JP6784492B2 - Manufacturing method of MEA with resin frame - Google Patents

Description

The present invention is a method for manufacturing a MEA with a resin frame for a fuel cell, which comprises a step MEA in which a solid polymer electrolyte membrane is sandwiched between a first electrode and a second electrode, and a resin frame member bonded to the outer periphery of the step MEA. Regarding.

Generally, a polymer electrolyte fuel cell employs a solid polymer electrolyte membrane made of a polymer ion exchange membrane. A fuel cell is provided with an electrolyte membrane / electrode structure (MEA) in which an anode electrode is arranged on one surface of a solid polymer electrolyte membrane and a cathode electrode is arranged on the other surface of the solid polymer electrolyte membrane. There is. 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 form a power generation cell (unit fuel cell). By stacking a predetermined number of power generation cells, for example, they are used in a fuel cell electric vehicle as an in-vehicle fuel cell stack.

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

For example, an electrolyte membrane / electrode structure with a resin frame disclosed in Patent Document 1 is known. In this electrolyte membrane / electrode structure with a resin frame, the outer peripheral edge portion of the solid polymer electrolyte membrane, which is the step portion side of the step MEA, and the inner peripheral protrusion portion, which is the step portion side of the resin frame member, are attached to each other by an adhesive. It is fixed.

Japanese Unexamined Patent Publication No. 2014-017150

By the way, when the adhesive is applied to the outer peripheral edge of the solid polymer electrolyte membrane, the adhesion reaction between the adhesive and the solid polymer electrolyte membrane proceeds with the passage of time. Therefore, when the solid polymer electrolyte membrane and the resin frame member are crimped to spread the adhesive, it is clear between the portion where the adhesive reaction has progressed (reaction region) and the unreacted portion (unreacted region). Interfaces may occur. Therefore, when the adhesive is pressurized and heated to cure and an adhesive layer is formed, there is a problem that the adhesive layer is easily peeled off at the interface and the adhesive strength is lowered.

The present invention solves this kind of problem, and an adhesive for adhering a solid polymer electrolyte film and a resin frame member by not forming a reaction region in the adhesive layer is applied to the solid polymer electrolyte film. intended to be applied only to the outer peripheral surface in comparison with the case where spread the adhesive, to provide a method of manufacturing the stepped MEA and resin frame member bonding strength enables Rukoto enhance resin framed MEA And.

The present invention relates to a method for manufacturing a MEA with a resin frame for a fuel cell having a stepped MEA and a resin frame member. In the step MEA, 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 a flat surface of the first electrode is provided. The dimensions are set to be larger than the plane dimensions of the second electrode.

The second electrode is provided on the catalyst layer with the outer peripheral surface of the solid polymer electrolyte membrane exposed and the catalyst layer provided on the other surface, and the gas provided on the catalyst layer with the outer peripheral surface of the catalyst layer exposed. It has a diffusion layer. The resin frame member is bonded to the outer peripheral surface of the solid polymer electrolyte membrane exposed to the outside of the second electrode with an adhesive .

In this production method, the first electrode is provided on the one surface of the solid polymer electrolyte membrane, and the catalyst layer is provided on the other surface of the solid polymer electrolyte membrane from the outer peripheral end of the gas diffusion layer. After the first step of manufacturing the step MEA, the second step of molding the resin frame member, and the first step by projecting the outer peripheral surface of the above and providing the second electrode, the solid height After the third step of applying the adhesive only to the outer peripheral surface of the catalyst layer so that the adhesive is not applied to the outer peripheral surface of the molecular electrolyte membrane, and the second step and the third step, the step. By stacking the MEA and the resin frame member, applying pressure and heating, the adhesive is allowed to flow from the outer peripheral surface of the catalyst layer onto the outer peripheral surface of the solid polymer electrolyte membrane, and the solid polymer is allowed to flow. a fourth step of forming an adhesive layer for bonding the outer peripheral surface and the resin frame member of the electrolyte membrane, that having a.

Further, in this manufacturing method, in the third step, the adhesive has a first adhesive line arranged on the catalyst layer in contact with the outer peripheral end surface of the gas diffusion layer, and an outer peripheral end of the catalyst layer on the catalyst layer. It is preferably applied to the second adhesive line arranged in the portion.

Further, in this manufacturing method, the portion of the adhesive applied to the first adhesive line protrudes from the resin frame member on the side opposite to the solid polymer electrolyte membrane during the fourth step. It is preferable that there is no such thing.
Furthermore, in the fourth step, it is preferable that the outer peripheral surface of the solid polymer electrolyte membrane is provided with a non-bonding region in which the adhesive does not exist.

According to the present invention, in the third step, the adhesive is a catalyst that projects outward from the outer peripheral edge of the gas diffusion layer constituting the second electrode so that the adhesive is not applied to the outer peripheral surface of the solid polymer electrolyte membrane. It is applied only to the outer peripheral surface of the layer. Then, in the fourth step, an adhesive is allowed to flow from the outer peripheral surface of the catalyst layer onto the outer peripheral surface of the solid polymer electrolyte membrane to form an adhesive layer that joins the outer peripheral surface of the solid polymer electrolyte membrane and the resin frame member. ing. Therefore , a reaction region is not formed in the adhesive layer . Therefore, as compared with the case where the adhesive for adhering the solid polymer electrolyte membrane and the resin frame member is applied only to the outer peripheral surface of the solid polymer electrolyte membrane and the adhesive is spread out , the step MEA and the resin can Rukoto enhance the adhesive strength between the frame member.

It is a main part disassembled perspective explanatory view of the solid polymer type power generation cell which incorporates MEA with a resin frame to which the manufacturing method of this invention is applied. FIG. 1 is a cross-sectional explanatory view taken along line II-II of the power generation cell in FIG. It is explanatory drawing at the time of forming the CCM constituting the MEA with a resin frame in the said manufacturing method. It is explanatory drawing at the time of applying the adhesive to the step MEA in the 1st manufacturing method. It is explanatory drawing at the time of joining the resin frame member to the step MEA in the 1st manufacturing method. It is explanatory drawing at the time of applying the adhesive to the step MEA in the manufacturing method of the comparative example. It is explanatory drawing at the time of joining the resin frame member to the step MEA in the manufacturing method of the said comparative example. It is explanatory drawing at the time of applying the adhesive to the step MEA in the 2nd manufacturing method. It is explanatory drawing at the time of joining the resin frame member to the step MEA in the 2nd manufacturing method. It is explanatory drawing of the relationship between a joint area and peeling durability. It is sectional drawing of the main part of another MEA with a resin frame.

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

The power generation cell 12 sandwiches the MEA 10 with a resin frame between the anode separator 14 and the cathode separator 16. The anode separator 14 and the cathode separator 16 have a horizontally long (or vertically long) rectangular shape. The anode separator 14 and the cathode 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 metal surface is surface-treated for corrosion protection, a carbon member, or the like.

The rectangular MEA10 with a resin frame includes a stepped MEA10a. As shown in FIG. 2, the step MEA10a is, for example, an anode electrode (first electrode) sandwiching the solid polymer electrolyte membrane 18 which is a thin film of perfluorosulfonic acid containing water and the solid polymer electrolyte membrane 18. It has 20 and a cathode electrode (second electrode) 22. The solid polymer electrolyte membrane 18 is a cation exchange membrane, and an HC (hydrocarbon) -based electrolyte may be used in addition to the fluorine-based electrolyte.

The cathode electrode 22 has a plane dimension (external dimension) smaller than that of the solid polymer electrolyte membrane 18 and the anode electrode 20, and the solid polymer electrolyte membrane 18 and the anode electrode 20 have the same plane dimension. Instead of the above configuration, the anode electrode 20 may be configured to have a plane dimension smaller than that of 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 FIG. 2, the anode electrode 20 has a first electrode catalyst layer 20a bonded to one surface 18a of the solid polymer electrolyte membrane 18 and a first gas diffusion laminated on the first electrode catalyst layer 20a. A layer 20b is provided. The first electrode catalyst layer 20a and the first gas diffusion layer 20b have the same planar dimensions (external dimensions) and are set to the same (or less than the same) planar dimensions as the solid polymer electrolyte membrane 18. The first electrode catalyst layer 20a may be set to a smaller plane size (or a larger plane size) than the first gas diffusion layer 20b.

The cathode electrode 22 is provided with a second electrode catalyst layer 22a and a second gas diffusion layer 22b. The second electrode catalyst layer 22a is joined to the surface 18b of the solid polymer electrolyte membrane 18 in a state where the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 is exposed. The second gas diffusion layer 22b is laminated on the second electrode catalyst layer 22a in a state where the outer peripheral surface 22ae of the second electrode catalyst layer 22a is exposed. The second electrode catalyst layer 22a has a plane dimension larger than the plane dimension of the second gas diffusion layer 22b, and is set to a plane dimension smaller than the plane dimension of the solid polymer electrolyte membrane 18.

The first electrode catalyst layer 20a is formed, for example, by uniformly coating the surface of the first gas diffusion layer 20b with porous carbon particles on which a platinum alloy is supported. The second electrode catalyst layer 22a is formed, for example, by uniformly coating the surface of the second gas diffusion layer 22b with porous carbon particles on which a platinum alloy is supported.

The first gas diffusion layer 20b is formed of a microporous layer 20b (m) having porosity and conductivity, and a carbon layer 20b (c) such as carbon paper or carbon cloth. The second gas diffusion layer 22b is formed of a microporous layer 22b (m) having porosity and conductivity, and a carbon layer 22b (c) such as carbon paper or carbon cloth. The plane dimension of the second gas diffusion layer 22b is set smaller than the plane dimension of the first gas diffusion layer 20b.

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. The microporous layers 20b (m) and 22b (m) may be provided as needed, and may be eliminated.

The MEA 10 with a resin frame includes a film-shaped resin frame member (resin molded body or resin film) 24 having a uniform thickness on the entire surface joined to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. The inner peripheral end surface 24e of the resin frame member 24 and the outer peripheral end surface 22be of the second gas diffusion layer 22b of the cathode electrode 22 are separated from each other.

The resin frame member 24 includes, for example, PPS (polyphenylene terephide), PPA (polyphthalamide), PEN (polyethylene terephthalate), PES (polyether sulfone), LCP (liquid crystal polymer), PVDF (polybutylene terephite), and the like. It is composed of silicone resin, fluororesin, m-PPE (modified polyphenylene ether resin), PET (polyethylene terephthalate), PBT (polybutylene terephthalate), modified polyolefin and the like.

The resin frame member 24 is provided with an adhesive surface 24a bonded to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. An adhesive layer 26 made of, for example, an adhesive 26a such as a liquid fluoroelastomer is provided between the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 and the adhesive surface 24a of the resin frame member 24.

An adhesive layer 26s made of an adhesive 26a is located on the second electrode catalyst layer 22a between the inner peripheral end surface 24e of the resin frame member 24 and the outer peripheral end surface 22be of the second gas diffusion layer 22b of the cathode electrode 22. Provided. The adhesive layer 26 retains the bonding strength between the step MEA 10a and the resin frame member 24, and the adhesive layer 26s prevents the second electrode catalyst layer 22a from coming into contact with the outside air. The adhesive layer 26 and the adhesive layer 26s may be connected to each other.

As shown in FIG. 1, one end edge portion of the power generation cell 12 in the arrow B direction (horizontal direction in FIG. 1) is individually communicated in the arrow A direction, which is the stacking direction, and is an oxidant gas inlet communication hole. 30a, 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 a fuel gas, for example, a 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 arrow C direction (vertical direction).

At the other end of the power generation cell 12 in the direction of arrow B, a fuel gas inlet communication hole 34a for supplying fuel gas, a cooling medium outlet communication hole 32b for discharging the cooling medium, and a cooling medium outlet communication hole 32b, which communicate individually in the direction of arrow A, respectively. And 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.

The outer peripheral end of the resin frame member 24 has an oxidant gas inlet communication hole 30a, a cooling medium inlet communication hole 32a, a fuel gas outlet communication hole 34b, a fuel gas inlet communication hole 34a, a cooling medium outlet communication hole 32b, and an oxidizer gas outlet communication hole. Each communication hole is not formed so as to be located inside the hole 30b.

A plurality of oxidant gas flow paths extending in the direction of arrow B communicating with the oxidant gas inlet communication hole 30a and the oxidant gas outlet communication hole 30b on the surface 16a of the cathode separator 16 toward the resin framed MEA10. 36 is provided.

A plurality of fuel gas flow paths 38 extending in the direction of arrow B are formed on the surface 14a of the anode separator 14 toward the MEA10 with a resin frame, which communicates with the fuel gas inlet communication hole 34a and the fuel gas outlet communication hole 34b. Will be done. Between the surface 14b of the anode separator 14 and the surface 16b of the cathode separator 16 adjacent to each other, a plurality of lines communicating with the cooling medium inlet communication hole 32a and the cooling medium outlet communication hole 32b and extending in the arrow B direction. The cooling medium flow path 40 is formed.

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

As shown in FIG. 2, the first seal member 42 has a first convex seal 42a that abuts on the resin frame member 24 constituting the MEA 10 with a resin frame, and a second seal member 42 that abuts on the second seal member 44 of the cathode separator 16. It has a convex seal 42b. The first seal member 42 has a third convex seal 42c and a fourth convex seal 42d that project to the opposite side of the resin frame member 24.

The second seal member 44 constitutes a flat seal in which the surface in contact with the second convex seal 42b extends in a plane along the separator surface. In addition, instead of the second convex seal 42b, a convex seal (not shown) may be provided on the second seal member 44.

The first sealing member 42 and the second sealing member 44 include, for example, a sealing material such as EPDM, NBR, fluororubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroplane or acrylic rubber, and a cushioning material. Alternatively, an elastic sealing member such as a packing material is used.

Next, the manufacturing method according to the first embodiment of the present invention for manufacturing the MEA10 with a resin frame will be described below.

While the step MEA10a is produced, the resin frame member 24 is prepared by cutting a film (for example, a PPS sheet) into a frame shape with a Thomson blade. In order to prepare the stepped MEA10a, first, a slurry composed of a mixture of carbon black and PTFE (polytetrafluoroethylene) particles is applied to a flat surface of a carbon layer 20b (c) made of carbon paper, and dried. A microporous layer 20b (m), which is a stratum, is formed.

The first gas diffusion layer 20b is formed by joining the carbon layer 20b (c) to the microporous layer 20b (m). Similarly, the microporous layer 22b (m) is formed, and the carbon layer 22b (c) is bonded to the microporous layer 22b (m) to form the second gas diffusion layer 22b.

On the other hand, after adding the solvent to the electrode catalyst, for example, a solution of a perfluoroalkylene sulfonic acid polymer compound is added as an ionic conductive polymer binder solution. Then, the anode electrode ink and the cathode electrode ink are produced by adding the solvent until the ink has a predetermined viscosity.

Therefore, as shown in FIG. 3, the anode electrode ink is applied to the PET film 50a by screen printing and heat-dried to form the anode electrode sheet 52 provided with the first electrode catalyst layer 20a. The first electrode catalyst layer 20a is set to have the same planar dimensions as the solid polymer electrolyte membrane 18.

Similarly, the cathode electrode ink is applied to the PET film 50b by screen printing and heat-dried to form a cathode electrode sheet 54 provided with the second electrode catalyst layer 22a. The second electrode catalyst layer 22a is set to a plane size smaller than that of the solid polymer electrolyte membrane 18.

Next, the hot press is performed with the solid polymer electrolyte membrane 18 sandwiched between the anode electrode sheet 52 and the cathode electrode sheet 54. Then, the PET films 50a and 50b are peeled off to form a bonded film (CCM) (catalyst coated membrane).

Further, the first gas diffusion layer 20b and the second gas diffusion layer 22b sandwich a CCM between the microporous layers 20b (m) and 22b (m), and are integrated by hot pressing to form a step MEA10a. (See FIG. 2). At that time, on the surface 18b of the solid polymer electrolyte membrane 18, the outer peripheral surface 22ae of the second electrode catalyst layer 22a is exposed from the outer peripheral end portion of the second gas diffusion layer 22b, and the outer peripheral surface of the solid polymer electrolyte membrane 18 is exposed. 18be is exposed from the outer peripheral end portion of the second electrode catalyst layer 22a.

As shown in FIG. 4, the step MEA10a is arranged so that the cathode electrode 22 faces upward. The outer peripheral surface 22ae of the second electrode catalyst layer 22a is coated with two adhesive lines by a liquid adhesive 26aa and a liquid adhesive 26ab using a dispenser (not shown) over the entire circumference.

The adhesive 26aa is coated along the first adhesive line with a predetermined width dimension h1 so as to be in contact with the outer peripheral end surface 22be of the second gas diffusion layer 22b. The adhesive 26ab is coated along the second adhesive line at a position close to the outer peripheral end of the second electrode catalyst layer 22a with a predetermined width dimension h2. The width dimension h2 of the adhesive 26ab is set to a value larger than the width dimension h1 of the adhesive 26aa (h1 <h2).

Next, as shown in FIG. 5, the resin frame member 24 is arranged on the step MEA10a, and is pressurized and heat-treated by a servo press machine (not shown). Therefore, the adhesive 26aa flows between the inner peripheral end surface 24e of the resin frame member 24 and the outer peripheral end surface 22be of the cathode electrode 22, while the adhesive 26ab is solid from the outer peripheral end portion of the second electrode catalyst layer 22a. It flows on the outer peripheral surface 18be of the polymer electrolyte membrane 18. Therefore, the adhesive 26aa is cured to form the adhesive layer 26s, and the adhesive 26ab is cured to form the adhesive layer 26, so that the MEA10 with a resin frame is manufactured (see FIG. 2).

Therefore, the test piece obtained by cutting the MEA10 with a resin frame into a strip shape was immersed in water at 90 ° C. for 3000 hours and then left at 23 ° C. for 12 hours in an environment of 50% RH. Further, after the first gas diffusion layer 20b was peeled off, a test piece from which the second gas diffusion layer 22b was peeled off was obtained, and the end of the resin frame member 24 and the end of the CCM were obtained by an autograph manufactured by Shimadzu Corporation. The portions were individually gripped and a peel strength of 180 ° was measured.

On the other hand, as shown in FIG. 6, a comparison piece was created by the comparison step MEA10a (ref.). In the comparative piece, the adhesive 26a (ref.) Is applied on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 with a predetermined width dimension h2 over a region close to the outer peripheral end of the second electrode catalyst layer 22a. It was constructed. Other manufacturing steps are the same as those in the first embodiment described above. As a result, the peel strength of the test piece was 3 times or more the peel strength of the comparative piece.

Specifically, in the comparative piece, as shown in FIG. 6, the adhesive 26a (ref.) Is coated on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. Therefore, in the adhesive 26a (ref.), The reaction at the contact portion with the outer peripheral surface 18be gradually progresses, and the reaction region 56 is generated.

Next, as shown in FIG. 7, when the resin frame member 24 is pressurized and heat-treated on the step MEA10a (ref.), The adhesive 26a (ref.) Spreads on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. It is being pushed out. At that time, the flowing adhesive 26a (ref.) And the reaction region 56 may be clearly separated, and a clear interface 58 may be formed between them. Therefore, when the adhesive 26a (ref.) Is pressurized and heated to cure and the adhesive layer 26 is formed, the adhesive layer 26 is easily peeled off at the interface 58, and the adhesive strength is lowered. ..

On the other hand, in the first embodiment, as shown in FIG. 4, when the step MEA 10a and the resin frame member 24 are joined by the adhesive 26ab, the adhesive 26ab is applied to the outer periphery of the second electrode catalyst layer 22a. It is applied to the surface 22ae. As a result, the contact time between the adhesive 26ab and the solid polymer electrolyte membrane 18 can be shortened as much as possible, and variations in the adhesive quality can be reduced. Therefore, the effect that the step MEA 10a and the resin frame member 24 can be firmly and surely adhered to each other can be obtained by a simple process.

Next, the operation of the power generation cell 12 configured in this way 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. Be supplied. 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 into the oxidant gas flow path 36 of the cathode separator 16 from the oxidant gas inlet communication hole 30a, 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 flow path 38 of the anode separator 14 from the fuel gas inlet communication hole 34a. 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 step MEA10a.

Therefore, in the step MEA 10a, the oxidant gas supplied to the cathode electrode 22 and the fuel gas supplied to the anode electrode 20 are consumed by the electrochemical reaction in the second electrode catalyst layer 22a and the first electrode catalyst layer 20a. And power is generated.

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

Further, the cooling medium supplied to the cooling medium inlet communication hole 32a is introduced into the cooling medium flow path 40 between the anode separator 14 and the cathode separator 16 and then flows in the direction of arrow B. After cooling the step MEA10a, the cooling medium is discharged from the cooling medium outlet communication hole 32b.

Next, the manufacturing method according to the second embodiment of the present invention for manufacturing the MEA10 with a resin frame will be described below. In the second embodiment, it is manufactured in the same manner as in the first embodiment described above, and detailed description of the same steps will be omitted.

As shown in FIG. 8, the outer peripheral surface 22ae of the second electrode catalyst layer 22a is coated with two adhesive lines by a liquid adhesive 26aa and a liquid adhesive 26ac using a dispenser (not shown) over the entire circumference. Work is done.

The adhesive 26ac is applied along the second adhesive line with a predetermined width dimension h3 (h1 <h3) from the outer peripheral surface 22ae of the second electrode catalyst layer 22a to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. Is done. At that time, the adhesive area S1 applied to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 is the adhesive area S2 (see FIG. 9) between the solid polymer electrolyte membrane 18 and the resin frame member 24 on the outer peripheral surface 18be. It is set to 60% or less of.

Further, as shown in FIG. 9, the resin frame member 24 and the step MEA10a are pressurized and heat-treated. Therefore, the adhesive 26aa flows between the inner peripheral end surface 24e of the resin frame member 24 and the outer peripheral end surface 22be of the cathode electrode 22, while the adhesive 26ac flows on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18. It flows toward the outer peripheral edge.

In this case, a part of the adhesive 26ac (adhesive area S1) is previously coated on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18, and the reaction region 56 is generated with the passage of time. .. Therefore, when the adhesive 26ac is spread on the outer peripheral surface 18be of the solid polymer electrolyte membrane 18, an interface 58 is formed between the flowing adhesive 26ac and the reaction region 56.

Here, in the second embodiment, the adhesive area S1 applied in advance to the outer peripheral surface 18be of the solid polymer electrolyte membrane 18 is set to 60% or less of the adhesive area S2 on the outer peripheral surface 18be. As a result, the solid polymer electrolyte membrane 18 and the resin frame member 24 can maintain a bonding region having a high bonding strength of 40% or more of the bonding area S2, and the peeling of the adhesive layer 26 can be satisfactorily suppressed. Becomes possible.

FIG. 10 shows the relationship between the bonding region {(adhesive area S2-adhesive area S1) / adhesive area S2} × 100% of the adhesive layer 26 and the peeling durability. The peeling durability is the ratio of the peel strength in each joint region when the peel strength when the joint region is 100% is 100.

As shown in FIG. 10, when the bonding region is 40% or more, that is, the adhesive area S1 is 60% or less of the adhesive area S2, good peel strength can be maintained. Therefore, the same effect as that of the first embodiment can be obtained, such that the step MEA 10a and the resin frame member 24 can be firmly and surely adhered by a simple process.

FIG. 11 is a cross-sectional explanatory view of a main part of another MEA (electrolyte film / electrode structure) 80 with a resin frame to which the manufacturing method of the present invention is applied. The same components as the MEA10 with a resin frame are designated by the same reference numerals, and detailed description thereof will be omitted.

The MEA80 with a resin frame includes a step MEA80a and a resin frame member 82, and the step MEA80a and the resin frame member 82 are joined by an adhesive layer 26.

The resin frame member 82 is provided with an outer peripheral portion 82a having a rectangular frame shape and having a thickness substantially the same as the thickness of the step MEA80a (dimension in the direction of arrow A). The outer peripheral portion 82a is provided with an inner bulging portion 82b formed in a thin wall shape that bulges from the inner peripheral base end portion 82s to the cathode electrode 22 side via a step portion. The inner bulging portion 82b extends inward from the inner peripheral base end portion 82s with a predetermined length, and is arranged so as to cover the outer peripheral surface 18be of the solid polymer electrolyte membrane 18.

The MEA80 with a resin frame configured as described above is manufactured by the manufacturing method according to the first and second embodiments. Therefore, the same effect as when the MEA10 with a resin frame is used can be obtained.

10, 80 ... MEA with resin frame 10a, 80a ... Step MEA
12 ... Power generation cells 14, 16 ... Separator 18 ... Solid polymer electrolyte membrane 18be ... Outer surface 20 ... Anode electrodes 20a, 22a ... Electrode catalyst layers 20b, 22b ... Gas diffusion layer 22 ... Cathode electrodes 24, 82 ... Resin frame member 24a ... Adhesive surface 26, 26s ... Adhesive layer 26a ... Adhesive 30a ... Oxidizing gas inlet communication hole 30b ... Oxidizing agent gas outlet communication hole 32a ... Cooling medium inlet communication hole 32b ... Cooling medium outlet communication hole 34a ... Fuel gas inlet communication hole 34a ... Hole 34b ... Fuel gas outlet communication hole 36 ... Oxidizing agent gas flow path 38 ... Fuel gas flow path 40 ... Cooling medium flow path 42, 44 ... Seal member

Claims (4)

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 plane dimensions of the first electrode are the above. The second electrode is set to a size larger than the plane dimension of the second electrode, and the second electrode is provided with a catalyst layer and the catalyst layer provided on the other surface in a state where the outer peripheral surface of the solid polymer electrolyte membrane is exposed. A step MEA provided with a gas diffusion layer provided on the catalyst layer with the outer peripheral surface of the surface exposed.
A resin frame member bonded to the outer peripheral surface of the solid polymer electrolyte membrane exposed to the outside of the second electrode by an adhesive.
It is a manufacturing method of MEA with a resin frame for a fuel cell having
The first electrode is provided on the one surface of the solid polymer electrolyte membrane, and the outer peripheral surface of the catalyst layer is provided on the other surface of the solid polymer electrolyte membrane from the outer peripheral end of the gas diffusion layer. The first step of manufacturing the step MEA by projecting and providing the second electrode, and
The second step of molding the resin frame member and
After the first step, a third step of applying the adhesive only to the outer peripheral surface of the catalyst layer so that the adhesive is not applied to the outer peripheral surface of the solid polymer electrolyte membrane .
After the second step and the third step, the step MEA and the resin frame member are overlapped with each other, and by pressurizing and heating the adhesive, the adhesive is applied from the outer peripheral surface of the catalyst layer to the solid polymer electrolyte. production of the outer peripheral surface and the fourth step and, that having a resin frame with MEA to form an adhesive layer for junction and the resin frame member of the by flowing solid polymer electrolyte film on the outer peripheral surface of the film Method. The production method according to claim 1, wherein in the third step, the adhesive is arranged on the catalyst layer in contact with the outer peripheral end surface of the gas diffusion layer, and on the catalyst layer. A method for producing a MEA with a resin frame , which is applied to a second adhesive line arranged at the outer peripheral end of the catalyst layer. The manufacturing method according to claim 2.
Of the adhesive, the portion applied to the first adhesive line does not protrude from the resin frame member to the side opposite to the solid polymer electrolyte membrane during the fourth step, and is a MEA with a resin frame. Production method. The manufacturing method according to any one of claims 1 to 3.
A method for producing a MEA with a resin frame, wherein in the fourth step, a non-bonding region in which the adhesive does not exist is provided on the outer peripheral surface of the solid polymer electrolyte membrane.

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