced. It is possible to achieve both the securing of the flow path and the gas sealing property. In addition, 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 performance in the reaction gas lead-in / out section by using another part such as a resin frame or a resin film provided with the gas flow path. Compared with the case where it implement | achieves, reduction of a number of parts, simplification of a manufacturing process, and cost reduction can be aimed at.

  Further, in the fuel cell 100 according to the first embodiment, since the reaction gas is led in / out through the end face of the power generation module 200 in the reaction gas lead-in / out section, the reaction gas is placed on the stacked surface of the power generation module 200 (surface parallel to the surface direction) ), The electrode utilization rate can be improved and the drainage performance is reduced due to gas accumulation, compared with the case where both the gas flow path and the gas sealability are ensured. Can be suppressed. Furthermore, in the fuel cell 100 of the first embodiment, the backup function of the gasket 500 can be provided not on the electrode but on a metal separator, so that the durability of the electrode can be improved compared to the case where the backup function of the gasket 500 is provided on the electrode. Can be improved.

B. Second embodiment:
FIG. 11 is an explanatory diagram showing a cross-sectional configuration of the single cell 140a in the second embodiment. FIG. 11A shows a C1-C1 cross section of FIG. 3B, and FIG. 11B shows a D1-D1 cross section of FIG. 3B. The configuration of the single cell 140a of the second embodiment is different from the configuration of the single cell 140 of the first embodiment shown in FIG. Is the same as the configuration of the single cell 140 of the first embodiment.

  As shown in FIG. 11, in the single cell 140a of the second embodiment, the length of the anode-side porous channel layer 220a is longer than the length of each of the other anode-side layers (the anode 214 and the anode-side diffusion layer 216). The length is shortened by approximately L2. More specifically, the length of the anode-side porous channel layer 220a is substantially the same as the length of each layer on the cathode side. Hereinafter, a portion where the anode-side porous flow path layer 220a is shorter than the anode-side diffusion layer 216 is referred to as an anode-side porous flow path layer shortened portion.

  FIG. 12 is an explanatory view schematically showing the shape of the region facing the anode-side porous channel layer shortened portion in the anode-side separator 310a of the second embodiment. As shown in FIGS. 11 and 12, ribs 386 and a plurality of convex portions 382 and 384 are formed in a region facing the anode side porous body flow path layer shortened portion of the anode side separator 310a. The ribs 386 are formed in a continuous convex shape (convex shape convex toward the cathode separator 320 side) extending along a direction (X direction) parallel to the long side of the plane of the power generation module 200. The position of the rib 386 is substantially the same as the position of the outer edge of the anode side diffusion layer 216. The convex portions 382 and 384 are discretely arranged on the anode-side porous body flow path layer shortened portion in the anode-side separator 310a, and are formed in a convex shape toward the cathode-side separator 320 side. The plurality of convex portions 382 are arranged side by side in the vicinity of the outer edge of the anode-side porous channel layer 220a. Further, the plurality of convex portions 384 are arranged side by side along a substantially intermediate line between the line of the rib 386 and the line where the plurality of convex portions 382 are arranged. The innermost surface along the stacking direction of the ribs 386 and the convex portions 382 and 384 is in contact with the surface of the anode side diffusion layer 216.

  In the single cell 140a of the second embodiment, 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 310a, and the parallel portion of the oxidant gas side folded portion 325. And the electrolyte membrane 212 are sealed with a sealing material 420.

  In the single cell 140a of the second embodiment, due to the presence of the rib 386, the sealing material 420 disposed between the parallel portion of the oxidant gas side folded portion 325 and the convex portion 315 and the electrolyte membrane 212 faces inward in the plane direction. Is prevented from moving. Therefore, in the vicinity of the folded portion 325 formed adjacent to the oxidant gas supply manifold 152, the power generation module 200 has a width of approximately L2 between the outer edge of the anode-side porous channel layer 220a and the rib 386. A groove-type internal channel space CR extending in a direction parallel to the long side of the flat surface is secured. Although not shown in FIG. 11, a groove-type internal flow path space CR is similarly secured in the vicinity of the folded portion 325 formed adjacent to the oxidant gas discharge manifold 154.

  The groove-type internal channel space CR is formed between the parallel part of the folded part 322 of the cathode side separator 320 and the part of the cathode side separator 320 facing the parallel part of the folded part 322 along the stacking direction. It communicates with the internal flow path space 350 (see FIG. 5). Accordingly, in the fuel cell 100 of the second embodiment, as in the first embodiment, hydrogen as the fuel gas supplied to the fuel gas supply manifold 162 is communicated with the communication hole 326 formed in the oxidant gas side folded portion 325. Is guided to the internal channel space 350, enters the groove-type internal channel space CR, and passes through the groove-type internal channel space CR in a direction (X direction) parallel to the long side of the plane of the power generation module 200. It enters the anode-side porous channel layer 220a while diffusing along. The fuel gas moves from the groove-type internal channel space CR to the anode-side porous channel layer 220a through the gap between the projections 382 and 382 (see FIG. 12). Thereafter, the fuel gas is supplied to the anode-side diffusion layer 216 and the anode 214 while flowing in the anode-side porous channel layer 220a toward the discharge side. The fuel gas that has not been used in the power generation module 200 is discharged into the groove-type internal flow path space CR on the downstream side, and the internal flow path formed on the fuel gas discharge manifold 164 side through the groove-type internal flow path space CR. It is guided to the space 350 and further discharged to the fuel gas discharge manifold 164 through a communication hole 326 formed in the fuel gas discharge manifold 164.

  As described above, in the fuel cell 100 of the second embodiment, the length of the anode-side porous flow path layer 220a is shorter than the length of the anode-side diffusion layer 216 by approximately the length L2, and the anode-side porous A groove-type internal channel space CR is formed in the body channel layer shortened portion. Further, since the rib 386 is formed on the anode side separator 310a, the seal member 420 disposed between the cathode side separator 320 and the anode side separator 310a is prevented from moving inward in the surface direction. Therefore, a groove-type internal flow path space CR is secured at the upstream and downstream outer edges of the anode-side porous flow path layer 220a in the fuel gas flow direction. Therefore, in the fuel cell 100 of the second embodiment, a so-called common rail can be formed inside the single cell 140a so as to improve the uniform distribution of the fuel gas. The thickness of the single cell 140a is not increased compared to the case where the flow path space is provided. Therefore, in the fuel cell 100 of the second embodiment, the uniform distribution of the reaction gas can be improved while reducing the thickness of the single cell 140a.

  Further, in the fuel cell 100 of the second embodiment, a portion where the length of the anode-side porous channel layer 220a is shorter than the length of the anode-side diffusion layer 216 can be used as the groove-type internal channel space CR. Therefore, the uniform distribution of the reaction gas can be improved while suppressing an increase in the size of the single cell 140a.

  Further, in the fuel cell 100 of the second embodiment, since the convex portions 382 and 384 are formed on the anode side separator 310a, the anode side diffusion layer 216 is also supported by the convex portions 382 and 384, and the anode side separator 310a and A groove-type internal channel space CR is ensured between the anode-side diffusion layer 216 and the anode-side diffusion layer 216. Further, since the plurality of convex portions 382 are arranged in the vicinity of the outer edge of the anode-side porous channel layer 220a, as a positioning reference when the anode-side porous channel layer 220a is arranged on the anode-side separator 310a. It can be used, and the manufacturing process of the single cell 140a can be facilitated and the accuracy can be improved.

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 groove-type internal channel space CR is formed along the upstream and downstream outer edges of the anode-side porous channel layer 220 in the reaction gas flow direction. The passage space CR may be formed along the outer edge of only one of the upstream side and the downstream side in the reaction gas flow direction in the anode-side porous channel layer 220.

  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. .

  In the above embodiments, the power generation module 200 includes the anode side diffusion layer 216 and the cathode side diffusion layer 217. However, the power generation module 200 includes one or both of the anode side diffusion layer 216 and the cathode side diffusion layer 217. May not be included.

  Further, in each of the above embodiments, a part of the cathode separator 320 is folded to form the fuel gas side folded portion 322 and the oxidant gas side folded portion 325, thereby ensuring a gas flow path and a gas seal in the reaction gas lead-in / out portion. However, the fuel gas side folded portion 322 and the oxidant gas side folded portion 325 are not formed, and a reaction frame such as a resin frame or a resin film provided with a reaction gas passage space is provided. It is good also as what implement | achieves coexistence with ensuring of the gas flow path in the reaction gas inflow / outflow part and ensuring of gas-seal property, using components as a part of separator. Also in this case, a communication hole for communicating each manifold and the internal flow path space is provided in another part such as a resin frame or a resin film, and a rib is provided at the boundary between the separator between the separator and the groove type internal flow path space CR. What is necessary is just to provide.

  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-described embodiments, the groove-type internal channel space CR that communicates with the end surface of the anode-side porous channel layer 220 is provided. A groove-type internal channel space CR that communicates with the end face of the layer 230 may be provided.

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

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 319 ... Dimple 320 ... Cathode side separator 321 ... Opening 322 ... Fuel gas side return part 323 ... Opening 324 ... convex part 325 ... oxidant gas side folded part 326 ... communication hole 327 ... convex part 329 ... convex part 336 ... convex part 350 ... internal flow path space 360 ... internal flow path space 372 ... rib 382 ... convex part 384 ... convex part 386 ... Rib 420 ... Sealing material 500 ... Gasket 502 ... Projection

Claims (5)

A fuel cell,
A plurality of stacked fuel cells; and
A plurality of reaction gas passages that are substantially parallel to the stacking direction of the fuel cells and circulate the reaction gas used in each of the fuel cells, and
Each of the fuel cells is
A membrane electrode assembly comprising an electrolyte membrane and electrode layers disposed on both sides of the electrolyte membrane;
A pair of porous channel layers formed of a porous material and disposed so as to sandwich the membrane electrode assembly;
A first separator and a second separator formed by processing a metal plate and disposed so as to sandwich the pair of porous channel layers,
The first and second separators have openings constituting the reaction gas flow channel at positions outside the surface direction from positions facing the membrane electrode assembly and the porous flow channel layer,
The first separator communicates with an end surface of the reaction gas channel for the reaction gas used in the electrode layer on the first separator side and an end surface of the porous channel layer on the first separator side. A first communication hole communicating with one internal flow path space, the reaction gas flow path for the reaction gas used in the electrode layer on the second separator side, and the porosity on the second separator side. A second communication hole that communicates with a second internal flow path space that communicates with a groove-type internal flow path space that extends along at least one outer edge on the upstream side and the downstream side in the reaction gas flow direction in the body flow path layer; Have
At least one of the first and second separators is located at a position of a boundary between the seal portion that seals between the first and second separators and the groove-type internal flow space, and the groove-type internal flow space. A fuel cell having ribs extending along. The fuel cell according to claim 1,
The first separator has at least a part of the metal plate at a position where the opening constituting the reaction gas flow path for the reaction gas used in the electrode layer on the first separator side is formed. A first folded portion formed by folding the side of the opening on the membrane electrode assembly side as a folding line to the membrane electrode assembly side, and a reactive gas used in the electrode layer on the second separator side At least a part of the metal plate at a position where the opening constituting the reaction gas flow path is formed is formed by folding the side of the opening on the membrane electrode assembly side to the membrane electrode assembly side. A second folded portion,
The first internal channel space is formed between the first folded portion and the first separator,
The second internal channel space is formed between the second folded portion and the first separator,
The first communication hole is formed in the first folded portion,
The second communication hole is a fuel cell formed in the second folded portion. The fuel cell according to claim 1 or 2, wherein
Each fuel cell further comprises:
In each of the first separator side and the second separator side, including a diffusion layer disposed between the electrode layer and the porous channel layer,
The length of the porous channel layer on the second separator side is such that at least the position of the outer edge on the upstream side and the downstream side in the reaction gas flow direction in the porous channel layer is the length on the second separator side. Shorter than the length of the diffusion layer,
The groove-type internal flow path space is a fuel cell, which is a space formed between the second separator and the diffusion layer on the second separator side. The fuel cell according to claim 3, wherein
The second separator has a plurality of convex portions protruding in the direction of the membrane electrode assembly at a portion facing the groove-type internal flow path space. The fuel cell according to claim 4, wherein
At least one of the plurality of convex portions is a fuel cell arranged near an outer edge of the porous channel layer on the second separator side.

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