JP2005190710A - Fuel cell - Google Patents

Abstract

A fluid such as a reaction gas can be smoothly and uniformly supplied along a plane of a separator, and good power generation performance can be obtained with a small and simple configuration.
A power generation cell (12) includes an electrolyte membrane / electrode structure (14) and first and second metal separators (16, 18). A plurality of embossed portions 42 projecting toward the cathode side electrode 28 are provided on the surface 16 a of the first metal separator 16. A plurality of embossed portions 42 a having a larger diameter than the embossed portion 42 are provided in the central portion of the surface 16 a of the first metal separator 16.
[Selection] Figure 1

Description

  The present invention relates to a fuel cell in which an electrolyte / electrode structure provided with electrodes on both sides of an electrolyte and metal separators are alternately stacked, and at least a reaction gas communication hole is formed through the stacking direction.

  For example, a polymer electrolyte fuel cell employs an electrolyte membrane (electrolyte) made of a polymer ion exchange membrane. In this fuel cell, an electrolyte membrane / electrode structure constituted by an anode catalyst and a cathode electrode each made of an electrode catalyst and porous carbon is sandwiched between separators (bipolar plates) on both sides of the electrolyte membrane. It has a power generation cell constituted by doing. Usually, a fuel cell stack in which a predetermined number of the power generation cells are stacked is used.

  In this type of fuel cell, a fuel gas (reactive gas) supplied to the anode electrode, for example, a gas mainly containing hydrogen (hereinafter also referred to as a hydrogen-containing gas) is hydrogen ionized on the electrode catalyst, It moves to the cathode side electrode side through the electrolyte membrane. Electrons generated during that time are taken out to an external circuit and used as direct current electric energy. The cathode side electrode is supplied with an oxidant gas (reaction gas), for example, a gas mainly containing oxygen or air (hereinafter also referred to as oxygen-containing gas). Hydrogen ions, electrons and oxygen react to produce water.

  In the fuel cell described above, a fuel gas flow path for flowing fuel gas to face the anode side electrode and an oxidant gas flow for flowing oxidant gas to face the cathode side electrode in the plane of each separator. Roads are provided. Further, between the separators, a coolant flow path for allowing a coolant to flow as needed is provided along the surface direction of the separator.

  A fuel gas flow channel, an oxidant gas flow channel (hereinafter also referred to simply as a reaction gas flow channel) and a cooling medium flow channel are generally separated from the flow channel inlet penetrating in the stacking direction of the separator toward the flow channel outlet. A plurality of flow channel grooves provided in the plane of the film are provided, and the flow channel grooves are constituted by straight grooves or folded grooves.

  However, when a flow path inlet or flow path outlet with a small opening is provided for a plurality of flow path grooves, fluid such as fuel gas, oxidant gas, or cooling medium is uniformly distributed in the separator surface along the flow path grooves. In order to make it flow in, the buffer part is needed around the flow path inlet and the flow path outlet. Further, in the plurality of parallel flow channel grooves, the generated water tends to stay in the specific flow channel groove, and the discharge efficiency of the generated water may be reduced.

  Therefore, for example, a fuel cell separator disclosed in Patent Document 1 is known. In this patent document 1, as shown in FIG. 11, the separator plate 1 is made of a metal material that can be easily embossed or dimpled. Is formed by embossing or dimple processing.

  For example, a fuel gas inlet 4 a and a fuel gas outlet 4 b are provided at both side edges of the separator plate 1, and an oxidant gas inlet 5 a and an oxidant gas outlet are provided at both upper and lower edges of the separator plate 1. 5b is provided.

  The protrusion 2 protrudes toward the one surface 1a side of the separator plate 1, and a fuel gas passage 6 communicating with the fuel gas inlet 4a and the fuel gas outlet 4b is formed between the protrusions 2. The protrusion 3 protrudes toward the other surface 1b of the separator plate 1, and an oxidant gas passage 7 communicating with the oxidant gas inlet 5a and the oxidant gas outlet 5b is formed between the protrusions 3. Yes.

  In such a configuration, for example, when the fuel gas supplied to the fuel gas inlet 4 a is supplied to one surface 1 a of the separator plate 1, the fuel gas passage 6 formed continuously between the protrusions 2. In addition to being supplied to an electrode (not shown), unused fuel gas is discharged to the fuel gas outlet 4b.

  On the other hand, the oxidant gas supplied to the oxidant gas inlet 5a is supplied to an electrode (not shown) through an oxidant gas flow path 7 formed continuously between the protrusions 3 on the other surface 1b of the separator plate 1. At the same time, unused oxidant gas is discharged to the oxidant gas outlet 5b.

JP-A-8-222237 (FIG. 1)

  However, in the separator plate 1, the protrusions 2 and 3 are formed so as to protrude to different surfaces 1 a and 1 b, and the fuel gas flow path 6 and the oxidant gas flow path 7 are formed by the independent protrusions 2 and 3. Has been. For this reason, the fuel gas and the oxidant gas do not flow uniformly in the surfaces 1a and 1b, and there is a region where the fuel gas and the oxidant gas are not sufficiently supplied in the fuel gas channel 6 and the oxidant gas channel 7. easy.

  Specifically, in the fuel gas flow path 6 and the oxidant gas flow path 7, in particular, a large amount of fuel gas and oxidant gas easily flow in the vicinity of the in-plane central portion of the separator plate 1, and the fuel gas and the oxidant gas flow. Distribution (flow velocity) varies within the plane of the separator plate 1. Accordingly, it has been pointed out that it is difficult to uniformly supply fuel gas and oxidant gas into the electrode surface, and uniform power generation cannot be performed over the entire power generation surface.

  On the other hand, in the separator plate 1, similarly, a cooling medium flow path may be formed in communication between the protrusions. At this time, if a portion where the cooling medium is difficult to flow is generated, there is a problem in that the electrode is not sufficiently cooled during power generation, and the temperature rises and resistance overvoltage increases due to a decrease in humidity.

  Further, the power generation distribution in the power generation plane varies, and the durability is lowered due to the temperature rise of the electrolyte membrane. If an attempt is made to flow a large amount of cooling medium in order to prevent this kind of performance degradation, the efficiency of the entire system is lowered and a problem of increased pressure loss is caused.

  The present invention solves this type of problem, and can smoothly and uniformly supply a fluid such as a reaction gas along the surface of the separator, and obtains good power generation performance with a small and simple configuration. An object of the present invention is to provide a fuel cell that can be used.

  In the fuel cell according to the present invention, the electrolyte / electrode structure provided with electrodes on both sides of the electrolyte and the metal separator are alternately laminated, and at least a reaction gas communication hole is formed through the lamination direction. . On one surface of the metal separator, a plurality of first protrusions projecting toward the electrode are provided, and one fluid flow path is formed along the one surface between the first protrusions, The other surface of the metal separator is provided with a plurality of second protrusions projecting on the opposite side to the first protrusion, and the other fluid flow is provided along the other surface between the second protrusions. A road is formed.

  And the 1st projection part of the in-plane center part of a metal separator is set to a size larger than the 1st projection part of the other part, and the 2nd projection part of the in-plane center part of the metal separator is other The dimension is set to be larger than that of the second projecting portion. Here, the first and second protrusions refer to, for example, convex portions including embossing or dimples.

  Moreover, it is preferable that a 1st and 2nd projection part is comprised by circular shape by planar view. Further, the reaction gas communication hole includes a reaction gas supply communication hole and a reaction gas discharge communication hole provided at opposite sides and point symmetrical positions of the metal separator, and the reaction gas supply communication hole includes the fuel gas supply communication hole and the oxidant. The reaction gas discharge communication hole has a fuel gas discharge communication hole and an oxidant gas discharge communication hole, and the fuel gas supply communication hole and the oxidant gas discharge communication hole are the same. The oxidant gas supply communication hole and the fuel gas discharge communication hole are preferably provided on the same side.

  Furthermore, a cooling medium communication hole is formed penetrating in the stacking direction, and the cooling medium communication hole is provided on the opposite side perpendicular to the side where the reaction gas supply communication hole and the reaction gas discharge communication hole of the metal separator are provided. It is preferable to provide a cooling medium supply communication hole and a cooling medium discharge communication hole.

  The fluid flow path preferably includes any one of a fuel gas flow path for supplying a fuel gas, an oxidant gas flow path for supplying an oxidant gas, or a cooling medium flow path for supplying a cooling medium. The reaction surface is preferably set to be approximately square.

  In the present invention, since the first and second protrusions of the in-plane center portion of the metal separator are set to be larger than the other portions, the fluid such as the reaction gas and the cooling medium flowing through the in-plane center portion , Resistance increases and the flow rate tends to decrease. Therefore, the flow rate of the fluid is made uniform over the plane of the metal separator, and the fluid distribution property is effectively improved. As a result, uniform power generation is performed on the entire power generation surface, and good and efficient power generation performance can be obtained with a small and simple configuration.

  FIG. 1 is an exploded perspective view of a main part of a fuel cell 10 according to an embodiment of the present invention, and FIG. 2 is a partial cross-sectional explanatory view of a power generation cell 12 constituting the fuel cell 10. As shown in FIG. 1, the fuel cell 10 has a plurality of power generation cells 12 stacked in the arrow A direction.

  The power generation cell 12 includes an electrolyte membrane / electrode structure (electrolyte / electrode structure) 14 and first and second metal separators 16 and 18 that sandwich the electrolyte membrane / electrode structure 14. The first and second metal separators 16 and 18 are formed into a desired shape by press molding using a thin metal plate such as a steel plate, a stainless steel plate, an aluminum plate, or a plated steel plate.

  One end edge of the power generation cell 12 in the direction of arrow B (the horizontal direction in FIG. 1) communicates with each other in the direction of arrow A, which is the stacking direction, and oxidant for supplying an oxidant gas, for example, an oxygen-containing gas. An agent gas supply communication hole (reaction gas communication hole) 20a and a fuel gas discharge communication hole (reaction gas communication hole) 22b for discharging a fuel gas, for example, a hydrogen-containing gas, are arranged in the arrow C direction (vertical direction). Arranged and provided.

  The other end edge of the power generation cell 12 in the direction of arrow B communicates with each other in the direction of arrow A, and a fuel gas supply communication hole (reaction gas communication hole) 22a for supplying fuel gas and an oxidant gas are discharged. Oxidant gas discharge communication holes (reactive gas communication holes) 20b are arranged in the arrow C direction. The oxidant gas supply communication hole 20a and the oxidant gas discharge communication hole 20b are provided at opposite sides and substantially diagonal positions (point symmetry positions), while the fuel gas supply communication hole 22a and the fuel gas discharge communication hole 22b are provided. Are provided at opposite positions and at substantially diagonal positions (point symmetry positions).

  One end edge (lower part) of the power generation cell 12 in the direction of arrow C is provided with a cooling medium supply communication hole 24a that communicates with each other in the direction of arrow A and supplies a cooling medium. The other end edge (upper part) in the C direction is provided with a cooling medium discharge communication hole 24b for discharging the cooling medium. Similarly, the cooling medium supply communication hole 24a and the cooling medium discharge communication hole 24b are provided at opposite positions and substantially at diagonal positions (point symmetry positions).

  The electrolyte membrane / electrode structure 14 includes, for example, a solid polymer electrolyte membrane (electrolyte) 26 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode side electrode 28 and an anode sandwiching the solid polymer electrolyte membrane 26 Side electrode 30. As for the cathode side electrode 28 and the anode side electrode 30, each reaction surface (electric power generation surface) is set in the substantially square shape.

  As shown in FIG. 2, the cathode side electrode 28 and the anode side electrode 30 include gas diffusion layers 32a and 32b made of carbon paper or the like, and porous carbon particles carrying platinum alloy on the surface thereof. Electrode catalyst layers 34a and 34b uniformly applied to the surface of 32b. The electrode catalyst layers 34 a and 34 b are bonded to both surfaces of the solid polymer electrolyte membrane 26.

  As shown in FIGS. 1 and 3, an oxidant gas flow path (fluid flow path) 36 is provided on a surface 16 a of the first metal separator 16 facing the electrolyte membrane / electrode structure 14, and the oxidant gas. The flow path 36 communicates with the oxidant gas supply communication hole 20a and the oxidant gas discharge communication hole 20b.

  As shown in FIGS. 1 and 4, the fuel gas flow connecting the fuel gas supply communication hole 22 a and the fuel gas discharge communication hole 22 b to the surface 18 a of the second metal separator 18 facing the electrolyte membrane / electrode structure 14. A channel (fluid channel) 38 is formed. Between the surface 18b of the second metal separator 18 and the surface 16b of the first metal separator 16, a cooling medium flow path (fluid flow path) 40 that connects the cooling medium supply communication hole 24a and the cooling medium discharge communication hole 24b. Is formed.

  As shown in FIG. 3, the surface 16a of the first metal separator 16 is provided with a plurality of protrusions protruding toward the cathode side electrode 28, for example, a circular embossed portion 42 in plan view. A plurality of embossed portions 42 a having a larger diameter (larger dimensions) than the embossed portion 42 are provided in the central portion of the surface 16 a of the first metal separator 16. The interval between the embossed portions 42 and the interval between the embossed portions 42a are set to the same distance a1. The oxidant gas flow path 36 is formed between the embossed portions 42 and 42a alone.

  The surface 16b of the first metal separator 16 is provided with a plurality of protrusions protruding toward the second metal separator 18, for example, a circular embossed portion 44 in plan view. The embossed portion 44 is set to have a smaller diameter than the embossed portion 42. A plurality of embossed portions 44 a having a larger diameter (larger dimensions) than the embossed portion 44 are provided in the central portion of the surface 16 b of the first metal separator 16. The interval between the embossed portions 44 and the interval between the embossed portions 44a are set to the same distance a2.

  The first seal member 46 is integrated with the surfaces 16a and 16b of the first metal separator 16 by baking or injection molding around the outer peripheral end of the first metal separator 16. The first seal member 46 uses, for example, a seal material such as EPDM, NBR, fluorine rubber, silicon rubber, fluorosilicon rubber, butyl rubber, natural rubber, styrene rubber, chloroplane, or acrylic rubber, a cushion material, or a packing material. To do.

  As shown in FIG. 4, the surface 18 a of the second metal separator 18 is provided with a plurality of protrusions protruding toward the anode-side electrode 30, for example, a circular embossed portion 48 in plan view. A plurality of embossed portions 48 a having a larger diameter (larger dimensions) than the embossed portion 48 are provided in the central portion of the surface 18 a of the second metal separator 18. The distance between the embossed parts 48 and the distance between the embossed parts 48a are set to the same distance a1. A fuel gas flow path 38 is formed between the embossed portions 48 and 48a alone.

  The surface 18b of the second metal separator 18 is provided with a plurality of protrusions protruding toward the first metal separator 16, for example, a circular embossed portion 50 in plan view. The embossed portion 50 is set to have a smaller diameter than the embossed portion 48. A plurality of embossed portions 50 a having a larger diameter (larger dimensions) than the embossed portion 50 are provided in the central portion of the surface 18 b of the second metal separator 18. The distance between the embossed parts 50 and the distance between the embossed parts 50a are set to the same distance a2.

  The second seal member 52 is integrated with the surfaces 18a and 18b of the second metal separator 18 by baking or injection molding around the outer peripheral end of the second metal separator 18. The second seal member 52 is configured similarly to the first seal member 46.

  The operation of the fuel cell 10 configured as described above will be described below.

  As shown in FIG. 1, a fuel gas such as a hydrogen-containing gas, an oxidant gas such as air that is an oxygen-containing gas, and a cooling medium such as pure water, ethylene glycol, or oil are supplied into the fuel cell 10. Is done. For this reason, in the fuel cell 10, the fuel gas, the oxidant gas, and the cooling medium are supplied to the plurality of sets of power generation cells 12 superimposed in the direction of arrow A.

  As shown in FIGS. 1 and 4, the fuel gas supplied to the fuel gas supply communication hole 22a communicating in the direction of arrow A is introduced into the fuel gas flow path 38 of the second metal separator 18, and the electrolyte membrane / It moves along the anode side electrode 30 constituting the electrode structure 14. On the other hand, as shown in FIGS. 1 and 3, the oxidant gas is introduced into the oxidant gas flow path 36 provided in the first metal separator 16, and constitutes the electrolyte membrane / electrode structure 14. Move along 28.

  Accordingly, in each electrolyte membrane / electrode structure 14, the fuel gas supplied to the anode side electrode 30 and the oxidant gas supplied to the cathode side electrode 28 are electrochemically reacted in the electrode catalyst layers 34 a and 34 b. It is consumed and power is generated (see FIG. 2).

  Next, the consumed fuel gas supplied to the anode side electrode 30 is discharged to the fuel gas discharge communication hole 22b (see FIG. 4). Similarly, the oxidant gas consumed by being supplied to the cathode side electrode 28 is discharged to the oxidant gas discharge communication hole 20b (see FIG. 3).

  Further, the cooling medium supplied to the cooling medium supply communication hole 24 a is introduced into the cooling medium flow path 40 between the first and second metal separators 16 and 18. The cooling medium cools the electrolyte membrane / electrode structure 14 while moving vertically upward, and is then discharged into the cooling medium discharge communication hole 24b (see FIG. 1).

  In this case, in the present embodiment, for example, as shown in FIG. 3, the oxidant gas flow path 36 provided on the surface 16 a of the first metal separator 16 is formed by a plurality of embossed portions 42. A plurality of embossed portions 42a having a diameter larger than that of the embossed portion 42 are provided in the central portion of the surface 16a. Therefore, the oxidant gas supplied from the oxidant gas supply communication hole 20a to the oxidant gas flow path 36 flows uniformly over the entire reaction surface (power generation surface) of the cathode side electrode 28, and then the oxidant gas discharge communication. It is discharged into the hole 20b.

  Specifically, when the oxidant gas flow path 36 is formed using only the plurality of embossed portions 42 having the same diameter on the surface 16a of the first metal separator 16, that is, when the large-diameter embossed portion 42a is not provided, As shown in FIG. 5, the flow rate of the oxidant gas greatly fluctuated in each cross section α-α. This cross section α-α indicates cross-sectional positions along α1-α2, α3-α4, and α5-α6 shown in FIG.

  As a result, when the oxidant gas flow path 36 is formed using only the embossed portions 42 having the same dimensions, a large amount of oxidant gas flows near the central portion of the surface 16a. ) Variation.

  On the other hand, when the embossed portion 42a having a larger diameter than the other embossed portions 42 is provided in the central portion of the surface 16a, that is, in the case of the present embodiment, as shown in FIG. The flow rate of the oxidant gas became substantially uniform. This is because the flow rate of the oxidant gas is reduced by the large-diameter embossed portion 42a provided in the center portion of the surface 16a, and the flow rate of the oxidant gas is made uniform over the surface 16a.

  For this reason, in the present embodiment, the oxidant gas distribution property is effectively improved over the entire power generation surface of the cathode side electrode 28, uniform power generation is performed, and a small and simple configuration is favorable and efficient. The effect of being able to obtain power generation performance was obtained.

  Similarly, when the fuel gas passage 38 is formed using only the embossed portion 48 having the same diameter on the surface 18a, that is, when the large-diameter embossed portion 48a is not provided, as shown in FIG. Variations in fuel gas flow velocity occurred along -α.

  On the other hand, as shown in FIG. 4, when the embossed portion 48a having a larger diameter than the other embossed portions 48 is provided at the center portion of the surface 18a of the second metal separator 18, that is, in the present embodiment, As shown in FIG. 8, the flow rate of the fuel gas along the cross section α-α was made uniform.

  Furthermore, when the cooling medium flow path 40 is formed only by the embossed portions 44 and 50 between the first and second metal separators 16 and 18, that is, when the large-diameter embossed portions 44a and 50a are not provided, FIG. In the cross section β-β along β1-β2, β3-β4, and β5-β6, the flow rate of the cooling medium changed greatly (see FIG. 9).

  On the other hand, in the present embodiment in which the large-diameter embossed portions 44a and 50a are provided, as shown in FIG. 10, the flow rate of the central portion is effectively suppressed, and a uniform cooling medium flow rate is obtained as a whole. . Thereby, uniform and favorable cooling is performed along the entire surface of the electrolyte membrane / electrode structure 14, and the effect that the power generation performance can be improved is obtained.

  Furthermore, as shown in FIG. 3, the distance between the embossed parts 42 and the distance between the embossed parts 42a are set to the same distance a1, thereby facilitating the production of the embossing mold and press formability. There is an advantage that you can.

  In the present embodiment, the embossed portions 42, 42a, 44, 44a, 48, 48a, 50, and 50a are formed in a circular shape in plan view. For this reason, it becomes possible to smoothly rectify and flow the oxidant gas, the cooling medium, and the fuel gas.

  Furthermore, the oxidant gas supply communication hole 20a and the oxidant gas discharge communication hole 20b are provided at opposite positions and at substantially diagonal positions (point symmetry positions). Therefore, the oxidant gas flow path 36 does not have a bent portion and is configured in a substantially straight line, so that the oxidant gas can flow smoothly.

  Similarly, the fuel gas supply communication hole 22a and the fuel gas discharge communication hole 22b are provided at opposite positions and substantially diagonal positions, and the cooling medium supply communication hole 24a and the cooling medium discharge communication hole 24b are opposite positions. And provided at substantially diagonal positions. As a result, the fuel gas and the cooling medium can flow smoothly and linearly without a bent portion.

  Furthermore, the cathode side electrode 28 and the anode side electrode 30 have their reaction surfaces (power generation surfaces) set to be substantially square. For this reason, the reaction surface can take the largest reaction area with respect to the outer peripheral length, and the power generation efficiency can be easily improved.

  In the present embodiment, the case where the first and second metal separators 16 and 18 are provided with the embossed portions 42, 42a, 44, 44a, 48, 48a, 50, and 50a that are embossed as protrusions has been described. However, the present invention is not limited to this. For example, a dimple portion (not shown) that has been dimple processed may be used.

  In the present embodiment, a configuration in which the cooling medium flow path 40 is provided between the first and second metal separators 16 and 18 is adopted, but the present invention is not limited to this, and the cooling medium flow path 40 is not limited to this. You may provide intermittently for every predetermined number of power generation cells 12. FIG.

It is a principal part disassembled perspective view of the fuel cell which concerns on embodiment of this invention. It is a partial cross section explanatory view of the power generation cell which constitutes the fuel cell. It is front explanatory drawing of the 1st metal separator which comprises the said fuel cell. It is front explanatory drawing of the 2nd metal separator which comprises the said fuel cell. It is flow velocity explanatory drawing of oxidant gas at the time of providing only the embossed part of the same dimension. It is explanatory drawing of the flow velocity of the oxidizing gas of this embodiment. It is explanatory drawing of the flow velocity of fuel gas when only the embossed part of the same dimension is provided. It is explanatory drawing of the flow velocity of the fuel gas of this embodiment. It is explanatory drawing of the flow velocity of a cooling medium when only the embossed part of the same dimension is provided. It is explanatory drawing of the flow velocity of the cooling medium of this embodiment. It is front explanatory drawing of the separator plate which concerns on patent document 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 12 ... Power generation cell 14 ... Electrolyte membrane electrode assembly 16, 18 ... Metal separator 20a ... Oxidant gas supply communication hole 20b ... Oxidant gas discharge communication hole 22a ... Fuel gas supply communication hole 22b ... Fuel gas discharge Communication hole 24a ... Cooling medium supply communication hole 24b ... Cooling medium discharge communication hole 26 ... Solid polymer electrolyte membrane 28 ... Cathode side electrode 30 ... Anode side electrode 36 ... Oxidant gas flow path 38 ... Fuel gas flow path 40 ... Cooling medium Flow path 42, 42a, 44, 44a, 48, 48a, 50, 50a ... Embossed part

Claims (6)

A fuel cell in which an electrolyte / electrode structure provided with electrodes on both sides of an electrolyte and a metal separator are alternately laminated, and at least a reaction gas communication hole is formed through the lamination direction,
A plurality of first protrusions projecting toward the electrode are provided on one surface of the metal separator, and one fluid flow path is formed along the one surface between the first protrusions. With
The other surface of the metal separator is provided with a plurality of second protrusions projecting on the opposite side of the first protrusion, and the other fluid flow along the other surface between the second protrusions. A road is formed,
The first protrusion of the in-plane central portion of the metal separator is set to a size larger than the first protrusion of the other portion, and the second protrusion of the in-plane central portion of the metal separator is The fuel cell is characterized in that it is set to a size larger than that of the second protrusion of the other part.   2. The fuel cell according to claim 1, wherein the first and second protrusions are formed in a circular shape in plan view. 3. The fuel cell according to claim 1, wherein the reaction gas communication hole includes a reaction gas supply communication hole and a reaction gas discharge communication hole provided on opposite sides of the metal separator in a point-symmetric position,
The reactive gas supply communication hole has a fuel gas supply communication hole and an oxidant gas supply communication hole,
The reaction gas discharge communication hole has a fuel gas discharge communication hole and an oxidant gas discharge communication hole,
While the fuel gas supply communication hole and the oxidant gas discharge communication hole are provided on the same side,
The fuel cell according to claim 1, wherein the oxidant gas supply communication hole and the fuel gas discharge communication hole are provided on the same side. The fuel cell according to any one of claims 1 to 3, wherein a cooling medium communication hole is formed through the stacking direction,
The cooling medium communication hole includes a cooling medium supply communication hole and a cooling medium discharge communication hole provided on opposite sides of the metal separator that are orthogonal to the side where the reaction gas supply communication hole and the reaction gas discharge communication hole are provided. A fuel cell.   5. The fuel cell according to claim 1, wherein the fluid flow path supplies a fuel gas flow path for supplying a fuel gas, an oxidant gas flow path for supplying an oxidant gas, or a cooling medium. A fuel cell comprising any one of cooling medium flow paths. 6. The fuel cell according to claim 1, wherein a reaction surface of the electrode is set to be substantially square.

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