Fuel Cells

Abstract

To provide a fuel cell which has high gas sealing performance between unit cells, and which also has a coolant passage with a large cross-sectional area.SOLUTION: A fuel cell comprises a plurality of unit cells, a cooling plate, and a gasket. The cooling plate is disposed between two adjacent ones of the plurality of unit cells. The cooling plate is a corrugated plate having a plurality of recessed grooves which function as a coolant passage. The gasket has a first protruding part with a height greater than the thickness of the cooling plate, and it seals a manifold of the two adjacent unit cells. At least on part of a lateral portion of the first protruding part, the gasket has a second protruding part having a protrusion in the same direction as that of the first protruding part.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to fuel cells. [Background technology]

[0002] A fuel cell (FC) is a power generation device that is composed of one unit cell (hereinafter sometimes referred to as a cell) or a fuel cell stack (hereinafter sometimes simply referred to as a stack) made up of multiple stacked unit cells, and produces electrical energy through an electrochemical reaction between a fuel gas such as hydrogen and an oxidant gas such as oxygen. Note that the fuel gas and oxidant gas actually supplied to a fuel cell are often a mixture with gases that do not contribute to oxidation or reduction. In particular, the oxidant gas is often air that contains oxygen. In the following, the fuel gas and the oxidant gas may be simply referred to as "reactant gas" or "gas" without any particular distinction. In addition, both a single cell and a fuel cell stack formed by stacking single cells may be referred to as a fuel cell.

[0003] Various fuel cell technologies have been proposed. For example, Patent Document 1 discloses a cooling plate (corrugated fin) formed of a corrugated plate having grooves that function as air-cooling gas flow paths between two adjacent cells among a plurality of cells.

[0004] Patent Document 2 discloses an air-cooled metal separator plate that does not require cooling water.

[0005] Patent Document 3 discloses a fuel cell stack with improved cooling efficiency and a fuel cell system having the same. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2020-126782 A [Patent Document 2] Special Publication No. 2013-500567 [Patent Document 3] JP 2006-210351 A Summary of the Invention [Problem to be solved by the invention]

[0007] During the electrochemical reaction in a fuel cell, each cell generates heat. Some fuel cells have cooling plates between two adjacent cells and between the side of adjacent cells and the side plate, which cool each cell and prevent the temperature of the fuel cell from becoming excessively high. In addition to water-cooling, air-cooling is also being considered as a cooling method, but in that case, the heat capacity of the refrigerant air is smaller than that of water, so the volume flow rate for cooling is several tens of times that of water, and the refrigerant flow path must be much deeper than in the case of water-cooling. Although the above Patent Document 1 does not mention gaskets or seals, it can be seen from FIG. 2 of Patent Document 1 that the ends of the corrugated fins forming the air-cooling gas flow paths reach the ends of the cells. In such a case, two types of gaskets are required to seal between the corrugated fins and the first cell and between the corrugated fins and the second cell at the cell ends, and the number of parts increases. It is also expected that this will increase the complexity of assembly. If the ends of the corrugated fins are not allowed to reach the cell ends, only one type of gasket will be required, but the corrugated fins need to have a large folding pitch to increase the cross-sectional area of ​​the air-cooling gas flow paths. If the height of the gasket is increased according to the pitch, the gasket will be more likely to deform, such as becoming more wobbly when a load is applied, and may be twisted or bent, resulting in a decrease in sealing performance.

[0008] The present disclosure has been made in consideration of the above-mentioned circumstances, and has as its main object to provide a fuel cell that has high gas sealing properties between unit cells and a large cross-sectional area of ​​a coolant flow path. [Means for solving the problem]

[0009] The fuel cell of the present disclosure is a fuel cell, comprising: Multiple single cells, Cooling plate, and Equipped with a gasket, the cooling plate is disposed between two adjacent unit cells among the plurality of unit cells, The cooling plate is a corrugated plate having a plurality of grooves that function as refrigerant flow paths, the gasket has a first protrusion having a height greater than a thickness of the cooling plate, and seals manifolds of two adjacent unit cells; The gasket is characterized in that it includes a second protrusion having a protrusion in the same direction as the first protrusion, on at least a part of a side of the first protrusion.

[0010] In the fuel cell of the present disclosure, the second protrusion may have a height equal to or less than a height of the first protrusion.

[0011] In the fuel cell of the present disclosure, cooling water or air may be flowed through the coolant flow passage. Effect of the Invention

[0012] The fuel cell of the present disclosure has high gas sealing properties between the unit cells and a large cross-sectional area of ​​the coolant flow path. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is an exploded perspective view showing an example of a portion of a fuel cell according to the present disclosure. [Diagram 2] FIG. 2 is a plan view showing an example of a fuel cell according to the present disclosure. [Diagram 3] FIG. 3 is an E-E cross-sectional view of the fuel cell shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The fuel cell of the present disclosure is a fuel cell, comprising: Multiple single cells, Cooling plate, and Equipped with a gasket, the cooling plate is disposed between two adjacent unit cells among the plurality of unit cells, The cooling plate is a corrugated plate having a plurality of grooves that function as refrigerant flow paths, the gasket has a first protrusion having a height greater than a thickness of the cooling plate, and seals manifolds of two adjacent unit cells; The gasket is characterized in that it includes a second protrusion having a protrusion in the same direction as the first protrusion, on at least a part of a side of the first protrusion.

[0015] Compared to water cooling, air cooling requires several dozen times the volumetric flow rate for cooling, so the coolant flow path must be significantly deeper. Also, when the cooling components come into contact with the reaction system, corrosion resistance is required, so in the past, expensive and heavy SUS or Ti with surface treatment was used, or carbon separators with deep grooves machined were used. According to the present disclosure, the bipolar plate portion of two adjacent single cells is made up of three sheets, the separator of one single cell, the cooling plate, and the separator of the other single cell, eliminating the need for deep groove press molding of the separator. In particular, even in cases such as air-cooled systems where a large cooling space needs to be provided between the cells and the gasket is prone to deformation, the reliability of the seal between the cells is improved and integral molding is possible, which reduces the number of parts and the complexity of assembly. In addition, the improved reliability of the seal reduces the requirement for corrosion resistance of the cooling plate, so that materials such as aluminum, which is easy to bend and low cost, can be used for the cooling plate.

[0016] The fuel cell includes a plurality of unit cells, a cooling plate disposed between two adjacent unit cells, and a gasket.

[0017] The fuel cell is a fuel cell stack, which is a laminate of a plurality of unit cells. The number of stacked unit cells is not particularly limited, and may be, for example, 2 to several hundreds, 2 to 600, or 2 to 200. The fuel cell stack may include end plates, current collector plates, pressure plates, etc., at both ends in the stacking direction of the unit cells.

[0018] The single fuel cell may include a membrane electrode gas diffusion layer assembly (MEGA). The single fuel cell may include a first separator and a second separator sandwiching the membrane electrode gas diffusion layer assembly.

[0019] The membrane electrode gas diffusion layer assembly comprises, in this order, a first gas diffusion layer, a first catalyst layer, an electrolyte membrane, a second catalyst layer, and a second gas diffusion layer. Specifically, the membrane electrode gas diffusion layer assembly includes an anode gas diffusion layer, an anode catalyst layer, an electrolyte membrane, a cathode catalyst layer, and a cathode gas diffusion layer, in this order.

[0020] One of the first catalyst layer and the second catalyst layer is a cathode catalyst layer, and the other is an anode catalyst layer. The cathode (oxidant electrode) includes a cathode catalyst layer and a cathode-side gas diffusion layer. The anode (fuel electrode) includes an anode catalyst layer and an anode-side gas diffusion layer. The first catalyst layer and the second catalyst layer are collectively referred to as the catalyst layer, and the cathode catalyst layer and the anode catalyst layer are collectively referred to as the catalyst layer.

[0021] One of the first gas diffusion layer and the second gas diffusion layer is a cathode side gas diffusion layer, and the other is an anode side gas diffusion layer. The first gas diffusion layer is a cathode-side gas diffusion layer when the first catalyst layer is a cathode catalyst layer, and is an anode-side gas diffusion layer when the first catalyst layer is an anode catalyst layer. The second gas diffusion layer is a cathode-side gas diffusion layer when the second catalyst layer is a cathode catalyst layer, and is an anode-side gas diffusion layer when the second catalyst layer is an anode catalyst layer. The first gas diffusion layer and the second gas diffusion layer are collectively referred to as a gas diffusion layer or a diffusion layer. The cathode side gas diffusion layer and the anode side gas diffusion layer are collectively referred to as a gas diffusion layer or a diffusion layer. The gas diffusion layer may be a gas-permeable conductive member or the like. Examples of the conductive member include porous carbon materials such as carbon cloth and carbon paper, and porous metal materials such as metal mesh and foamed metal.

[0022] The fuel cell may have a microporous layer (MPL) between the catalyst layer and the gas diffusion layer, which may include a mixture of a water-repellent resin such as PTFE and a conductive material such as carbon black.

[0023] The electrolyte membrane may be a solid polymer electrolyte membrane. Examples of the solid polymer electrolyte membrane include a fluorine-based electrolyte membrane such as a thin film of perfluorosulfonic acid containing water, and a hydrocarbon-based electrolyte membrane. The electrolyte membrane may be, for example, a Nafion membrane (manufactured by DuPont).

[0024] One of the first separator and the second separator is a cathode side separator, and the other is an anode side separator. The first separator is a cathode-side separator when the first catalyst layer is a cathode catalyst layer, and is an anode-side separator when the first catalyst layer is an anode catalyst layer. The second separator is a cathode-side separator when the second catalyst layer is a cathode catalyst layer, and is an anode-side separator when the second catalyst layer is an anode catalyst layer. The first separator and the second separator are collectively referred to as the separator, and the anode side separator and the cathode side separator are collectively referred to as the separator. The membrane electrode gas diffusion layer assembly is sandwiched between a first separator and a second separator. The separator may have supply holes and discharge holes for passing fluids such as reaction gases and coolants in the stacking direction of the single cells. In the case of a gas, cooling air or the like can be used as the coolant. In the case of a liquid, cooling water such as a mixed solution of ethylene glycol and water can be used to prevent freezing at low temperatures. Examples of the supply hole include a fuel gas supply hole, an oxidant gas supply hole, and a coolant supply hole. Examples of the exhaust hole include a fuel gas exhaust hole, an oxidant gas exhaust hole, and a coolant exhaust hole. The separator may have one or more fuel gas supply holes, may have one or more oxidant gas supply holes, may have one or more coolant supply holes as required, may have one or more fuel gas discharge holes, may have one or more oxidant gas discharge holes, and may have one or more coolant discharge holes as required. The separator may have a reactant gas flow path on the surface in contact with the gas diffusion layer, and may have a coolant flow path on the surface opposite to the surface in contact with the gas diffusion layer to maintain a constant temperature of the fuel cell. When the separator is an anode-side separator, it may have one or more fuel gas supply holes, or may have one or more oxidant gas supply holes, or may have one or more coolant supply holes as necessary, or may have one or more fuel gas discharge holes, or may have one or more oxidant gas discharge holes, or may have one or more coolant discharge holes as necessary. The anode-side separator may have a fuel gas flow path on the surface in contact with the anode-side gas diffusion layer, which allows fuel gas to flow from the fuel gas supply hole to the fuel gas discharge hole, and may have a coolant flow path on the surface opposite to the surface in contact with the anode-side gas diffusion layer, which allows coolant to flow from the coolant supply hole to the coolant discharge hole. When the separator is a cathode-side separator, it may have one or more fuel gas supply holes, one or more oxidant gas supply holes, and optionally one or more coolant supply holes, one or more fuel gas discharge holes, one or more oxidant gas discharge holes, and optionally one or more coolant discharge holes. The cathode-side separator may have an oxidant gas flow path on the surface in contact with the cathode-side gas diffusion layer, which allows oxidant gas to flow from the oxidant gas supply holes to the oxidant gas discharge holes, and may have a refrigerant flow path on the surface opposite to the surface in contact with the cathode-side gas diffusion layer, which allows refrigerant to flow from the refrigerant supply holes to the refrigerant discharge holes, as necessary. The separator may be a gas-impermeable conductive member. Examples of the conductive member include resin materials such as thermosetting resin, thermoplastic resin, and resin fiber, press-molded carbon composite materials including carbon materials such as carbon powder and carbon fiber, dense carbon made by compressing carbon to make it gas-impermeable, and press-molded metal (e.g., titanium, iron, aluminum, and SUS) plates. The separator may also have a current collecting function.

[0025] The fuel cell may have manifolds, such as an inlet manifold to which the supply holes communicate, and an outlet manifold to which the exhaust holes communicate. The inlet manifolds include an anode inlet manifold, a cathode inlet manifold, and a coolant inlet manifold. The outlet manifold may include an anode outlet manifold, a cathode outlet manifold, and a coolant outlet manifold.

[0026] In this disclosure, the fuel gas and the oxidant gas are collectively referred to as reactant gases. The reactant gas supplied to the anode is the fuel gas, and the reactant gas supplied to the cathode is the oxidant gas. The fuel gas is a gas that mainly contains hydrogen, and may be hydrogen. The oxidant gas may be oxygen, air, dry air, etc.

[0027] The fuel cell may have a plastic frame. The resin frame is disposed around the outer periphery of the membrane electrode gas diffusion layer assembly, and may be disposed between the first separator and the second separator. The resin frame may also be a member for preventing cross-leakage or electrical short-circuiting between catalyst layers of a membrane electrode-gas diffusion layer assembly. The resin frame may have a framework, an opening, a supply hole, and a discharge hole. The framework is the main part of the resin frame that connects to the membrane electrode gas diffusion layer assembly. The opening is a holding area for the membrane electrode gas diffusion layer assembly, and is a through hole penetrating a part of the framework to accommodate the membrane electrode gas diffusion layer assembly. The opening may be located at a position in the resin frame where the framework is disposed around (outer periphery of) the membrane electrode gas diffusion layer assembly, and may be located in the center of the resin frame. The supply holes and exhaust holes allow reactant gases, coolants, etc. to flow in the stacking direction of the unit cells. The supply holes of the resin frame may be aligned and positioned so as to communicate with the supply holes of the separators. The exhaust holes of the resin frame may be aligned and positioned so as to communicate with the exhaust holes of the separators. The resin frame may include a frame-shaped core layer and two frame-shaped shell layers, that is, a first shell layer and a second shell layer, provided on both sides of the core layer. The first shell layer and the second shell layer may be provided in a frame shape on both sides of the core layer, similarly to the core layer.

[0028] The core layer may be a structural member having gas sealing and insulating properties, and may be formed of a material whose structure does not change even under the temperature conditions during thermocompression bonding in the manufacturing process of the fuel cell. Specifically, the material of the core layer may be, for example, polyethylene, polypropylene, PC (polycarbonate), PPS (polyphenylene sulfide), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PA (polyamide), PI (polyimide), PS (polystyrene), PPE (polyphenylene ether), PEEK (polyether ether ketone), cycloolefin, PES (polyethersulfone), PPSU (polyphenylsulfone), LCP (liquid crystal polymer), epoxy resin, or other resin. The material of the core layer may be a rubber material such as EPDM (ethylene propylene diene rubber), fluorine-based rubber, or silicon-based rubber. The thickness of the core layer may be 5 μm or more, or may be 30 μm or more, from the viewpoint of ensuring insulation, and may be 200 μm or less, or may be 150 μm or less, from the viewpoint of reducing the cell thickness.

[0029] The first and second shell layers may have properties such as high adhesiveness to other substances, softening under temperature conditions during thermocompression bonding, and lower viscosity and melting point than the core layer in order to bond the core layer to the anode-side separator and the cathode-side separator and ensure sealing properties. Specifically, the first and second shell layers may be thermoplastic resins such as polyester and modified olefin, or may be thermosetting resins such as modified epoxy resins. The first and second shell layers may be the same type of resin as the adhesive layer. The resin constituting the first shell layer and the resin constituting the second shell layer may be the same type of resin or different types of resin. By providing shell layers on both sides of the core layer, adhesion between the resin frame and the two separators by hot pressing becomes easy. The thickness of each of the first shell layer and the second shell layer may be 5 μm or more, or 20 μm or more, from the viewpoint of ensuring adhesion, and may be 100 μm or less, or 40 μm or less, from the viewpoint of reducing the cell thickness.

[0030] In the resin frame, the first shell layer and the second shell layer may be provided only in the portions that are bonded to the anode side separator and the cathode side separator, respectively. The first shell layer provided on one surface of the core layer may be bonded to the cathode side separator. The second shell layer provided on the other surface of the core layer may be bonded to the anode side separator. The resin frame may be sandwiched between a pair of separators.

[0031] The gasket has a first protrusion with a height greater than the thickness of the cooling plate and seals the manifolds of the two adjacent unit cells, thereby making it possible to achieve a structure in which the cooling plate is not exposed to the manifold and is not in contact with reactant gases such as oxidant gas and fuel gas. That is, the gasket is disposed between two adjacent unit cells, and seals the periphery of the manifold of the two adjacent unit cells so that the cooling plate is isolated from the manifold and the reactant gas flowing through the manifold does not leak into the area where the cooling plate is disposed. This allows the manifold to circulate the reactant gas only in the stacking direction in the area between the two adjacent unit cells, and prevents the reactant gas from leaking in the planar direction. When there are multiple manifolds, a gasket may be placed in each manifold to seal each manifold. Alternatively, a plate-shaped gasket having a structure capable of sealing each manifold may be placed. Of the manifolds, the refrigerant inlet manifold and the refrigerant outlet manifold do not need to be placed with gaskets, and may be connected to the refrigerant flow paths of the cooling plate and the separator. The gasket is provided with a second protrusion (side lip) having a protrusion in the same direction as the first protrusion, on at least a part of the side of the first protrusion. The second protrusion may be provided on at least a part of the side of the first protrusion, and may be provided on the entire circumference of the side, or may be provided in an area that occupies 50% of the circumference of the gasket. The second protrusion may be provided in an area that occupies 50% of the circumference of the gasket on the side of the first protrusion and on the opposite side to the side where the MEGA is arranged in the surface direction, that is, in an area on the outer side of the unit cell. This makes it difficult for the separator to twist in the inner area in the surface direction of the unit cell, thereby reducing manufacturing costs. By providing side lips, the side lips are compressed, so that the adhesive line of the cell seal under the foot of the gasket is constantly compressed and less likely to peel off. The side lips also suppress torsional damage of the separator. The fact that separator twisting can be suppressed has been confirmed by the researchers through calculation results using the finite element method (FEM). The height of the second convex portion may be the same as, higher than, or lower than the height of the first convex portion, but may also be equal to or lower than the height of the first convex portion. The gasket may be made of ethylene propylene diene rubber (EPDM) rubber, silicone rubber, thermoplastic elastomer resin, or the like. The height of the gasket may be greater than 50% of the thickness of a unit cell-cooling plate assembly including one unit cell and one cooling plate. The thickness of the single cell referred to here means the thickness including the first separator, the resin frame that houses the MEGA in the opening, and the second separator.

[0032] The cooling plate is disposed between two adjacent unit cells among the plurality of unit cells. The cooling plate may be disposed in at least a part of the area in the planar direction between two adjacent unit cells, so long as the cooling plate is disposed between two adjacent unit cells. The cooling plate may be disposed between two adjacent single cells in the planar direction in at least a region facing the MEGA. The cooling plate may be disposed in an area other than the area where the gasket is disposed between two unit cells adjacent to each other in the planar direction. The cooling plate may be disposed in a region other than the region where the gasket is disposed between two adjacent unit cells in the planar direction, and may be disposed in a region excluding the outer peripheral edge portion in the planar direction between the two adjacent unit cells. In other words, the cooling plate may be disposed between the two adjacent unit cells such that the end of the cooling plate in the planar direction does not reach the end of the unit cell in the planar direction. The cooling plate may be disposed in a region facing the MEGA other than the region where the gasket is disposed between two unit cells adjacent in the planar direction. The cooling plate is a corrugated plate having a plurality of grooves that function as coolant flow paths. Cooling water or cooling air may flow through the coolant flow passage, or cooling air may flow. The cooling plate can increase the volume of the coolant flow passage. Therefore, when the coolant is air, a sufficient volume can be secured. Also, when the coolant is liquid, the capacity of the cooling pump can be reduced and pressure loss can be reduced. The cooling plate may be a metal plate such as aluminum folded into a corrugated shape, etc. The surface of the cooling plate may be electrically conductive, such as with silver, nickel, or carbon. The grooves in the cooling plate may be formed by bending. The depth of the groove may be, for example, 1.0 to 2.0 mm. The folding process may be performed to form recesses and protrusions at a pitch of, for example, a groove depth of 1.0 to 2.0 mm and a width of 1.0 to 2.0 mm.

[0033] FIG. 1 is an exploded perspective view showing an example of a portion of a fuel cell according to the present disclosure. The fuel cell includes an assembly 100 having a single cell 90 , a cooling plate 50 and a gasket 60 . The unit cell 90 has a first separator 20, a resin frame 40 that houses the MEGA in an opening, and a second separator 30, in this order. The cooling plate 50 is disposed in an area opposite to the MEGA, other than the area on the surface of the second separator 30 of the unit cell 90 where the gaskets 60 are disposed. Each gasket 60 is disposed around each manifold 80 on the surface of the second separator 30 facing the cooling plate 50 . The first separator 20, the resin frame 40, and the second separator 30 are provided with an oxidant gas supply hole, an oxidant gas discharge hole, a fuel gas supply hole, and a fuel gas discharge hole, which are manifolds 80 through which the oxidant gas, which is reaction air, or the fuel gas, which is hydrogen, can flow, as shown by the arrows. The cooling plate 50 is provided with a plurality of recessed grooves that serve as coolant flow paths through which cooling air, which is a coolant, can flow as shown by the arrows.

[0034] FIG. 2 is a plan view showing an example of a fuel cell according to the present disclosure. The fuel cell 200 is provided with a gasket 60 and a manifold 80 . FIG. 3 is an E-E cross-sectional view of the fuel cell shown in FIG. The fuel cell 200 is constructed by stacking a plurality of unit cells 90 . The fuel cell 200 includes a plurality of unit cells 90, and a cooling plate 50 and a gasket 60 between two adjacent unit cells 90. The fuel cell includes an assembly 100 having a single cell 90 , a cooling plate 50 and a gasket 60 . The unit cell 90 has a first separator 20, a resin frame 40 that houses the MEGA 10 in an opening portion, and a second separator 30, in this order. The cooling plate 50 is arranged in an area facing the MEGA other than the area where the gasket 60 is arranged between the second separator 30 of one of the two adjacent single cells 90 and the first separator 20 of the other single cell 90. The gasket 60 is disposed around the manifold 80 in a region between the second separator 30 of one unit cell 90 and the first separator 20 of the other unit cell 90 of two adjacent unit cells 90 . The gasket 60 has a first protrusion 61, and a second protrusion 70 in at least a part of the periphery of the first protrusion 61 on the opposite side to the MEGA 10 in the planar direction.

[0035] An example of a method for manufacturing a fuel cell according to the present disclosure is as follows. A press-molded carbon resin composite material (with a flow channel depth of, for example, 0.3 mm) is prepared as the first separator and the second separator. A gasket (EPDM rubber or silicone rubber) is molded around the manifold on one side of the first separator. The gasket may also be attached to the second separator. Also, instead of molding the gasket onto the separator, the gasket may be molded onto a mold and then transferred to the separator. A resin frame is prepared by punching out a sheet (for example, 0.20 μm thick) of PEN coated with an adhesive thermoplastic resin into a frame shape. A membrane electrode gas diffusion layer assembly having a first gas diffusion layer, a first catalyst layer, an electrolyte membrane, a second catalyst layer, and a second gas diffusion layer in this order is prepared. A frame-shaped resin frame and the membrane electrode gas diffusion layer assembly are joined by an adhesive at the end of the rectangular membrane electrode gas diffusion layer assembly to obtain a resin frame-MEGA assembly. The resin frame-MEGA assembly is sandwiched between the first separator and the second separator so that the surface of the first separator opposite to the surface on which the gasket is formed is in contact with the resin frame-MEGA assembly. The first separator and the resin frame are then welded by heat pressing, and the second separator and the resin frame are welded to obtain a second separator-resin frame-MEGA-first separator assembly. This results in a single cell having the second separator, the resin frame that houses the MEGA in its opening, and the first separator, in that order. A cooling plate is prepared by bending an aluminum sheet (thickness 0.10 mm) plated with Ag (50 nm) to form recesses with a depth of 1.5 mm and a pitch of 1.5 mm. A cooling plate is placed on the surface of the first separator of the single cell opposite the surface that contacts the MEGA. Adhesive is placed on the four corners of the cooling plate on the first separator side to bond the first separator and the cooling plate. This results in an assembly with the cooling plate and gasket on the surface of the first separator of the single cell. Then, another unit cell is prepared, and adhesive is placed on the four corners of the cooling plate of the assembly on the second separator side of the other unit cell, and the second separator of the other unit cell is bonded to the cooling plate. This results in a fuel cell in which a cooling plate and a gasket are placed between two adjacent unit cells. In a similar manner, a plurality of unit cells may be stacked so that a cooling plate and a gasket are placed between two adjacent unit cells to obtain a stack. If necessary, a current collector plate and a pressure plate may be placed in this order on both ends of the stack to form a fuel cell (fuel cell stack). [Explanation of symbols]

[0036] 10 MEGA 20 First separator 30 Second separator 40 Resin Frame 50 Cooling plate 60 Gasket 61 First protrusion 70 Second protrusion 80 Manifold 90 Single Cell 100 aggregates 200 Fuel Cell

Claims

1. An air-cooled fuel cell, Multiple single cells, Cooling plate, and Equipped with a gasket, the cooling plate is disposed between two adjacent unit cells among the plurality of unit cells, the cooling plate is a corrugated plate having a plurality of grooves that function as refrigerant flow paths, the gasket has a first protrusion having a height greater than a thickness of the cooling plate and seals manifolds of two adjacent unit cells, the unit cell includes a membrane electrode gas diffusion layer assembly, a first separator and a second separator sandwiching the membrane electrode gas diffusion layer assembly, and a resin frame disposed on an outer periphery of the membrane electrode gas diffusion layer assembly and between the first separator and the second separator, the first protrusion is disposed so as to surround the periphery of the manifold, the gasket includes a second protrusion having a protrusion in the same direction as the first protrusion, in a region of the outer periphery of the first protrusion, occupying 50% of the circumferential length of the outer periphery of the first protrusion, and in a region on the opposite side to the side on which the membrane electrode gas diffusion layer assembly is disposed in a planar direction based on the manifold, The second protrusion has the same height as the first protrusion, A fuel cell, wherein air flows through the coolant passage.

2. 2. The fuel cell according to claim 1, wherein the material of the cooling plate is aluminum.

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