JP2016012444A - Fuel cell and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to securely suppress peeling between a step electrolyte membrane electrode structure and a resin frame member and such with a simple structure and a step.SOLUTION: A framed step electrolyte membrane electrode structure 12 is constituted by bonding a step MEA 12a and a resin frame member 24. Between an inner periphery projection 24a of the resin frame member 24 and an outer peripheral edge of the step MEA 12a, a frame shaped adhesive sheet 26 is provided. An inner periphery of the adhesive sheet 26 has an overlapping portion 26a where a surface of an outer periphery of a second gas diffusion layer 22b overlaps in an electrode thickness direction.

Description

  The present invention relates to a fuel cell including a stepped electrolyte membrane / electrode structure with a frame in which a stepped electrolyte membrane / electrode structure and a resin frame member are joined, and a manufacturing method thereof.

  In general, a polymer electrolyte fuel cell employs a polymer electrolyte membrane made of a polymer ion exchange membrane. A fuel cell has an electrolyte membrane / electrode structure (MEA) in which an anode electrode and a cathode electrode each comprising a catalyst layer (electrode catalyst layer) and a gas diffusion layer (porous carbon) are disposed on both sides of a solid polymer electrolyte membrane. ). The electrolyte membrane / electrode structure is sandwiched between separators (bipolar plates). A predetermined number of fuel cells are stacked to constitute a fuel cell stack, and are used as, for example, an in-vehicle fuel cell stack.

  In the electrolyte membrane / electrode structure, one gas diffusion layer is set to a smaller surface area than the solid polymer electrolyte membrane, and the other gas diffusion layer is set to the same surface area as the solid polymer electrolyte membrane. A so-called step MEA may be configured. At that time, a step MEA with a frame incorporating a resin frame member is used to reduce the amount of use of a relatively expensive solid polymer electrolyte membrane and to protect the solid polymer electrolyte membrane that is thin and low in strength. Has been.

  For example, an electrolyte membrane-electrode assembly disclosed in Patent Document 1 is known. In this electrolyte membrane-electrode assembly, as shown in FIG. 8, an anode catalyst layer 2a and an anode gas diffusion layer 2b are disposed on one side of the membrane 1. On the other side of the membrane 1, a cathode catalyst layer 3a and a cathode gas diffusion layer 3b are disposed. Thus, the step MEA 4 is configured.

  The anode gas diffusion layer 2b is set to have a larger area than the cathode gas diffusion layer 3b, and the outer peripheral portion of the film 1 on the cathode gas diffusion layer 3b side and the gasket structure 5 are joined via an adhesive layer 6. Has been.

JP 2007-66766 A

  By the way, in the above-mentioned Patent Document 1, the outer peripheral edge (plane) of the film 1 on the cathode gas diffusion layer 3 b side and the plane of the inner peripheral thin portion 5 a of the gasket structure 5 are interposed via the frame-shaped adhesive layer 6. It is joined. For this reason, there exists a problem that the adhesive strength of level | step difference MEA4 and the gasket structure 5 falls easily, and the edge part peeling and damage of the level | step difference MEA4 are caused.

  The present invention solves this type of problem, and a fuel cell capable of reliably suppressing peeling of the step electrolyte membrane / electrode structure and the resin frame member with a simple configuration and process and its An object is to provide a manufacturing method.

  The fuel cell according to the present invention includes a stepped electrolyte membrane / electrode structure with a frame to which a stepped electrolyte membrane / electrode structure and a resin frame member are joined. In the step electrolyte membrane / electrode structure, a first electrode having a first catalyst layer and a first gas diffusion layer is disposed on one surface of the solid polymer electrolyte membrane, and the other electrode of the solid polymer electrolyte membrane is provided. A second electrode having a second catalyst layer and a second gas diffusion layer is disposed on the surface. The planar dimension of the first gas diffusion layer is set to be larger than the planar dimension of the second gas diffusion layer. The resin frame member has a frame shape that circulates around the outer periphery of the solid polymer electrolyte membrane, and is provided with an inner peripheral protrusion that is formed thinly through the step and protrudes toward the second gas diffusion layer. Yes.

  A frame-shaped adhesive sheet is provided between the inner peripheral protrusion of the resin frame member and the outer peripheral edge of the step electrolyte membrane / electrode structure, and the inner peripheral edge of the adhesive sheet is a second gas. It has the overlap part which overlaps with the surface of the outer peripheral edge part of a diffused layer in an electrode thickness direction.

  In the fuel cell, it is preferable that the overlapping portion of the adhesive sheet is impregnated in the outer peripheral edge of the second gas diffusion layer.

  Furthermore, the manufacturing method of the fuel cell according to the present invention includes a step of separately manufacturing the stepped electrolyte membrane / electrode structure and the resin frame member, the frame shape, and the opening size of the inner periphery of the second gas diffusion layer. And a step of producing an adhesive sheet smaller than the outer dimension. Furthermore, this manufacturing method has the process of adhere | attaching the inner peripheral protrusion part of a resin frame member, and the outer periphery part of a level | step difference electrolyte membrane and electrode structure with an adhesive sheet.

  Furthermore, this manufacturing method preferably includes a step of impregnating the inner peripheral edge of the adhesive sheet into the outer peripheral edge of the second gas diffusion layer.

  According to the present invention, the frame-shaped adhesive sheet is interposed between the inner peripheral protrusion of the resin frame member and the outer peripheral edge of the step electrolyte membrane / electrode structure, and the inner peripheral edge is the second gas. The surface of the outer peripheral edge of the diffusion layer overlaps with the electrode thickness direction. For this reason, the resin frame member and the step electrolyte membrane / electrode structure are firmly and reliably bonded via the adhesive sheet.

  Therefore, it is possible to reliably suppress peeling of the stepped electrolyte membrane / electrode structure and the resin frame member with a simple configuration and process.

1 is an exploded perspective view of a main part of a polymer electrolyte fuel cell according to a first embodiment of the present invention. FIG. 2 is a sectional view of the fuel cell taken along line II-II in FIG. 1. It is front explanatory drawing by the side of the anode electrode of the level | step difference electrolyte membrane and electrode structure with a frame which comprises the said fuel cell. It is explanatory drawing of the method of manufacturing the said level | step difference electrolyte membrane and electrode structure with a frame. It is explanatory drawing of the method of manufacturing the said level | step difference electrolyte membrane and electrode structure with a frame. It is explanatory drawing of the method of manufacturing the said level | step difference electrolyte membrane and electrode structure with a frame. It is principal part cross-sectional explanatory drawing of the polymer electrolyte fuel cell which concerns on the 2nd Embodiment of this invention. 6 is an explanatory diagram of an electrolyte membrane-electrode assembly disclosed in Patent Document 1. FIG.

  As shown in FIG.1 and FIG.2, the polymer electrolyte fuel cell 10 which concerns on the 1st Embodiment of this invention is laminated | stacked in the arrow A direction (for example, horizontal direction), for example, for vehicle-mounted. A fuel cell stack is configured.

  The fuel cell 10 sandwiches a stepped electrolyte membrane / electrode structure 12 with a frame between a first separator 14 and a second separator 16. The first separator 14 and the second separator 16 are made of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plating-treated steel plate, a metal plate whose surface is subjected to anticorrosion treatment, a carbon member, or the like.

  As shown in FIG. 2, the stepped electrolyte membrane / electrode structure 12 with a frame includes a step MEA (stepped electrolyte membrane / electrode structure) 12a. The step MEA 12a includes, for example, a solid polymer electrolyte membrane (cation exchange membrane) 18 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode electrode (first electrode) 20 sandwiching the solid polymer electrolyte membrane 18. And an anode electrode (second electrode) 22. The solid polymer electrolyte membrane 18 uses an HC (hydrocarbon) electrolyte in addition to a fluorine electrolyte.

  The anode electrode 22 has a smaller planar dimension than the solid polymer electrolyte membrane 18 and the cathode electrode 20. The cathode electrode 20 may have a smaller planar dimension than the solid polymer electrolyte membrane 18 and the anode electrode 22. At that time, the anode electrode 22 becomes the first electrode, while the cathode electrode 20 becomes the second electrode.

  The cathode electrode 20 is disposed on one surface 18 a of the solid polymer electrolyte membrane 18, and the anode electrode 22 is disposed on the other surface 18 b of the solid polymer electrolyte membrane 18.

  The cathode electrode 20 includes a first electrode catalyst layer (first catalyst layer) 20a joined to the surface 18a of the solid polymer electrolyte membrane 18, and a first gas diffusion layer 20b laminated on the first electrode catalyst layer 20a. Have The first electrode catalyst layer 20 a and the first gas diffusion layer 20 b are set to have the same planar dimensions, that is, the same planar dimensions as the solid polymer electrolyte membrane 18.

  The anode electrode 22 includes a second electrode catalyst layer (second catalyst layer) 22a joined to the surface 18b of the solid polymer electrolyte membrane 18, and a second gas diffusion layer 22b laminated on the second electrode catalyst layer 22a. Have The second electrode catalyst layer 22a is set to have a larger planar dimension than the second gas diffusion layer 22b (or the same planar dimension as the second gas diffusion layer 22b). The first electrode catalyst layer 20a has a larger planar dimension than the second electrode catalyst layer 22a, but the first electrode catalyst layer 20a and the second electrode catalyst layer 22a are set to the same planar dimension. May be.

  The first electrode catalyst layer 20a and the second electrode catalyst layer 22a form catalyst particles in which platinum particles are supported on carbon black. For example, a polymer electrolyte is used as an ion conductive binder. The catalyst paste prepared by uniformly mixing the catalyst particles in the polymer electrolyte solution is configured by printing, coating or transferring on both surfaces 18a and 18b of the solid polymer electrolyte membrane 18.

  The first gas diffusion layer 20b and the second gas diffusion layer 22b are formed by applying an underlayer (intermediate layer) containing carbon black and PTFE (polytetrafluoroethylene) particles to carbon paper. The underlayer is set to have the same planar dimensions as the carbon paper. In addition, what is necessary is just to provide a base layer as needed. The planar dimension of the first gas diffusion layer 20b is set to be larger than the planar dimension of the second gas diffusion layer 22b.

  As shown in FIGS. 1 and 2, the stepped electrolyte membrane / electrode structure 12 with a frame includes a resin frame member 24 bonded (adhered) to the stepped MEA 12a. The resin frame member 24 includes, for example, PPS (polyphenylene sulfide), PPA (polyphthalamide), PEN (polyethylene naphthalate), PES (polyethersulfone), LCP (liquid crystal polymer), PVDF (polyvinylidene fluoride), It is composed of silicone rubber, fluorine rubber, EPDM (ethylene propylene rubber), m-PPE (modified polyphenylene ether resin), or the like.

  The resin frame member 24 has a frame shape, is formed in a thin shape via a stepped portion, protrudes to the outer peripheral side of the anode electrode 22, and has an inner periphery that contacts the outer peripheral edge portion 18 be of the solid polymer electrolyte membrane 18. It has a protrusion 24a. The outer peripheral edge portion 18be of the solid polymer electrolyte membrane 18 extends outward from the outer peripheral end of the second gas diffusion layer 22b constituting the anode electrode 22.

  The inner peripheral protrusion 24a extends inward from the inner peripheral wall surface 24b with a predetermined length, and extends from the outer peripheral edge 18be of the solid polymer electrolyte membrane 18 to the tip edge of the second electrode catalyst layer 22a. It is placed over. A predetermined gap is formed between the tip of the step MEA 12a and the inner peripheral wall surface 24b.

  Between the outer peripheral edge 18be of the solid polymer electrolyte membrane 18 and the inner peripheral protrusion 24a of the resin frame member 24, a frame-shaped adhesive sheet 26 is provided. As shown in FIGS. 2 and 3, the inner peripheral edge of the adhesive sheet 26 has an overlapping portion 26 a that overlaps the surface of the outer peripheral edge of the second gas diffusion layer 22 b in the stacking direction (electrode thickness direction). The adhesive sheet 26 has an overlapping portion that is in direct contact with the second electrode catalyst layer 22a. The outer peripheral end of the adhesive sheet 26 is disposed at substantially the same position as the tips of the solid polymer electrolyte membrane 18 and the cathode electrode 20.

  For the adhesive sheet 26, for example, a thermoplastic or thermosetting adhesive is used. In the first embodiment, the adhesive sheet 26 is configured by an ester-based, acrylic-based, or urethane-based hot melt sheet. The hot melt sheet is a sheet-like adhesive that melts by heating and solidifies by cooling to obtain an adhesive force.

  As shown in FIG. 1, one end edge of the fuel cell 10 in the direction of arrow B (horizontal direction in FIG. 1) communicates with each other in the direction of arrow A, which is the stacking direction. A cooling medium inlet communication hole 32a and a fuel gas outlet communication hole 34b are provided. The oxidant gas inlet communication hole 30a supplies an oxidant gas, for example, an oxygen-containing gas, while the cooling medium inlet communication hole 32a supplies a cooling medium. The fuel gas outlet communication hole 34b discharges fuel gas, for example, hydrogen-containing gas. The oxidant gas inlet communication hole 30a, the cooling medium inlet communication hole 32a, and the fuel gas outlet communication hole 34b are arranged in the direction of arrow C (vertical direction).

  The other end edge of the fuel cell 10 in the direction of arrow B communicates with each other in the direction of arrow A, the fuel gas inlet communication hole 34a for supplying fuel gas, the cooling medium outlet communication hole 32b for discharging the cooling medium, and the oxidation An oxidant gas outlet communication hole 30b for discharging the oxidant gas is provided. The fuel gas inlet communication hole 34a, the cooling medium outlet communication hole 32b, and the oxidant gas outlet communication hole 30b are arranged in the direction of arrow C.

  An oxidant gas flow path 36 communicating with the oxidant gas inlet communication hole 30a and the oxidant gas outlet communication hole 30b is provided on the surface 16a of the second separator 16 facing the stepped electrolyte membrane / electrode structure 12. .

  A fuel gas flow path 38 communicating with the fuel gas inlet communication hole 34 a and the fuel gas outlet communication hole 34 b is formed on the surface 14 a of the first separator 14 facing the stepped electrolyte membrane / electrode structure 12. Between the surface 14 b of the first separator 14 and the surface 16 b of the second separator 16, a cooling medium flow path 40 communicating with the cooling medium inlet communication hole 32 a and the cooling medium outlet communication hole 32 b is formed.

  As shown in FIGS. 1 and 2, the first seal member 42 is integrated with the surfaces 14 a and 14 b of the first separator 14 around the outer peripheral end of the first separator 14. The second seal member 44 is integrated with the surfaces 16 a and 16 b of the second separator 16 around the outer peripheral end portion of the second separator 16.

  As shown in FIG. 2, the first seal member 42 includes a first convex seal 42 a that contacts the inner peripheral protrusion 24 a of the resin frame member 24 constituting the stepped electrolyte membrane / electrode structure 12 with a frame, and a second And a second convex seal 42b that contacts the second seal member 44 of the separator 16. The second seal member 44 constitutes a planar seal that extends in a planar shape along the separator surface. Instead of the second convex seal 42b, the second seal member 44 may be provided with a convex seal (not shown).

  For the first seal member 42 and the second seal member 44, for example, EPDM, NBR, fluororubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber or the like, cushion material Alternatively, an elastic seal member such as a packing material is used.

  As shown in FIG. 1, the first separator 14 has a supply hole portion 46 that communicates the fuel gas inlet communication hole 34a with the fuel gas passage 38, and the fuel gas passage 38 communicates with the fuel gas outlet communication hole 34b. A discharge hole 48 is formed.

  Next, a manufacturing method for manufacturing the stepped electrolyte membrane / electrode structure 12 with a frame will be described below.

  First, as shown in FIG. 4, the step MEA 12a is manufactured, and as shown in FIG. 5, the resin frame member 24 is molded by injection molding using a mold (not shown). The resin frame member 24 integrally has a thin inner protrusion 24a.

  Next, the adhesive sheet 26 made of a hot melt sheet is formed into a flat frame shape. Therefore, the adhesive sheet 26 is disposed on the inner peripheral protrusion 24 a of the resin frame member 24, and the step MEA 12 a is disposed on the inner peripheral protrusion 24 a with the adhesive sheet 26 interposed therebetween.

  As shown in FIG. 5, the outer peripheral end of the adhesive sheet 26 is set at substantially the same position as the outer peripheral end of the solid polymer electrolyte membrane 18 and the cathode electrode 20, and the inner peripheral protrusion 26 e of the adhesive sheet 26. Is set at an inner position than the outer peripheral end 22be of the second gas diffusion layer 22b.

  In this state, as shown in FIG. 6, the adhesive sheet 26 is heated and melted (hot melt) and a load (press or the like) is applied. In addition, as a bonding method using the adhesive sheet 26, a hot press or a roll press is adopted, and either single-sided heating or double-sided heating may be used.

  Therefore, the inner peripheral protrusion 24a and the solid polymer electrolyte membrane 18 are bonded, and the inner peripheral edge of the adhesive sheet 26 overlaps the surface of the outer peripheral edge of the second gas diffusion layer 22b in the stacking direction. 26a is formed. Therefore, the stepped electrolyte membrane / electrode structure 12 with a frame is manufactured.

  As shown in FIG. 2, the stepped electrolyte membrane / electrode structure 12 with a frame is sandwiched between a first separator 14 and a second separator 16. The first separator 14 abuts on the inner peripheral protrusion 24 a of the resin frame member 24 and applies a load to the stepped electrolyte membrane / electrode structure 12 with the second separator 16. Furthermore, a predetermined number of fuel cells 10 are stacked to form a fuel cell stack, and a tightening load is applied between end plates (not shown).

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

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 30a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 34a. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 32a.

  Therefore, the oxidant gas is introduced from the oxidant gas inlet communication hole 30a into the oxidant gas flow path 36 of the second separator 16, moves in the direction of arrow B, and is supplied to the cathode electrode 20 of the step MEA 12a. On the other hand, the fuel gas is introduced from the fuel gas inlet communication hole 34 a through the supply hole 46 into the fuel gas flow path 38 of the first separator 14. The fuel gas moves in the direction of arrow B along the fuel gas flow path 38 and is supplied to the anode electrode 22 of the step MEA 12a.

  Therefore, in each step MEA 12a, the oxidant gas supplied to the cathode electrode 20 and the fuel gas supplied to the anode electrode 22 are caused by an electrochemical reaction in the first electrode catalyst layer 20a and the second electrode catalyst layer 22a. It is consumed to generate electricity.

  Next, the oxidant gas consumed by being supplied to the cathode electrode 20 is discharged in the direction of arrow A along the oxidant gas outlet communication hole 30b. Similarly, the fuel gas consumed by being supplied to the anode electrode 22 passes through the discharge hole 48 and is discharged in the direction of arrow A along the fuel gas outlet communication hole 34b.

  The cooling medium supplied to the cooling medium inlet communication hole 32a is introduced into the cooling medium flow path 40 between the first separator 14 and the second separator 16, and then flows in the direction of arrow B. This cooling medium is discharged from the cooling medium outlet communication hole 32b after the step MEA 12a is cooled.

  In this case, in the first embodiment, as shown in FIG. 2, the frame-shaped adhesive sheet 26 is interposed between the inner peripheral protrusion 24a of the resin frame member 24 and the outer peripheral edge 18be of the step MEA 12a. ing. And the overlap part 26a which overlaps with the surface of the outer peripheral part of the 2nd gas diffusion layer 22b in a lamination direction is provided in the inner peripheral part of the adhesive sheet 26. As shown in FIG.

  For this reason, the resin frame member 24 and the step MEA 12a are firmly and reliably bonded via the adhesive sheet 26 as compared with a configuration in which one surface of each other is bonded. Therefore, an effect is obtained that it is possible to surely suppress the peeling between the step MEA 12a and the resin frame member 24 with a simple configuration and process.

  FIG. 7 is a cross-sectional explanatory view of a main part of a polymer electrolyte fuel cell 50 according to the second embodiment of the present invention. The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the fuel cell 50, a frame-shaped adhesive sheet 52 is provided between the outer peripheral edge 18 be of the solid polymer electrolyte membrane 18 and the inner peripheral protrusion 24 a of the resin frame member 24. The inner peripheral edge of the adhesive sheet 52 has an overlapping portion 52a that overlaps the surface of the outer peripheral edge of the second gas diffusion layer 22b in the stacking direction, and the overlapping portion 52a is the outer peripheral edge of the second gas diffusion layer 22b. Impregnated in the part. The impregnation step can be performed, for example, by an adhesion step shown in FIG. Schematically, the adhesive sheet 52 is heated and melted (hot melt) and a load (press or the like) is applied.

  Thus, in 2nd Embodiment, the resin frame member 24 and level | step difference MEA12a can be adhere | attached firmly and reliably with the adhesive sheet 52. FIG. Thereby, with the simple configuration and process, it is possible to reliably suppress the peeling between the step MEA 12a and the resin frame member 24 and the like, and the same effects as those in the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10, 50 ... Fuel cell 12 ... Stepped electrolyte membrane and electrode structure 12a with a frame ... Step MEA 14, 16 ... Separator 18 ... Solid polymer electrolyte membrane 20 ... Cathode electrode 20a, 22a ... Electrode catalyst layer 20b, 22b ... Gas diffusion Layer 22 ... Anode electrode 24 ... Resin frame member 24a, 26e ... Inner peripheral protrusion 26,52 ... Adhesive sheet 26a, 52a ... Overlapping portion 30a ... Oxidant gas inlet communication hole 30b ... Oxidant gas outlet communication hole 32a ... Cooling medium Inlet communication hole 32b ... Cooling medium outlet communication hole 34a ... Fuel gas inlet communication hole 34b ... Fuel gas outlet communication hole 36 ... Oxidant gas flow path 38 ... Fuel gas flow path 40 ... Cooling medium flow path 42, 44 ... Sealing member

Claims (4)

A first electrode having a first catalyst layer and a first gas diffusion layer is disposed on one surface of the solid polymer electrolyte membrane, and a second catalyst layer and a second electrode are disposed on the other surface of the solid polymer electrolyte membrane. A step electrolyte membrane / electrode structure in which a second electrode having two gas diffusion layers is disposed, and a planar dimension of the first gas diffusion layer is set larger than a planar dimension of the second gas diffusion layer Body,
A resin frame member having a frame shape that circulates around the outer periphery of the solid polymer electrolyte membrane, provided with an inner peripheral protrusion that is formed thinly through a step portion and protrudes toward the second gas diffusion layer; ,
A fuel cell comprising a stepped electrolyte membrane / electrode structure with a frame to which
Between the inner peripheral protrusion of the resin frame member and the outer peripheral edge of the stepped electrolyte membrane / electrode structure, a frame-shaped adhesive sheet is provided,
The fuel cell according to claim 1, wherein an inner peripheral edge portion of the adhesive sheet has an overlapping portion overlapping an outer peripheral edge surface of the second gas diffusion layer in an electrode thickness direction.   2. The fuel cell according to claim 1, wherein the overlapping portion of the adhesive sheet is impregnated in the outer peripheral edge of the second gas diffusion layer. A first electrode having a first catalyst layer and a first gas diffusion layer is disposed on one surface of the solid polymer electrolyte membrane, and a second catalyst layer and a second electrode are disposed on the other surface of the solid polymer electrolyte membrane. A step electrolyte membrane / electrode structure in which a second electrode having two gas diffusion layers is disposed, and a planar dimension of the first gas diffusion layer is set larger than a planar dimension of the second gas diffusion layer Body,
A resin frame member having a frame shape that circulates around the outer periphery of the solid polymer electrolyte membrane, provided with an inner peripheral protrusion that is formed thinly through a step portion and protrudes toward the second gas diffusion layer; ,
A method for producing a fuel cell comprising a stepped electrolyte membrane / electrode structure with a frame to which is joined,
Separately producing the stepped electrolyte membrane / electrode structure and the resin frame member;
A step of producing an adhesive sheet having a frame shape and having an inner peripheral opening dimension smaller than the outer dimension of the second gas diffusion layer;
Bonding the inner peripheral protrusion of the resin frame member and the outer peripheral edge of the stepped electrolyte membrane / electrode structure with the adhesive sheet;
A method for producing a fuel cell, comprising:   4. The method of manufacturing a fuel cell according to claim 3, further comprising a step of impregnating an inner peripheral edge of the adhesive sheet into an outer peripheral edge of the second gas diffusion layer.

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