JP2016062853A - Resin frame-attached electrolyte membrane-electrode structure for fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin frame-attached electrolyte membrane-electrode structure by which especially the formation of bubbles in an adhesive layer can be suppressed as far as possible even with a simple structure, and an electrolyte membrane-electrode structure and a resin frame member can be firmly bonded to each other with high quality.SOLUTION: A resin frame-attached electrolyte membrane-electrode structure 10 comprises: a stepped MEA 10a and a resin frame member 24 which are integrated with each other; and an adhesive layer 28 provided between the stepped MEA 10a and the resin frame member 24 by filling an adhesive 28a therein. The resin frame member 24 has a flat plane part 26b touched by the adhesive 28a; the flat plane part 26b is formed as a wrinkly textured surface 30.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electrolyte membrane / electrode structure with a resin frame for a fuel cell, comprising: a step MEA having a solid polymer electrolyte membrane sandwiched between a first electrode and a second electrode; and a resin frame member that goes around the outer periphery of the step MEA. About.

  In general, a polymer electrolyte fuel cell employs a polymer electrolyte membrane made of a polymer ion exchange membrane. The fuel cell includes an electrolyte membrane / electrode structure (MEA) in which an anode electrode is disposed on one side of the solid polymer electrolyte membrane, and a cathode electrode is disposed on the other side of the solid polymer electrolyte membrane. The anode electrode and the cathode electrode each have a catalyst layer (electrode catalyst layer) and a gas diffusion layer (porous carbon).

  The electrolyte membrane / electrode structure is sandwiched between separators (bipolar plates) to constitute a fuel cell. This fuel cell is used as, for example, an in-vehicle fuel cell stack by stacking a predetermined number of fuel cells.

  In the electrolyte membrane / electrode structure, one gas diffusion layer is set to a plane size smaller than that of the solid polymer electrolyte membrane, and the other gas diffusion layer is set to the same plane size as the solid polymer electrolyte membrane. In other words, a so-called step MEA may be formed. At that time, in order to reduce the amount of the relatively expensive solid polymer electrolyte membrane used and to protect the solid polymer electrolyte membrane having a thin film shape and low strength, an MEA with a resin frame incorporating a resin frame member is adopted. Has been.

  In the MEA with a resin frame, it is necessary to maintain a good bonding strength between the step MEA and the resin frame member in order to prevent the solid polymer electrolyte membrane from being cracked or sheared. For example, an electrolyte membrane / electrode structure with a resin frame for a fuel cell (MEA with a resin frame) disclosed in Patent Document 1 is known.

  In this MEA with a resin frame, the resin frame member has an inner peripheral bulging portion that protrudes toward the outer peripheral side of the second electrode and is adhesively bonded to the outer peripheral edge portion of the solid polymer electrolyte membrane. The adhesive bonding surface is provided with an uneven portion. For this reason, the inner peripheral bulging portion of the resin frame member can be firmly and easily bonded and bonded to the outer peripheral edge portion of the solid polymer electrolyte membrane, and the entire electrolyte membrane / electrode structure with resin frame can be bonded. The bonding strength can be reliably maintained.

JP 2013-168353 A

  The present invention has been made in connection with this type of technology, and can easily suppress the generation of bubbles in the adhesive layer with a simple configuration, and can provide an electrolyte membrane / electrode structure as much as possible. It is an object of the present invention to provide an electrolyte membrane / electrode structure with a resin frame for a fuel cell capable of bonding the resin frame member and the resin frame member firmly and with high quality.

  The electrolyte membrane / electrode structure with a resin frame for a fuel cell according to the present invention includes a step MEA and a resin frame member. In the step MEA, a first electrode is provided on one surface of the solid polymer electrolyte membrane, and a second electrode is provided on the other surface of the solid polymer electrolyte membrane. The planar dimension of the first electrode is set to be larger than the planar dimension of the second electrode. The resin frame member is provided around the outer periphery of the solid polymer electrolyte membrane.

  An adhesive layer for filling the adhesive is provided between the outer peripheral edge on the other surface side of the step MEA and the resin frame member, and the resin frame member has a surface on which the adhesive contacts. It is configured as a textured surface.

  In the electrolyte membrane / electrode structure with a resin frame for a fuel cell, it is preferable that the maximum height Rz of the uneven surface of the textured surface is 5 ≦ Rz. At this time, it is preferable that at least the skewness Rsk of the roughness curve satisfies either 0 ≦ Rsk or the kurtosis Rku of the roughness curve satisfies 3 ≦ Rku.

  According to the present invention, the adhesive disposed in the adhesive layer is stretched in the adhesive layer when the resin frame member and the step MEA are brought into close contact with each other. Here, the resin frame member is configured such that the surface with which the adhesive contacts is a textured surface. For this reason, the adhesive smoothly flows in the adhesive layer, and the air in the adhesive layer is well exhausted to the outside under the action of the embossed surface.

  Therefore, it is possible to suppress the generation of bubbles in the adhesive layer as much as possible with a simple configuration. As a result, the adhesive can be applied in a uniform thickness within the adhesive layer, and variations in quality such as gas barrier properties and adhesion durability can be suppressed. For this reason, it becomes possible to join the step MEA and the resin frame member firmly and with high quality.

It is a principal part disassembled perspective explanatory view of the polymer electrolyte fuel cell in which the resin membrane-attached 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 principal part cross-sectional explanatory drawing of the said electrolyte membrane and electrode structure with a resin frame. It is a perspective explanatory view of the resin frame member which constitutes the resin membrane-attached electrolyte membrane electrode structure. It is explanatory drawing of the method to manufacture the said electrolyte membrane-electrode structure with a resin frame. It is explanatory drawing of the method to manufacture the said electrolyte membrane-electrode structure with a resin frame. FIG. 10 is an explanatory diagram of an adhesive flow state in a resin frame member having a textured surface in which the skewness Rsk is set to a relationship of 0> Rsk. In the resin frame member of the 1st Embodiment of this invention, it is explanatory drawing of 0 <= Rsk. It is principal part cross-sectional explanatory drawing of the electrolyte membrane and electrode structure with a resin frame which concerns on the 2nd Embodiment of this invention. FIG. 5 is an explanatory view of the flow of an adhesive in a resin frame member having a crimped surface where kurtosis Rku is set to have a relationship of 3> Rku. In the resin frame member of the 2nd Embodiment of this invention, it is a flow state explanatory drawing of the said adhesive agent. It is principal part cross-sectional explanatory drawing of the electrolyte membrane and electrode structure with a resin frame which concerns on the 3rd Embodiment of this invention.

  As shown in FIGS. 1 and 2, the electrolyte membrane / electrode structure 10 with a resin frame according to the first embodiment of the present invention is incorporated into a horizontally long (or vertically long) rectangular polymer electrolyte fuel cell 12. It is. The plurality of fuel cells 12 are stacked in, for example, an arrow A direction (horizontal direction) or an arrow C direction (gravity direction) to form a fuel cell stack. The fuel cell stack is mounted on, for example, a fuel cell electric vehicle (not shown) as an in-vehicle fuel cell stack.

  In the fuel cell 12, the electrolyte membrane / electrode structure 10 with a resin frame is sandwiched between the first separator 14 and the second separator 16. The first separator 14 and the second separator 16 have a horizontally long (or vertically long) rectangular shape. 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.

  The electrolyte membrane / electrode structure 10 with a rectangular resin frame includes a step MEA 10a as shown in FIGS. The step MEA 10a includes, for example, a solid polymer electrolyte membrane (cation exchange membrane) 18 in which a perfluorosulfonic acid thin film is impregnated with water, and an anode electrode (first electrode) 20 sandwiching the solid polymer electrolyte membrane 18. And a cathode electrode (second electrode) 22. The solid polymer electrolyte membrane 18 may use an HC (hydrocarbon) based electrolyte in addition to the fluorine based electrolyte.

  The cathode electrode 22 has a smaller planar dimension than the solid polymer electrolyte membrane 18 and the anode electrode 20. Instead of the above configuration, the anode electrode 20 may be configured to have a smaller planar dimension than the solid polymer electrolyte membrane 18 and the cathode electrode 22. At that time, the anode electrode 20 becomes the second electrode, and the cathode electrode 22 becomes the first electrode.

  As shown in FIGS. 2 and 3, the anode electrode 20 includes a first electrode catalyst layer 20a bonded to one surface 18a of the solid polymer electrolyte membrane 18, and a first electrode catalyst layer 20a laminated on the first electrode catalyst layer 20a. 1 gas diffusion layer 20b is provided. The first electrode catalyst layer 20a and the first gas diffusion layer 20b have the same external dimensions and are set to the same external dimensions as (or less than) the solid polymer electrolyte membrane 18.

  The cathode electrode 22 includes a second electrode catalyst layer 22a bonded to the surface 18b of the solid polymer electrolyte membrane 18, and a second gas diffusion layer 22b stacked on the second electrode catalyst layer 22a. The second electrode catalyst layer 22 a has an outer dimension larger than that of the second gas diffusion layer 22 b and is set to an outer dimension smaller than the outer dimension of the solid polymer electrolyte membrane 18.

  The planar dimension of the second electrode catalyst layer 22a may have the same dimension as the planar dimension of the second gas diffusion layer 22b, or the planar dimension of the second electrode catalyst layer 22a may be the second dimension. You may have a dimension smaller than the plane dimension of the gas diffusion layer 22b.

  The first electrode catalyst layer 20a is formed, for example, by uniformly applying porous carbon particles having a platinum alloy supported on the surface thereof to the surface of the first gas diffusion layer 20b. The second electrode catalyst layer 22a is formed, for example, by uniformly applying porous carbon particles carrying a platinum alloy on the surface thereof to the surface of the second gas diffusion layer 22b. The first gas diffusion layer 20b and the second gas diffusion layer 22b are made of carbon paper, carbon cloth, or the like, and the planar dimension of the second gas diffusion layer 22b is smaller than the planar dimension of the first gas diffusion layer 20b. Is set. The first electrode catalyst layer 20a and the second electrode catalyst layer 22a are formed on both surfaces of the solid polymer electrolyte membrane 18, for example.

  The resin membrane-attached electrolyte membrane / electrode structure 10 includes a resin frame member 24 that circulates around the outer periphery of the solid polymer electrolyte membrane 18 and is joined to the anode electrode 20 and the cathode electrode 22. 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. In addition, the resin frame member 24 may be made of PET (polyethylene terephthalate), PBT (polybutylene terephthalate), or modified polyolefin.

  As shown in FIGS. 1 and 4, the resin frame member 24 has a frame shape. As shown in FIGS. 2 and 3, the resin frame member 24 has an inner bulging portion 24 a formed in a thin shape that bulges from the inner peripheral base end portion 24 s to the cathode electrode 22 side. The inner bulging portion 24a extends from the inner peripheral base end portion 24s inward (in the direction of arrow C) to have a predetermined length, and extends from the outer peripheral edge portion 18bt of the solid polymer electrolyte membrane 18 to the second electrode catalyst layer 22a. And it arrange | positions in the vicinity of outer peripheral edge part 22ae and 22be of the 2nd gas diffusion layer 22b. The outer peripheral edge 18bt of the solid polymer electrolyte membrane 18 is exposed outward in the plane direction from the tip of the cathode electrode 22.

  The inner bulging portion 24a is continuous with the inner peripheral base end portion 24s, and is a convex portion that contacts the outer peripheral edge portion of the step MEA 10a, specifically, the distal end side of the first electrode catalyst layer 20a constituting the anode electrode 20. 26a is provided. The convex portion 26a is formed in a frame shape that goes around the tip side of the first electrode catalyst layer 20a. A flat surface portion 26b formed thinner than the convex portion 26a via a step portion 26ae is provided at an inner end portion of the convex portion 26a, and the flat surface portion 26b is formed on the inner side from the convex portion 26a. It extends to the inner peripheral edge of the bulging portion 24a.

  An adhesive layer 28 filled with an adhesive 28a is provided between the outer peripheral edge 18bt on the surface 18b side of the step MEA 10a and the resin frame member 24. As the adhesive 28a, for example, a polymer or a fluorine-based elastomer is provided. In addition, as an adhesive agent, it is not restrict | limited to liquid, solid, thermoplasticity, thermosetting, etc.

  The resin frame member 24 has a surface that contacts the adhesive 28 a, that is, a flat surface portion 26 b as a textured surface 30. In the first embodiment, as will be described later, the embossed surface 30 has a maximum unevenness height Rz (JIS standard) of 5 ≦ Rz and a roughness curve skewness (distortion degree) Rsk (JIS standard). ) Is set to a relationship of 0 ≦ Rsk.

  As shown in FIG. 2, the resin frame member 24 and the first gas diffusion layer 20b of the anode electrode 20 are integrated by a resin impregnated portion 32 using an adhesive resin. The resin-impregnated portion 32 can be configured, for example, by thermally deforming a resin protrusion 32t that is integrally formed with the resin frame member 24. The resin impregnated portion 32 may use an adhesive 28 a in the same manner as the adhesive layer 28.

  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. A cooling medium inlet communication hole 42a and a fuel gas outlet communication hole 44b are provided. The oxidant gas inlet communication hole 40a supplies an oxidant gas, for example, an oxygen-containing gas, while the cooling medium inlet communication hole 42a supplies a cooling medium. The fuel gas outlet communication hole 44b discharges a fuel gas, for example, a hydrogen-containing gas. The oxidant gas inlet communication hole 40a, the cooling medium inlet communication hole 42a, and the fuel gas outlet communication hole 44b are arranged in an arrow 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, the fuel gas inlet communication hole 44a for supplying fuel gas, the cooling medium outlet communication hole 42b for discharging the cooling medium, and the oxidation An oxidizing gas outlet communication hole 40b for discharging the oxidizing gas is provided. The fuel gas inlet communication hole 44a, the cooling medium outlet communication hole 42b, and the oxidant gas outlet communication hole 40b are arranged in the direction of arrow C.

  An oxidant gas flow path 46 communicating with the oxidant gas inlet communication hole 40a and the oxidant gas outlet communication hole 40b is provided on the surface 16a of the second separator 16 facing the electrolyte membrane / electrode structure 10 with a resin frame. .

  A fuel gas passage 48 communicating with the fuel gas inlet communication hole 44a and the fuel gas outlet communication hole 44b is formed on the surface 14a of the first separator 14 facing the electrolyte membrane / electrode structure 10 with a resin frame. A cooling medium flow path 50 communicating with the cooling medium inlet communication hole 42a and the cooling medium outlet communication hole 42b is formed between the surface 14b of the first separator 14 and the surface 16b of the second separator 16 adjacent to each other. .

  As shown in FIGS. 1 and 2, the first seal member 52 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 54 is integrated with the surfaces 16 a and 16 b of the second separator 16 around the outer peripheral end of the second separator 16.

  As shown in FIG. 2, the first seal member 52 includes a first convex seal 52 a that contacts the resin frame member 24 constituting the electrolyte membrane / electrode structure 10 with a resin frame, and a second seal of the second separator 16. And a second convex seal 52b that contacts the member 54. The second seal member 54 constitutes a flat seal in which a surface that contacts the second convex seal 52b extends in a flat shape along the separator surface. Instead of the second convex seal 52b, the second seal member 54 may be provided with a convex seal (not shown).

  For the first seal member 52 and the second seal member 54, for example, EPDM, NBR, fluoro rubber, 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.

  Next, a method for manufacturing the electrolyte membrane / electrode structure 10 with a resin frame will be described below.

  First, the step MEA 10a is manufactured, while the resin frame member 24 is injection-molded using a mold (not shown). In the step MEA 10a, a first gas diffusion layer 20b and a second gas diffusion layer 22b are formed by applying a slurry made of a mixture of carbon black and PTFE particles on a flat surface of carbon paper and drying to form a base layer. Is formed.

  On the other hand, after adding a solvent to the electrode catalyst, a binder solution is added to prepare a cathode electrode ink and an anode electrode ink. Cathode electrode ink is applied to a PET film by screen printing to form a cathode electrode sheet. Similarly, the anode electrode ink is applied to a PET film by screen printing to form an anode electrode sheet.

  Next, hot pressing is performed in a state where the solid polymer electrolyte membrane 18 is sandwiched between the cathode electrode sheet and the anode electrode sheet, and then the PET film is peeled to form a joined body (CCM). Further, the CCM is sandwiched between the first gas diffusion layer 20b and the second gas diffusion layer 22b and integrated by hot pressing to form the step MEA 10a.

  Moreover, as shown in FIG. 4, the resin frame member 24 has a thin inner bulging portion 24a. The inner bulging portion 24a is provided with a convex portion 26a continuous to the inner peripheral base end portion 24s, and is formed thinner at the inner end portion of the convex portion 26a than the convex portion 26a. A flat surface portion 26b is provided. A resin protrusion 32t is integrally formed on the resin frame member 24 as necessary.

  The injection-molded resin frame member 24 is subjected to a texture processing on the flat surface portion 26b to form a textured surface 30. The embossing can be performed using, for example, a plasma apparatus. On the other hand, although not shown, the embossed surface 30 may be formed at the time of injection molding of the resin frame member 24 by providing an uneven shape corresponding to the embossed surface 30 on the molding surface of the injection mold. .

  Next, as shown in FIG. 5, the adhesive 28a is applied to the resin frame member 24 on the surface of the inner bulging portion 24a on the adhesive layer 28 side through, for example, a dispenser (not shown). Furthermore, the inner peripheral base end 24s of the resin frame member 24, the outer peripheral end 20be of the first gas diffusion layer 20b constituting the step MEA 10a, and the outer peripheral end 18e of the solid polymer electrolyte membrane 18 are aligned.

  As shown in FIG. 6, the adhesive 28a is heated and a load (press or the like) is applied in the thickness direction. For this reason, the adhesive 28 a is pressurized and melted, and the adhesive 28 a is stretched in the adhesive layer 28. Therefore, the inner bulging portion 24 a of the resin frame member 24 and the outer peripheral edge portion 18 bt of the solid polymer electrolyte membrane 18 are bonded via the adhesive layer 28.

  Further, the inner peripheral surface of the inner peripheral end 24 ae of the resin frame member 24 and the front end surface of the outer peripheral end 22 be of the second gas diffusion layer 22 b are bonded via an adhesive layer 28. On the other hand, the resin frame member 24 and the first gas diffusion layer 20 b of the anode electrode 20 are integrated by the resin impregnated portion 32. Therefore, the electrolyte membrane / electrode structure 10 with a resin frame is manufactured.

  In this case, in the first embodiment, the surface of the resin frame member 24 that is in contact with the adhesive 28 a is configured as a textured surface 30. For this reason, when the adhesive 28a flows through the adhesive layer 28, the air in the adhesive layer 28 moves along the flow of the adhesive 28a and is well exhausted to the outside.

  At that time, the embossed surface 30 has a maximum unevenness height Rz of 5 ≦ Rz. Accordingly, the embossed surface 30 can exhibit a sufficient anchor effect as an adhesive surface. On the other hand, the solid polymer electrolyte membrane 18 has a thickness of 20 μm to 30 μm. For this reason, if the maximum height Rz has a relationship of 20 <Rz, the solid polymer electrolyte membrane 18 may be bent in a bowl shape. Accordingly, it is preferable that the relationship 5 ≦ Rz ≦ 20 is set.

  Furthermore, in the first embodiment, the textured surface 30 is set such that the skewness Rsk of the roughness curve is 0 ≦ Rsk. FIG. 7 shows a resin frame member 24comp. Having a textured surface 30comp. In which the skewness Rsk is set to a relationship of 0> Rsk. In the embossed surface 30comp., A gap 58comp. Is formed between the protrusions 56comp., And the gap 58comp. Has a tapered shape inward.

  Accordingly, the adhesive 28a adheres to the wall surface of the adjacent protrusion 56comp. Before flowing inward (back side) of the gap 58comp., And air easily remains in the gap 58comp. Moreover, since the gap 58comp. Has a tapered shape toward the back side, the movement resistance of the adhesive 28a increases as it goes to the back side. For this reason, it is difficult for the adhesive 28a to flow into the back side of the gap 58comp., And there is a problem that air remains and bubbles are generated.

  On the other hand, in the first embodiment, the skewness Rsk is set to a relationship of 0 ≦ Rsk. As a result, as shown in FIG. 8, the embossed surface 30 has a plurality of tapered projections 56, and a relatively wide gap 58 is formed between the projections 56. Therefore, the problem of the textured surface 30comp. Can be solved.

  For this reason, in the first embodiment, it is possible to suppress the generation of bubbles in the adhesive layer 28 as much as possible with a simple configuration, and the adhesive 28a is uniformly thickened in the adhesive layer 28. It becomes possible to apply it. Thereby, it is possible to suppress the occurrence of variations in quality such as gas barrier properties and adhesion durability, and it is possible to join the step MEA 10a and the resin frame member 24 firmly and with high quality. can get.

  The operation of the fuel cell 12 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 40a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 44a. Supplied. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 42a.

  Therefore, the oxidant gas is introduced from the oxidant gas inlet communication hole 40a into the oxidant gas flow path 46 of the second separator 16, moves in the direction of arrow B, and is supplied to the cathode electrode 22 of the step MEA 10a. On the other hand, the fuel gas is introduced into the fuel gas channel 48 of the first separator 14 from the fuel gas inlet communication hole 44a. The fuel gas moves in the direction of arrow B along the fuel gas channel 48 and is supplied to the anode electrode 20 of the step MEA 10a.

  Therefore, in each step MEA 10a, the oxidant gas supplied to the cathode electrode 22 and the fuel gas supplied to the anode electrode 20 are electrochemically reacted in the second electrode catalyst layer 22a and the first electrode catalyst layer 20a. It is consumed and power is generated.

  Next, the oxidant gas supplied and consumed to the cathode electrode 22 is discharged in the direction of arrow A along the oxidant gas outlet communication hole 40b. Similarly, the fuel gas consumed by being supplied to the anode electrode 20 is discharged in the direction of arrow A along the fuel gas outlet communication hole 44b.

  In addition, the cooling medium supplied to the cooling medium inlet communication hole 42 a is introduced into the cooling medium flow path 50 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 42b after cooling the step MEA 10a.

  FIG. 9 is an explanatory cross-sectional view of a main part of an electrolyte membrane / electrode structure 60 with a resin frame according to the second embodiment of the present invention. In addition, the same referential mark is attached | subjected to the component same as the electrolyte membrane and electrode structure 10 with a resin frame which concerns on 1st Embodiment, and the detailed description is abbreviate | omitted. Similarly, in the third embodiment described below, detailed description thereof is omitted.

  The electrolyte membrane / electrode structure 60 with a resin frame is configured by integrating the step MEA 10 a and the resin frame member 62. The resin frame member 62 configures the flat surface portion 26 b as a textured surface 64. The embossed surface 64 has a maximum height Rz (JIS standard) of irregularities of 5 ≦ Rz, and the kurtosis (kurtosis) Rku (JIS standard) of the roughness curve is set to a relationship of 3 ≦ Rku. .

  FIG. 10 shows a resin frame member 62comp. Having a textured surface 64comp. In which Kurtosis Rku is set to have a relationship of 3> Rku. In the embossed surface 64comp., A gap 68comp. Is formed between the protrusions 66comp., And the gap 68comp. Has an inclined surface sf with a steep inner inclination angle.

  Therefore, the adhesive 28a does not easily flow inward (back side) of the gap 68comp., And air easily remains in the gap 68comp. For this reason, there is a problem that air remains in the back side of the gap 68comp.

  On the other hand, in the second embodiment, the kurtosis Rku is set to a relationship of 3 ≦ Rku. As a result, as shown in FIG. 11, the embossed surface 64 has a plurality of tapered protrusions 66, and a gap 68 that is relatively complicatedly curved is formed between the protrusions 66 via the stepped portion. ing. Therefore, the portion where the adhesive 28a is difficult to enter in the gap 68 is reduced, and the above-mentioned problem of the textured surface 64comp. Can be solved.

  For this reason, the second embodiment has the same effects as those of the first embodiment, such as being able to suppress the generation of bubbles in the adhesive layer 28 as much as possible with a simple configuration. can get. The first embodiment and the second embodiment can be adopted at the same time. That is, the textured surface 64 has a maximum unevenness height Rz of 5 ≦ Rz (≦ 20), a skewness Rsk of the roughness curve has a relationship of 0 ≦ Rsk, and the roughness curve The kurtosis Rku can satisfy the relationship of 3 ≦ Rku.

  FIG. 12 is an explanatory cross-sectional view of a main part of an electrolyte membrane / electrode structure 70 with a resin frame according to the third embodiment of the present invention.

  The electrolyte membrane / electrode structure 70 with a resin frame includes a step MEA 10 a and a resin frame member 72. The resin frame member 72 is formed in a film shape, and the maximum thickness is set to the thickness of the convex portion 26a.

  The third embodiment configured as described above has advantages that the same effects as those of the first and second embodiments described above can be obtained, and that the resin frame member 72 can be easily reduced in thickness.

DESCRIPTION OF SYMBOLS 10, 60, 70 ... Resin-framed electrolyte membrane and electrode structure 10a ... Step MEA 12 ... Fuel cell 14, 16 ... Separator 18 ... Solid polymer electrolyte membrane 18bt ... Outer peripheral edge part 18e, 20be, 22ae, 22be ... Outer peripheral edge Part 20 ... Anode electrode 20a, 22a ... Electrocatalyst layer 20b, 22b ... Gas diffusion layer 22 ... Cathode electrodes 24, 62, 72 ... Resin frame member 24a ... Inner bulging part 24s ... Inner peripheral base end part 26a ... Convex part 26b ... Flat surface portion 28 ... Adhesive layer 28a ... Adhesive 30, 64 ... Wrinkled surface 32t ... Resin protrusion 40a ... Oxidant gas inlet communication hole 40b ... Oxidant gas outlet communication hole 42a ... Cooling medium inlet communication hole 42b ... Cooling medium Outlet communication hole 44a ... Fuel gas inlet communication hole 44b ... Fuel gas outlet communication hole 46 ... Oxidant gas channel 48 ... Fuel gas channel 50 ... Coolant flow channel 5 2, 54 ... Sealing member

Claims (2)

A first electrode is provided on one surface of the solid polymer electrolyte membrane, a second electrode is provided on the other surface of the solid polymer electrolyte membrane, and the planar dimensions of the first electrode are A step MEA set to a dimension larger than the planar dimension of the second electrode;
A resin frame member provided around the outer periphery of the solid polymer electrolyte membrane;
An electrolyte membrane / electrode structure with a resin frame for a fuel cell comprising:
Between the outer peripheral edge portion on the other surface side of the step MEA and the resin frame member, an adhesive layer for filling an adhesive is provided,
An electrolyte membrane / electrode structure with a resin frame for a fuel cell, wherein the resin frame member has a surface that contacts the adhesive as a textured surface. 2. The electrolyte membrane / electrode structure with a resin frame for a fuel cell according to claim 1, wherein the embossed surface has a maximum unevenness height Rz of 5 ≦ Rz,
Electrolyte membrane / electrode structure with a resin frame for a fuel cell, wherein at least the skewness Rsk of the roughness curve satisfies either 0 ≦ Rsk or the kurtosis Rku of the roughness curve satisfies 3 ≦ Rku body.

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