JP2013258097A - Electrolyte membrane/electrode structure and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure excellent power generation performance by blocking damage on a solid polymer electrolyte membrane as much as possible, with simple and economical configuration and process.SOLUTION: An electrolyte membrane/electrode structure 10 includes an anode electrode 20 and a cathode electrode 22 sandwiching a solid polymer electrolyte membrane 18, and the anode electrode 20 is set with plane dimensions smaller than those of the cathode electrode 22. In the solid polymer electrolyte membrane 18, a reinforcement film 24 is provided on the outer peripheral surface 18ae projecting outward of the anode electrode 20. The reinforcement film 24 has a frame-like shape, and a portion 24e folding from the solid polymer electrolyte membrane 18, in a direction separating therefrom, is provided at an inner peripheral part facing the anode electrode 20.

Description

  The present invention relates to an electrolyte membrane / electrode structure in which electrodes are disposed on both sides of a solid polymer electrolyte membrane, and a method for producing the same.

  In general, a polymer electrolyte fuel cell employs a polymer electrolyte membrane made of a polymer ion exchange membrane. This fuel cell comprises an electrolyte membrane / electrode structure (MEA) in which an anode electrode and a cathode electrode each comprising a catalyst layer (electrode catalyst) and a gas diffusion layer (porous carbon) are disposed on both sides of a solid polymer electrolyte membrane. ) Is sandwiched between separators (bipolar plates). Usually, a fuel cell stack in which a predetermined number of the fuel cells are stacked is used.

  In the above electrolyte membrane / electrode structure, a thin-film solid polymer electrolyte membrane is used. Therefore, it is necessary to prevent the solid polymer electrolyte membrane from being damaged by the differential pressure of the reaction gas applied to the solid polymer electrolyte membrane or mechanical stress.

  Thus, for example, a solid polymer electrolyte fuel cell disclosed in Patent Document 1 is known. As shown in FIG. 10, this fuel cell is composed of an electrolyte membrane 1 made of a solid polymer, a catalyst layer 2 that becomes an electrode, and a frame-shaped protective film 3 that is formed so as to surround the catalyst layer 2. A membrane-electrode assembly (MEA) 4 is provided. Furthermore, the protective film 3 and the diffusion layer 5 are joined via the adhesive layer 7.

JP 2004-319153 A

  By the way, in the above Patent Document 1, the inner peripheral side (opening side) corner 3e of the frame-shaped protective film 3 is disposed on the electrolyte membrane 1. For this reason, when the fuel cell is assembled or when a load is applied to the fuel cell during operation, the inner peripheral corner 3e of the protective film 3 may be pushed into the electrolyte membrane 1. Therefore, damage such as a decrease in the thickness of the electrolyte membrane 1 occurs, and there is a problem that the durability of the electrolyte membrane 1 is lowered.

  The present invention solves this type of problem, and it is possible to prevent damage to the solid polymer electrolyte membrane as much as possible with a simple and economical configuration and process, and to ensure good power generation performance. An object of the present invention is to provide an electrolyte membrane / electrode structure and a method for producing the same.

  In the present invention, electrodes are disposed on both surfaces of a solid polymer electrolyte membrane, and the solid polymer electrolyte membrane has a larger planar dimension than at least one electrode, and has a frame shape on the outer periphery of the one electrode. The present invention relates to an electrolyte membrane / electrode structure provided with a reinforcing film and a manufacturing method thereof.

  In this electrolyte membrane / electrode structure, the reinforcing film is provided with a folded portion that is folded back in a direction away from the solid polymer electrolyte membrane at an inner peripheral portion facing one electrode.

  Further, in this electrolyte membrane / electrode structure, it is preferable that a notch portion for folding is provided in the inner peripheral portion of the reinforcing film.

  Furthermore, in this electrolyte membrane / electrode structure, it is preferable that one electrode has a smaller planar dimension than the other electrode, and the reinforcing film is provided only on the one electrode side.

  Furthermore, this manufacturing method includes a step of providing electrodes on both sides of the solid polymer electrolyte membrane, and a folding back in a direction away from the solid polymer electrolyte membrane on the inner peripheral portion facing one electrode of the reinforcing film. And a step of bonding a reinforcing film to the one electrode side of the solid polymer electrolyte membrane.

  Moreover, in this manufacturing method, it is preferable that the inner peripheral part of a reinforcement film is provided with the cut | notch part for folding.

  Further, in this manufacturing method, the electrolyte membrane / electrode structure is a stepped electrolyte membrane / electrode structure in which one electrode has a smaller planar dimension than the other electrode, and the reinforcing film is disposed only on the one electrode side. It is preferable to be provided.

  According to the present invention, the reinforcing film is provided with the folded portion that is folded back in the direction away from the solid polymer electrolyte membrane. For this reason, the corner | angular part of a reinforcement film does not contact a solid polymer electrolyte membrane directly, but can suppress being pushed into the said solid polymer electrolyte membrane reliably.

  Thus, it is only necessary to provide a folded portion at the end of the reinforcing film, and to prevent damage to the solid polymer electrolyte membrane as much as possible with a simple and economical configuration and process, and to ensure good power generation performance. Is possible.

It is a principal part disassembled perspective explanatory view of the fuel cell in which the electrolyte membrane / electrode structure according to the first embodiment of the present invention is incorporated. FIG. 2 is a sectional view of the fuel cell taken along line II-II in FIG. 1. It is explanatory drawing of the preparation operation | work of the reinforcement film which comprises the said electrolyte membrane electrode structure. It is a disassembled perspective explanatory drawing of the folding apparatus which performs the folding process on the said reinforcement film. It is side surface explanatory drawing of the said folding device. It is operation | movement explanatory drawing of the said folding | turning apparatus. It is an isometric view explanatory drawing of the film member in which the folding process was performed. It is a principal part disassembled perspective explanatory view of the fuel cell in which the electrolyte membrane / electrode structure according to the second embodiment of the present invention is incorporated. FIG. 9 is a sectional view of the fuel cell taken along line IX-IX in FIG. 8. 2 is an explanatory diagram of a fuel cell disclosed in Patent Document 1. FIG.

  As shown in FIG. 1, an electrolyte membrane / electrode structure 10 according to a first embodiment of the present invention is incorporated in a fuel cell 12. For example, an in-vehicle fuel cell stack is configured by stacking a plurality of fuel cells 12 in the direction of arrow A (for example, the horizontal direction).

  In the fuel cell 12, the electrolyte membrane / electrode structure 10 is sandwiched between the first separator 14 and the 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 plated steel plate, a metal plate whose surface is subjected to corrosion prevention, a carbon member, or the like. .

  As shown in FIG. 2, the electrolyte membrane / electrode structure 10 includes a solid polymer electrolyte membrane 18, an anode electrode (one electrode) 20 and a cathode electrode (the other electrode) that sandwich the solid polymer electrolyte membrane 18. 22. The anode electrode 20 has a smaller planar dimension (surface area) than the cathode electrode 22, and the solid polymer electrolyte membrane 18 has a frame-like outer peripheral surface 18 a exposed from the outer periphery of the anode electrode 20 to the reinforcing film 24. Is disposed.

  The anode electrode 20 is in contact with one surface 18a of the solid polymer electrolyte membrane 18, and the first electrode catalyst layer 20a and the first gas diffusion layer that expose the outer peripheral surface 18ae of the solid polymer electrolyte membrane 18 in a frame shape. 20b is provided. The cathode electrode 22 is provided with a second electrode catalyst layer 22 a and a second gas diffusion layer 22 b that are in contact with the other surface 18 b of the solid polymer electrolyte membrane 18. The first electrode catalyst layer 20a and the second electrode catalyst layer 22a may be composed of a plurality of layers.

  The planar dimension of the second gas diffusion layer 22b is set to be larger than the planar dimension of the first gas diffusion layer 20b, and the second gas diffusion layer 22b protrudes from the outer periphery of the second electrode catalyst layer 22a and has a solid height. The entire other surface 18b of the molecular electrolyte membrane 18 is covered.

  The first gas diffusion layer 20b protrudes from the outer periphery of the first electrode catalyst layer 20a, and on the outer peripheral surface 18ae of the solid polymer electrolyte membrane 18 exposed outward from the end of the first gas diffusion layer 20b. A reinforcing film 24 is provided. The reinforcing film 24 is made of, for example, a PEN (polyethylene naphthalate) film and has a thickness of about 10 μm to 200 μm.

  In addition, the reinforcing film 24 is made of PPS (polyphenylene sulfide resin), PEEK (polyether ether ketone), PES (polyether sulfone), PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), or the like. May be. Also, ABS (thermoplastic resin made of acrylonitrile, butadiene, styrene), PBT (polybutylene terephthalate), LCP (liquid crystal polymer) or PP (polypropylene) may be used, or a mixture thereof may be used. Good.

  The reinforcing film 24 has a frame shape (frame shape), and a folded portion 24 e that is folded back in a direction away from the solid polymer electrolyte membrane 18 is provided in an inner peripheral portion facing the anode electrode 20. The reinforcing film 24 is adhered to the outer peripheral surface 18ae of the solid polymer electrolyte membrane 18 by an adhesive 26, and the adhesive 26 is applied to the folded portion 24e as necessary. The folded portion 24e has a length S of about 1 mm to 5 mm, for example.

  The inner peripheral surface of the folded portion 24e contacts the outer peripheral end of the first gas diffusion layer 20b, and an R (curved surface) is formed on the inner peripheral surface. The folded portion 24e is folded with a cut portion 50, which will be described later, inside. In addition, the folding | returning part 24e may be folded by making a recessed part (not shown) into the outer side (inner peripheral surface).

  As shown in FIG. 1, one end edge of the fuel cell 12 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, An oxidant gas inlet communication hole 30a for supplying gas, a cooling medium inlet communication hole 32a for supplying a cooling medium, and a fuel gas outlet communication hole 34b for discharging a fuel gas, for example, a hydrogen-containing gas, are shown by arrows. Arranged in the C direction (vertical direction).

  The other end edge of the fuel cell 12 in the direction of arrow B communicates with each other in the direction of arrow A, a fuel gas inlet communication hole 34a for supplying fuel gas, and a cooling medium outlet communication hole for discharging the cooling medium. 32b and an oxidant gas outlet communication hole 30b for discharging the oxidant gas are arranged in the direction of arrow C.

  An oxidant gas flow path 36 that communicates 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 electrolyte membrane / electrode structure 10.

  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 electrolyte membrane / electrode structure 10. 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, and the second The second seal member 44 is integrated with the surfaces 16 a and 16 b of the separator 16 around the outer peripheral end of the second separator 16.

  As shown in FIG. 2, the first seal member 42 includes a first convex seal 42 a interposed between the reinforcing film 24 and the first separator 14, and the first separator 14 and the second separator 16. And a second convex seal 42b interposed therebetween. The second seal member 44 constitutes a flat seal. Instead of the second convex seal 42b, the second seal member 44 may be provided with a second convex seal (not shown).

  The first and second sealing members 42 and 44 include, for example, EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber, a cushioning 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 electrolyte membrane / electrode structure 10 will be described below.

  First, as will be described later, a so-called step MEA 10a is produced in which one gas diffusion layer has a larger planar dimension than the other gas diffusion layer. Specifically, an ion conductive solution is introduced into a mixture of a catalyst and a solvent, and an electrode paste obtained by coating a uniformly mixed electrode paste on a PET sheet made of a PET film by screen printing is formed. Hot pressing is performed with the solid polymer electrolyte membrane 18 sandwiched therebetween.

  Then, the first electrode catalyst layer 20a and the second electrode catalyst layer 22a are formed on the surface 18a and the surface 18b of the solid polymer electrolyte membrane 18 by peeling the PET sheet. Thereby, an electrolyte membrane with a catalyst is formed.

  In addition, a large size carbon paper (hereinafter also referred to as a large CP) corresponding to the first gas diffusion layer 20b and a small size carbon paper (hereinafter also referred to as a small CP) corresponding to the second gas diffusion layer 22b. Produced. Then, a slurry in which a mixture containing carbon black and PTFE (polytetrafluoroethylene) particles is uniformly dispersed in ethylene glycol is formed. The slurry is applied to the large CP and the small CP and dried, whereby the first gas diffusion layer 20b composed of the large CP and the base layer and the second gas diffusion layer 22b composed of the small CP and the base layer. Is produced.

  Furthermore, the first gas diffusion layer 20b and the second gas diffusion layer 22b are disposed on both sides of the electrolyte membrane with catalyst, and hot pressing is performed. For this reason, the step MEA 10a is obtained.

  On the other hand, the reinforcing film 24 is produced. For example, a PEN film is processed to obtain a frame-shaped (frame-shaped) film member 24F (see FIG. 3). In the film member 24F, a plurality of cut portions 50 are formed along the turn-back position, and cuts 52 are formed at the respective inner peripheral corner portions and cut by a predetermined length toward the respective outer peripheral corner portions. The cut portions 50 are intermittently arranged on the surface of the film member 24F along the long direction and the short direction.

  Note that the cut portion 50 may be continuously formed on the surface of the film member 24F. This is because it can be easily bent straight along the notch 50.

  As shown in FIGS. 4 and 5, the film member 24 </ b> F is folded by a folding device 54. The folding device 54 includes a convex jig 56 corresponding to the inner peripheral shape of the folding portion 24e of the film member 24F, a pressing jig 58 that holds the film member 24F against the convex jig 56, and the film. The member 24F includes folding plates 60a and 60b that form the folding portion 24e.

  The convex jig 56 has a substantially rectangular shape, and a trapezoidal tip 56a is provided on the upper side. A plurality of guide groove portions 56b are formed on both sides of the long side of the convex jig 56, extending in the vertical direction and parallel to each other. On both sides of the short side of the convex jig 56, a plurality of guide groove portions 56c are formed extending in the vertical direction and in parallel with each other.

  The holding jig 58 has a frame shape (frame shape), and the inner peripheral shape is set to a size larger than the outer shape of the convex jig 56. The holding jig 58 presses and holds the outer peripheral edge of the film member 24F (see FIG. 5).

  As shown in FIG. 4, the folded plates 60a and 60b have a thin comb-tooth shape. The folded plate 60 a is provided with a number of guide portions 60 aa corresponding to the guide groove portions 56 b of the convex jig 56. The folded plate 60 b is provided with a number of guide portions 60 bb corresponding to the guide groove portions 56 c of the convex jig 56. Note that only the single folded plate 60b may be used without using the folded plate 60a.

  Therefore, as shown in FIG. 5, the film member 24 </ b> F has the convex jig 56 disposed in the internal space, and the outer peripheral edge is pressed and held by the pressing jig 58. The inner peripheral edge of the film member 24 </ b> F is supported upward by contacting each side of the convex jig 56.

  In this state, for example, the pair of folded plates 60 a are disposed in the guide groove portions 56 b on both long sides of the convex jig 56, while the pair of folded plates 60 b are disposed on both short sides of the convex jig 56. It arrange | positions in the guide groove part 56c.

  Further, as shown in FIG. 6, the folded plate 60 a is inclined in a direction away from the convex jig 56 (direction of arrow T). For this reason, the inner peripheral edge portion of the film member 24F is bent in the direction of the arrow T by the guide portion 60aa of the folding plate 60a to form the folded portion 24e. Similarly, when the other folded plates 60a and 60b are inclined outward, the folded portion 24e is formed around the inner periphery of the film member 24F (see FIG. 7).

  Next, after the adhesive 26 is applied to the film member 24F, the film member 24F is disposed on the step MEA 10a. The reinforcing film 24 is bonded to the outer peripheral surface 18ae of the solid polymer electrolyte membrane 18 by the adhesive 26 by heating and pressurizing, whereby the electrolyte membrane / electrode structure 10 is manufactured.

  In this case, in the first embodiment, as shown in FIG. 2, the reinforcing film 24 is provided with a folded portion 24 e that is folded back in a direction away from the solid polymer electrolyte membrane 18. Accordingly, the corners of the reinforcing film 24 are folded back on the reinforcing film 24 and do not come into direct contact with the solid polymer electrolyte membrane 18 and are reliably suppressed from being pushed into the solid polymer electrolyte membrane 18. can do.

  As a result, it is only necessary to provide the folded portion 24e at the end of the reinforcing film 24, and it is possible to prevent damage to the solid polymer electrolyte membrane 18 as much as possible with a simple and economical configuration and process. The effect that it becomes possible to ensure is obtained.

  In addition, although the folding | returning part 24e is bend | folded along the some notch part 50, after providing a notch, you may fold, or you may make it deform | transform by heat and bend | fold.

  The operation of the fuel cell 12 incorporating the electrolyte membrane / electrode structure 10 thus configured 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.

  For this reason, the oxidant gas is introduced into the oxidant gas flow path 36 of the second separator 16 from the oxidant gas inlet communication hole 30a and moves in the direction of arrow B to the cathode electrode 22 of the electrolyte membrane / electrode structure 10. Supplied. 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 20 of the electrolyte membrane / electrode structure 10.

  Therefore, in each electrolyte membrane / electrode structure 10, the oxidant gas supplied to the cathode electrode 22 and the fuel gas supplied to the anode electrode 20 are in the first electrode catalyst layer 20a and the second electrode catalyst layer 22a. Power is generated by being consumed by electrochemical reaction.

  Next, the oxidant gas consumed by being supplied to the cathode electrode 22 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 20 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. The cooling medium is discharged from the cooling medium outlet communication hole 32b after the electrolyte membrane / electrode structure 10 is cooled.

  As shown in FIGS. 8 and 9, the electrolyte membrane / electrode structure 70 according to the second embodiment of the present invention is incorporated in a fuel cell 72. The same components as those of the electrolyte membrane / electrode structure 10 and the fuel cell 12 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the fuel cell 72, the electrolyte membrane / electrode structure 70 is sandwiched between the first separator 74 and the second separator 76. Although the 1st separator 74 and the 2nd separator 76 are comprised with a carbon separator, for example, it may replace with this carbon separator and may be comprised with a metal thin plate, for example.

  As shown in FIG. 9, the electrolyte membrane / electrode structure 70 includes an MEA 70a. The MEA 70a includes, for example, a solid polymer electrolyte membrane 18 in which a thin film of perfluorosulfonic acid is impregnated with water, An anode electrode 20 and a cathode electrode 22 sandwiching the molecular electrolyte membrane 18 are included. The anode electrode 20 and the cathode electrode 22 are set to have the same planar dimensions, and the outer peripheral surfaces 18ae and 18be of the solid polymer electrolyte membrane 18 are more outward than the outer peripheral end portions of the anode electrode 20 and the cathode electrode 22. Extend to.

  Reinforcing films 24 a and 24 b are provided on the outer peripheral surfaces 18 ae and 18 be of the solid polymer electrolyte membrane 18. The reinforcing films 24a and 24b are configured similarly to the reinforcing film 24 described above.

  The reinforcing film 24 a has a frame shape (frame shape), and a folded portion 24 ae that is folded back in a direction away from the solid polymer electrolyte membrane 18 is provided in an inner peripheral portion facing the anode electrode 20. The reinforcing film 24a is adhered to the outer peripheral surface 18ae of the solid polymer electrolyte membrane 18 by an adhesive 26a, and the adhesive 26a is applied to the folded portion 24ae as necessary.

  The reinforcing film 24b has a frame shape (frame shape), and a folded portion 24be that is folded back in a direction away from the solid polymer electrolyte membrane 18 is provided in an inner peripheral portion facing the cathode electrode 22. The reinforcing film 24b is adhered to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 by an adhesive 26b, and an adhesive 26b is applied to the folded portion 24be as necessary.

  In the second embodiment configured as described above, the electrolyte membrane / electrode structure 70 is manufactured by the same process as in the first embodiment.

  Moreover, the reinforcing films 24 a and 24 b are provided with folded portions 24 ae and 24 be that are folded back in a direction away from the solid polymer electrolyte membrane 18. Accordingly, the corners of the reinforcing films 24a and 24b are folded back on the reinforcing films 24a and 24b, and are not directly in contact with the solid polymer electrolyte membrane 18, but are pushed into the solid polymer electrolyte membrane 18. Can be reliably suppressed.

  Thereby, it is only necessary to provide the folded portions 24ae and 24be at the ends of the reinforcing films 24a and 24b, and the damage to the solid polymer electrolyte membrane 18 is prevented as much as possible with a simple and economical configuration and process. The same effects as those in the first embodiment can be obtained, such as ensuring good power generation performance.

10, 70 ... Electrolyte membrane / electrode structure 10a ... Step MEA
DESCRIPTION OF SYMBOLS 12, 72 ... Fuel cell 14, 16, 74, 76 ... Separator 18 ... Solid polymer electrolyte membrane 18ae ... Outer peripheral surface 20 ... Anode electrode 20b, 22b ... Gas diffusion layer 20a, 22a ... Electrode catalyst layer 22 ... Cathode electrode 24, 24a, 24b: Reinforcing films 24e, 24ae, 24be ... Folded portion 24F ... Film members 26, 26a, 26b ... Adhesive 36 ... Oxidant gas flow path 38 ... Fuel gas flow path 40 ... Cooling medium flow path 42, 44 ... Seal Member 50 ... Cut section 52 ... Cut 54 ... Folding device 56 ... Convex jigs 60a, 60b ... Folding plate 70a ... MEA

Claims (6)

Electrodes are disposed on both sides of the solid polymer electrolyte membrane, the solid polymer electrolyte membrane has a larger planar dimension than at least one of the electrodes, and a frame-shaped reinforcing film is provided on the outer periphery of the one electrode. An electrolyte membrane / electrode structure provided,
The electrolyte membrane / electrode structure according to claim 1, wherein the reinforcing film is provided with a folded portion that is folded back in a direction away from the solid polymer electrolyte membrane at an inner peripheral portion facing the one electrode.   2. The electrolyte membrane / electrode structure according to claim 1, wherein the inner peripheral portion of the reinforcing film is provided with a cut-in portion for folding. The electrolyte membrane / electrode structure according to claim 1 or 2, wherein the one electrode has a smaller planar dimension than the other electrode,
The electrolyte membrane / electrode structure according to claim 1, wherein the reinforcing film is provided only on the one electrode side. Electrodes are disposed on both sides of the solid polymer electrolyte membrane, the solid polymer electrolyte membrane has a larger planar dimension than at least one of the electrodes, and a frame-shaped reinforcing film is provided on the outer periphery of the one electrode. A method for producing an electrolyte membrane / electrode structure to be provided,
Providing the electrodes on both sides of the solid polymer electrolyte membrane;
A step of providing a folded portion by folding back in a direction away from the solid polymer electrolyte membrane on an inner peripheral portion of the reinforcing film facing the one electrode;
Bonding the reinforcing film to the one electrode side of the solid polymer electrolyte membrane;
A method for producing an electrolyte membrane / electrode structure, comprising:   5. The method of manufacturing an electrolyte membrane / electrode structure according to claim 4, wherein the inner peripheral portion of the reinforcing film is provided with a cut-in portion for folding. 6. The manufacturing method according to claim 4, wherein the electrolyte membrane / electrode structure is a stepped electrolyte membrane / electrode structure in which the one electrode has a smaller planar dimension than the other electrode.
The method for producing an electrolyte membrane / electrode structure, wherein the reinforcing film is provided only on the one electrode side.

Images