JP5857817B2 - Fuel cell - Google Patents

Description

  The present invention relates to a fuel cell.

  In recent years, in response to social demands and trends against the background of energy and environmental problems, fuel cells that can operate at room temperature and obtain high output density have attracted attention as power sources for electric vehicles and stationary power sources. A fuel cell is a clean power generation system in which the product of an electrode reaction is water in principle and has almost no adverse effect on the global environment. In particular, a polymer electrolyte fuel cell (PEFC) is expected as a power source for electric vehicles because it operates at a relatively low temperature. The polymer electrolyte fuel cell has a structure in which a plurality of single cells that exhibit a power generation function are stacked. This single cell includes a polymer-electrolyte membrane, a membrane-electrode assembly (MEA) having a pair of catalyst layers and a pair of gas diffusion layers (GDL) that are sequentially formed on both surfaces of the membrane. And MEA which each single cell has is electrically connected with MEA of an adjacent single cell through a separator. Thus, a fuel cell stack is comprised by laminating | stacking a single cell. The fuel cell stack functions as power generation means that can be used for various applications.

  In such a fuel cell stack, the separator exhibits a function of electrically connecting adjacent single cells as described above. In addition to this, a gas flow path is usually provided on the surface of the separator facing the MEA. The gas flow path functions as gas supply means for supplying fuel gas and oxidant gas to the anode and the cathode, respectively.

  Here, the power generation mechanism of the PEFC will be briefly described. During operation of the PEFC, fuel gas (for example, hydrogen gas) is supplied to the anode side of the single cell, and oxidant gas (for example, atmospheric air, oxygen) is supplied to the cathode side. Supplied. As a result, in each of the anode and the cathode, an electrochemical reaction represented by the following reaction formula proceeds to generate electricity.

Anode reaction: H ₂ → 2H ⁺ + 2e ⁻ (1)
Cathode reaction: 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O (2)
In order to advance the electrochemical reaction, GDL requires a gas supply function that efficiently diffuses fuel gas and oxidant gas and supplies them to the catalyst layer, and various proposals have been made. For example, Patent Document 1 reports a fuel cell in which an electrode member that forms a gas diffusion space is disposed between a catalyst layer and a separator instead of GDL. The electrode member is composed of a conductive fabric in which a plurality of fine grooves are formed in parallel. When viewed in a cross section in a direction perpendicular to the direction in which the grooves extend, apexes for forming the grooves appear regularly and continuously in the fabric. As a result, the gas diffusion space is made uniform or regular, the pressure loss in the gas diffusion space is reduced, and a sufficient gas supply function is ensured.

JP 2011-48936 A

  Although the fuel cell disclosed in Patent Document 1 has a sufficient gas supply function, it is required to further reduce the electrical resistance in order to improve the efficiency of the fuel cell. Furthermore, it is also required that the electrode member can maintain the gas diffusion space against the compressive load acting in the stacking direction when configuring the fuel cell.

  Therefore, an object of the present invention is to provide a fuel cell that can reduce electric resistance and further has excellent gas diffusibility by maintaining a gas diffusion space against a compressive load. .

  In order to achieve the above object, a fuel cell of the present invention comprises a polymer electrolyte membrane, a cathode catalyst layer disposed on one side of the polymer electrolyte membrane, and an anode disposed on the other side of the polymer electrolyte membrane. And a catalyst layer. In addition, the fuel cell of the present invention has a cathode separator and an anode separator that have conductivity and block gas. An electrode member made of a conductive porous substrate is disposed between at least one of the cathode catalyst layer and the cathode separator and between the anode catalyst layer and the anode separator. The electrode member has a planar portion that is in surface contact with the catalyst layer, and a plurality of support portions that are provided on the planar portion and support the separator to form a gas diffusion space, and the plurality of support portions are arranged in a scattered manner. Having a dotted shape.

  In the fuel cell of the present invention, since the electrode member is in surface contact with the catalyst layer at the flat portion, the electrode member and the catalyst layer are in good contact with each other, so that electric resistance can be reduced. Furthermore, since the compressive load is dispersed by the plurality of support portions arranged in the form of dots and the support portion is supported by the flat portion, the deformation of the support portion due to the compressive load and the burying in the catalyst layer are suppressed, and gas diffusion Since the working space is maintained, gas diffusibility is excellent.

It is sectional drawing which shows schematically the basic composition of the fuel cell of embodiment. It is a partial expanded sectional view which follows the 2-2 line of FIG. It is a top view which shows the electrode member of embodiment schematically. It is a top view which shows the example of the electrode member different from embodiment schematically. It is a top view which shows roughly the other example of the electrode member different from embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and is different from an actual ratio.

  As shown in FIG. 1, a fuel cell 10 according to an embodiment includes a polymer electrolyte membrane 11 formed of a polymer electrolyte, a cathode catalyst layer 13 disposed on one side of the polymer electrolyte membrane 11, a polymer An anode catalyst layer 12 disposed on the other side of the electrolyte membrane 11. In addition, the fuel cell 10 includes a cathode separator 16 disposed to face the cathode catalyst layer 13 and an anode separator 15 disposed to face the anode catalyst layer 12.

  A cathode electrode member 18 made of a conductive porous substrate is disposed between the cathode catalyst layer 13 and the cathode separator 16. An anode electrode member 17 made of a conductive porous substrate is disposed between the anode catalyst layer 12 and the anode separator 15.

  The above laminated components are held by receiving a compressive load from a pair of end plates (not shown) that sandwich them from the lamination direction. Further, a gas seal may be disposed between the cathode separator 16 and the polymer electrolyte membrane 11 and between the anode separator 15 and the polymer electrolyte membrane 11, but the illustration is omitted in FIG. 1.

(Polymer electrolyte membrane 11)
The polymer electrolyte membrane 11 has a function of selectively allowing protons generated in the anode catalyst layer 12 during the operation of the fuel cell 10 to permeate the cathode catalyst layer 13. Further, the polymer electrolyte membrane 11 has a function as a partition wall for preventing the fuel gas supplied to the anode side and the oxidant gas supplied to the cathode side from being mixed. The polymer electrolyte membrane 11, the anode catalyst layer 12, the anode electrode member 17, the cathode catalyst layer 13, and the cathode electrode member 18 are laminated to constitute a membrane electrode assembly 14 (MEA).

  The polymer electrolyte membrane 11 is not particularly limited, and a membrane made of a conventionally known polymer electrolyte in the technical field of the fuel cell 10 can be appropriately employed. The polymer electrolyte used for the polymer electrolyte membrane 11 and the polymer electrolyte used for each catalyst layer may be the same or different, but the adhesion between each catalyst layer and the polymer electrolyte membrane 11 From the viewpoint of improving the above, it is preferable to use the same one.

  The thickness of the polymer electrolyte membrane 11 may be appropriately determined in consideration of the characteristics of the membrane electrode assembly 14 to be obtained.

(Anode catalyst layer 12, cathode catalyst layer 13)
The anode catalyst layer 12 and the cathode catalyst layer 13 are layers in which the cell reaction actually proceeds. Specifically, a hydrogen oxidation reaction proceeds in the anode catalyst layer 12, while an oxygen reduction reaction proceeds in the cathode catalyst layer 13. The anode catalyst layer 12 and the cathode catalyst layer 13 each include a catalyst component, a conductive catalyst carrier that supports the catalyst component, and a polymer electrolyte.

  The catalyst component used for the cathode catalyst layer 13 is not particularly limited as long as it has a catalytic action in the oxygen reduction reaction, and a known catalyst can be used in the same manner. Further, the catalyst component used in the anode catalyst layer 12 is not particularly limited as long as it has a catalytic action in the oxidation reaction of hydrogen, and a known catalyst can be used in the same manner.

  The catalyst particles are supported on a conductive carrier and become an electrode catalyst. Here, any conductive carrier may be used as long as it has a specific surface area for supporting the catalyst particles in a desired dispersed state and has sufficient electronic conductivity as a current collector.

  The anode catalyst layer 12 and the cathode catalyst layer 13 contain a polymer electrolyte in addition to the electrode catalyst. Here, the polymer electrolyte is not particularly limited, and a known one can be used.

(Anode separator 15 and cathode separator 16)
The anode separator 15 and the cathode separator 16 have conductivity, and have a function of electrically connecting the fuel cells 10 when a plurality of fuel cells 10 are connected in series to form a fuel cell stack. . In addition, the anode separator 15 and the cathode separator 16 also have a function as a partition that blocks the fuel gas, the oxidant gas, and the coolant from each other.

  As materials constituting the anode separator 15 and the cathode separator 16, conventionally known materials such as dense carbon graphite, carbon such as a carbon plate, and metals such as stainless steel can be appropriately used.

(Anode electrode member 17, cathode electrode member 18)
As shown in FIG. 2, the anode electrode member 17 includes a planar portion 170 that is in surface contact with the anode catalyst layer 12 and a plurality of support portions that are provided on the planar portion 170 and support the anode separator 15 to form a gas diffusion space. 171. As shown in FIG. 3, the anode electrode member 17 has a dot shape in which a plurality of support portions 171 are arranged in a dotted pattern.

  The support portion 171 has an emboss shape that is recessed with respect to one surface of the flat portion 170 and protrudes with respect to the other surface of the flat portion 170. The support portion 171 has a cylindrical shape. The distance between the support part 171 and the support part 171, the outer diameter of the support part 171, the height of the support part 171, and the like are not particularly limited, and desired effects such as an improvement in strength and an improvement in gas diffusibility are obtained. It can be determined as appropriate in consideration.

  The support portion 171 ensures electrical conductivity with the anode separator 15 by directly contacting the anode separator 15. A space between the support portion 171 and the support portion 171 is a gas diffusion space through which the fuel gas flows. The fuel gas flows into a gas diffusion space between the support portion 171 and the support portion 171 from a manifold (not shown) through which the fuel gas formed in the anode separator 15 flows. Then, the fuel gas is supplied to the anode catalyst layer 12 through the holes of the conductive porous substrate that forms the flat portion 170. As shown in FIG. 3, the plurality of support portions 171 are arranged in a staggered manner with respect to the flow direction F <b> 1 of the fuel gas that moves in the gas diffusion space. That is, the plurality of support portions 171 are arranged so that the positions of the support portions 171 in the direction intersecting the fuel gas flow direction F1 are alternately shifted along the fuel gas flow direction F1.

  The flat portion 170 is in contact with the anode catalyst layer 12 to ensure conductivity between the anode catalyst layer 12. The flat portion 170 is disposed so as to cover the entire surface of the anode catalyst layer 12, but the flat portion 170 and the anode catalyst layer 12 do not contact at the opening 172 in the embossed depression of the support portion 171. Accordingly, the diameter φ1 of the opening 172 is preferably smaller from the viewpoint of reducing the contact resistance by increasing the contact area between the flat portion 170 and the anode catalyst layer 12. The diameter φ1 of the opening 172 is preferably 0.5 mm or less. The outer diameter of the support portion 171 is substantially equal to the diameter φ1 of the opening 172.

  As shown in FIG. 2, the cathode electrode member 18 includes a flat portion 180 that is in surface contact with the cathode catalyst layer 13 and a plurality of support portions that are provided on the flat portion 180 and support the cathode separator 16 to form a gas diffusion space. 181. As shown in FIG. 3, the cathode electrode member 18 has a dot shape in which a plurality of support portions 181 are arranged in a dotted pattern.

  The support portion 181 has an emboss shape that is recessed with respect to one surface of the flat portion 180 and protrudes with respect to the other surface of the flat portion 180. Moreover, the support part 181 has a cylindrical shape. The distance between the support portion 181 and the support portion 181, the outer diameter of the support portion 181, the height of the support portion 181, and the like are not particularly limited, and desired effects such as improvement in strength and improvement in gas diffusibility are obtained. It can be determined as appropriate in consideration.

  The support portion 181 ensures electrical conductivity with the cathode separator 16 by directly contacting the cathode separator 16. A space between the support portion 181 and the support portion 181 is a gas diffusion space through which the oxidant gas flows. The oxidant gas flows into a gas diffusion space between the support part 181 and the support part 181 from a manifold (not shown) through which the oxidant gas formed in the cathode separator 16 flows. Then, the oxidant gas is supplied to the cathode catalyst layer 13 through the holes of the conductive porous substrate that forms the flat portion 180. As shown in FIG. 3, the plurality of support portions 181 are arranged in a staggered manner with respect to the flow direction F2 of the oxidant gas that moves in the gas diffusion space. That is, the plurality of support portions 181 are arranged so that the positions of the support portions 181 in the direction intersecting the flow direction F2 of the oxidant gas are alternately shifted along the flow direction F2 of the oxidant gas.

  The flat portion 180 is in contact with the cathode catalyst layer 13 and ensures electrical conductivity with the cathode catalyst layer 13. The flat portion 180 is disposed so as to cover the entire surface of the cathode catalyst layer 13, but the flat portion 180 and the cathode catalyst layer 13 are not in contact with each other at the opening 182 in the embossed depression of the support portion 181. Therefore, the diameter φ2 of the opening 182 is preferably smaller from the viewpoint of reducing the contact resistance by increasing the contact area between the flat portion 180 and the cathode catalyst layer 13. The diameter φ2 of the opening 182 is preferably 0.5 mm or less. The outer diameter of the support portion 181 is substantially equal to the diameter φ2 of the opening 182.

The support part 171 and the support part 181 are preferably positioned so as to substantially overlap each other via the polymer electrolyte membrane 11, the anode catalyst layer 12, and the cathode catalyst layer 13 in the thickness direction (substantially the same position). The conductive porous base material forming the anode electrode member 17 and the cathode electrode member 18 is a wire mesh. For example, the support portion 171 is integrally formed with the flat portion 170 by embossing a sheet-like wire mesh. Similarly, the embossing is performed on the sheet-shaped wire net, so that the support portion 181 is formed integrally with the flat portion 180.

  The dimensions of the metal mesh that forms the anode electrode member 17 and the cathode electrode member 18 are not particularly limited, and can be appropriately determined in consideration of desired effects such as a reduction in electrical resistance and an improvement in gas diffusibility. For example, the number of meshes of the wire mesh is preferably 100 mesh or more, and more preferably 100 to 500 mesh. With such a numerical aperture, it is easy to supply the fuel gas to the anode catalyst layer 12 through the flat portion 170 and supply the oxidant gas to the cathode catalyst layer 13 through the flat portion 180. Moreover, it is preferable that the wire diameter which comprises a metal-mesh is 25-110 micrometers. With such a wire diameter, the contact area between the anode catalyst layer 12 and the anode electrode member 17 per unit area and the contact area between the cathode catalyst layer 13 and the cathode electrode member 18 per unit area increase. Moreover, it is preferable that the pitch of a wire mesh is 50-260 micrometers. The weaving method of the wire mesh is not particularly limited, and any of plain weave, twill, plain tatami, twill, etc. The mesh between the interlaced wires in the wire mesh corresponds to the pores in the conductive porous substrate. The number of meshes and the wire diameter can be measured according to JIS G3555.

  The conductive material forming the anode electrode member 17 and the cathode electrode member 18 is not particularly limited. Specifically, the anode electrode member 17 and the cathode electrode member 18 are preferably made of metal or coated on the surface with metal. Here, although it does not restrict | limit especially as a metal, What is used as a constituent material of a metal separator is used suitably. For example, iron, titanium, aluminum, and alloys thereof can be used. These materials are preferably used from the viewpoints of mechanical strength, versatility, cost performance, ease of processing, and the like. Here, the iron alloy includes stainless steel. Especially, it is preferable that the anode electrode member 17 and the cathode electrode member 18 are comprised from stainless steel, aluminum, or aluminum alloy. Moreover, the metal in particular when using what coat | covered the surface with the metal as the anode electrode member 17 and the cathode electrode member 18 is not restrict | limited, The material similar to having mentioned above can be used. In addition, the substrate on which the surface is coated is not particularly limited, but preferably has conductivity. For example, a conductive polymer material or a conductive carbon material can be used.

  Conductive anticorrosion treatment may be performed on the surfaces of the anode electrode member 17 and the cathode electrode member 18. Due to the conductive anticorrosion treatment, the corrosion of the anode electrode member 17 and the cathode electrode member 18 can be suppressed / prevented under the environment in the fuel cell 10 and the durability can be improved.

  The conductive anticorrosion treatment is preferably a gold or conductive carbon coating. Gold plating can be used as the gold coating. Further, as the gold coating, a gold clad in which gold is bonded to the surface can be used. Further, as the conductive carbon coating, it is preferable to provide a conductive carbon layer on the surface. The conductive carbon constituting the conductive carbon layer is not particularly limited, and for example, carbon black, graphite, fullerene, carbon nanotube, carbon nanofiber, carbon nanohorn, carbon fibril, and the like can be used. Specific examples of carbon black include ketjen black, acetylene black, channel black, lamp black, oil furnace black, and thermal black. Carbon black may be subjected to a graphitization treatment. The said carbon material may be used independently or may use 2 or more types together.

  Further, the water repellent treatment may be applied to the anode electrode member 17 and the cathode electrode member 18. The water repellent treatment reduces the retention of water between the anode electrode member 17 and the anode separator 15 and between the cathode electrode member 18 and the cathode separator 16, and as a result, inhibition of gas supply by water is suppressed. The In addition, by suppressing the flooding of water, the gas can be supplied to the anode catalyst layer 12 and the cathode catalyst layer 13 without stagnation. As a result, it is possible to suppress a sudden drop in voltage and stabilize the voltage. As the water repellent treatment, there are a method in which the anode electrode member 17 and the cathode electrode member 18 are coated with a water repellent, and a method in which the conductive carbon layer contains a water repellent.

  Further, hydrophilic treatment may be applied to the anode electrode member 17 and the cathode electrode member 18 instead of the water repellent treatment. By the hydrophilic treatment, liquid water from the anode catalyst layer 12 and the cathode catalyst layer 13 is drawn to the gas diffusion space side, so that water clogging in the anode catalyst layer 12 and the cathode catalyst layer 13 can be reduced. As a result, it is possible to suppress a sudden drop in voltage and stabilize the voltage. As the hydrophilic treatment, there are a method in which the anode electrode member 17 and the cathode electrode member 18 are coated with a hydrophilic agent, and a method in which the conductive carbon layer contains a hydrophilic agent.

  The manufacturing method of the fuel cell 10 is not particularly limited, and conventionally known knowledge in the field of the fuel cell 10 can be appropriately referred to. The fuel used when operating the fuel cell 10 is not particularly limited.

  Furthermore, a fuel cell stack in which a plurality of membrane electrode assemblies 14 are stacked via an anode separator 15 and a cathode separator 16 may be configured so that the fuel cell 10 can exhibit a desired voltage. The shape of the fuel cell 10 is not particularly limited, and may be determined as appropriate so that desired battery characteristics such as voltage can be obtained.

  The effect of this embodiment is described.

  In the fuel cell 10 of the present embodiment, since the anode electrode member 17 is in surface contact with the anode catalyst layer 12 at the flat portion 170, the anode electrode member 17 and the anode catalyst layer 12 are in good contact with each other. The power generation efficiency of the battery 10 can be improved. In addition, since the cathode electrode member 18 is in surface contact with the cathode catalyst layer 13 at the flat portion 180, the cathode electrode member 18 and the cathode catalyst layer 13 are in good contact with each other, so that electric resistance can be reduced, and thus power generation efficiency of the fuel cell 10 can be improved. It can be planned.

  Further, the compressive load acting in the stacking direction is dispersed by the plurality of support portions 171, and the support portion 171 is supported by the flat portion 170. For this reason, the deformation of the support portion 171 due to the compressive load and the burying in the anode catalyst layer 12 are suppressed and the gas diffusion space is maintained, so that the gas diffusibility of the fuel gas is excellent. Further, the compressive load acting in the stacking direction is dispersed by the plurality of support portions 181, and the support portion 181 is supported by the flat portion 180. For this reason, the deformation of the support portion 181 due to the compressive load and the burying in the cathode catalyst layer 13 are suppressed and the gas diffusion space is maintained, so that the gas diffusibility of the oxidant gas is excellent.

  Further, the bending moment generated in the support portion 171 due to the pressure from the anode separator 15 is alleviated by arranging the support portions 171 in the form of dots. For this reason, the support portion 171 is unlikely to be deformed so that the opening 172 expands, and as a result, a reduction in the contact area between the anode electrode member 17 and the anode catalyst layer 12 is suppressed. Therefore, the power generation efficiency of the fuel cell 10 is good. Further, the bending moment generated in the support portion 181 due to the pressure from the cathode separator 16 is alleviated by arranging the support portions 181 in the form of dots. For this reason, the support portion 181 is unlikely to deform so that the opening 182 is widened, and as a result, a reduction in the contact area between the cathode electrode member 18 and the cathode catalyst layer 13 is suppressed. Therefore, the power generation efficiency of the fuel cell 10 is good.

  Further, since the flat portion 170 is formed of the conductive porous substrate, the fuel gas is easily supplied to the anode catalyst layer 12 through a large number of holes. Further, since the flat portion 180 is formed of the conductive porous substrate, the oxidant gas is easily supplied to the cathode catalyst layer 13 through a large number of holes. In addition, since the conductive porous substrate is a wire mesh, the opening ratio of the flat portion 170 and the flat portion 180 is large and the wall thickness is thin compared to other conductive porous substrates such as punching metal. Accordingly, the fuel gas can easily reach the anode catalyst layer 12 through the flat portion 170, and the oxidant gas can easily reach the cathode catalyst layer 13 through the flat portion 180, so that power generation efficiency can be improved.

  In addition, since the flat portion 170 and the support portion 171 are integrally formed, compared with the case where the flat portion 170 and the support portion 171 are separately formed and then combined, the present embodiment saves the trouble of combining the two. So you can keep costs down. In addition, since the flat surface portion 180 and the support portion 181 are integrally formed, compared to the case where the flat surface portion 180 and the support portion 181 are separately formed and then combined with each other, this embodiment saves the trouble of combining the both. So you can keep costs down.

  Further, since the support portion 171 has an embossed shape, the support portion 171 can be easily formed integrally with the flat portion 170 by embossing, so that the cost can be reduced. Further, since the support portion 181 has an embossed shape, the support portion 181 can be easily formed integrally with the flat portion 180 by embossing, so that the cost can be reduced.

  Further, since the plurality of support portions 171 are arranged in a staggered manner with respect to the fuel gas flow direction F1, for example, as shown in FIG. 4, the plurality of support portions 171A are arranged along the gas flow direction F1. Compared with the case where it is made, fuel gas disperse | distributes and it is easy to contact each support part 171. FIG. Therefore, more fuel gas flows into each support portion 171 and remains. Since the fuel gas remaining inside the support portion 171 is likely to reach the anode catalyst layer 12 as compared with the case of flowing, the power generation efficiency of the fuel cell 10 can be improved. Similarly, since the plurality of support portions 181 are arranged in a staggered manner with respect to the flow direction F2 of the oxidant gas, the oxidant gas is easily dispersed and stays in each support portion 181. Therefore, the fuel cell 10 The power generation efficiency can be improved.

  Unlike the present embodiment, for example, as shown in FIG. 5, when the support portion 171 </ b> B having a prismatic shape is provided on the plane portion 170, stress concentration may occur at the corner of the support portion 171 </ b> B due to the compressive load. On the other hand, in the present embodiment, the support portion 171 has a columnar shape, and therefore the outer periphery has an arc shape, so that stress concentration hardly occurs. Therefore, damage to the polymer electrolyte membrane 11 can be prevented. The same applies to the support portion 181. Since the support portion 181 has a cylindrical shape, stress concentration is unlikely to occur, and therefore the damage of the polymer electrolyte membrane 11 can be prevented.

  Moreover, since the diameter φ1 of the opening 172 is 0.5 mm or less, the area of the flat portion 170 that does not come into contact with the anode catalyst layer 12 can be reduced. Therefore, the electric resistance can be reduced, and the power generation efficiency of the fuel cell 10 can be improved. Moreover, since the diameter φ2 of the opening 182 is 0.5 mm or less, the area of the flat portion 180 that does not come into contact with the cathode catalyst layer 13 can be reduced. Therefore, the electric resistance can be reduced, and the power generation efficiency of the fuel cell 10 can be improved.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, in the above embodiment, the conductive porous base material forming the anode electrode member 17 and the cathode electrode member 18 is a wire mesh, but the present invention is not limited to this. For example, the conductive porous substrate may be a punching metal, an etching metal, an expanded metal, or the like.

  In the above embodiment, the anode electrode member 17 is disposed between the anode catalyst layer 12 and the anode separator 15, and the cathode electrode member 18 is disposed between the cathode catalyst layer 13 and the cathode separator 16. It is not limited to this. That is, one of the anode electrode member 17 and the cathode electrode member 18 may be a known electrode member.

  Moreover, in the said embodiment, although a metal mesh is embossed and the support part and the plane part are integrally formed from the metal mesh, this invention is not limited to this. That is, the support part and the plane part may be formed separately, and then the support part may be fixed on the plane part.

  Moreover, a some support part may be provided by arrangement | positioning different from zigzag form, for example like FIG.

  In addition, the shape of the opening in the embossed depression of the support portion is not limited to a circular shape like the openings 172 and 182 of the above embodiment, and may be an elliptical shape. In this case, the width of the widest portion in the opening, that is, the major axis is preferably 0.5 mm or less.

  Further, the support portion may have a prismatic shape as shown in FIG. 5, for example. In this case, the shape of the opening in the embossed depression of the support portion is a rectangular shape, and the width of the widest portion in the opening, that is, the length of the diagonal line is preferably 0.5 mm or less. is there.

10 Fuel cell,
11 Polymer electrolyte membrane,
12 anode catalyst layer,
13 cathode catalyst layer,
14 membrane electrode assembly,
15 anode separator,
16 cathode separator,
17 Anode electrode member (electrode member),
18 Cathode electrode member (electrode member),
170, 180 plane part,
171, 171A, 171B support part,
181, 181A, 181B support part,
172, 182 openings.

Claims (7)

A polymer electrolyte membrane;
A cathode catalyst layer disposed on one side of the polymer electrolyte membrane and a cathode separator having conductivity and blocking gas;
An anode catalyst layer disposed on the other side of the polymer electrolyte membrane and an anode separator having conductivity and blocking gas;
An electrode member disposed between at least one of the cathode catalyst layer and the cathode separator and between the anode catalyst layer and the anode separator and made of a conductive porous substrate;
The electrode member includes a flat portion that is in surface contact with the catalyst layer, and a plurality of support portions that are provided on the flat portion and support the separator to form a gas diffusion space, and the plurality of support portions include A fuel cell having dot shapes arranged in a dotted pattern.   The fuel cell according to claim 1, wherein the electrode member has the planar portion and the support portion formed integrally.   The fuel cell according to claim 2, wherein the support portion has an embossed shape that is recessed with respect to one surface of the planar portion and protrudes with respect to the other surface of the planar portion.   The plurality of support portions are arranged in a zigzag pattern in which the positions of the support portions in the direction intersecting the gas flow direction are alternately shifted along the gas flow direction moving through the gas diffusion space. The fuel cell according to any one of claims 1 to 3.   The fuel cell according to any one of claims 1 to 4, wherein the conductive porous substrate is made of a wire mesh.   The fuel cell according to any one of claims 1 to 5, wherein the support portion has a cylindrical shape.   The fuel cell according to claim 3, wherein the opening in the embossed recess has a width of 0.5 mm or less at the widest portion.

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