JP3524274B2 - Method and apparatus for manufacturing an assembly in which electrodes are provided on both surfaces of a solid polymer electrolyte membrane - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for manufacturing an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane.

[0002]

2. Description of the Related Art Usually, an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane is used for a fuel cell, an electrolytic treatment device for salt water,
Alternatively, it is used in ozone generators and the like. For example, a fuel cell constituted by stacking a plurality of fuel cell structures in which an anode-side electrode and a cathode-side electrode are opposed to each other with a solid polymer electrolyte membrane sandwiched by a separator has been developed, and has been used in various applications. It is being put to practical use.

In this type of fuel cell, for example, hydrogen gas (fuel gas) produced by steam reforming of methanol is supplied to the anode electrode and oxidant gas (air) is supplied to the cathode electrode. With this, the hydrogen gas is ionized and flows in the solid polymer electrolyte membrane, whereby electric energy is obtained outside.

By the way, in the above fuel cell, a solid polymer electrolyte membrane is sandwiched between two catalyst electrodes (gas diffusion electrodes), and an operation of integrating them by hot pressing is performed. However, it has been pointed out that when hot pressing is performed at a temperature of 100 ° C. or higher, water in the solid polymer electrolyte membrane is likely to evaporate, which causes the solid polymer electrolyte membrane to deteriorate.

Therefore, the manufacturing method disclosed in Japanese Patent Laid-Open No. 3-295171 is adopted. In this manufacturing method, as shown in FIG. 5, spacers 5a and 5b having openings 3a and 3b corresponding to the catalyst electrodes 4a and 4b arranged on both surfaces of the solid polymer electrolyte membrane 2 are prepared, The spacers 5a and 5b are interposed between the solid polymer electrolyte membrane 2 and the rubber sheets 6a and 6b. Therefore, the catalyst electrodes 4a, 4b are pressed through the press dies 8a, 8b.
When joining the both sides of the solid polymer electrolyte membrane 2, the spacer 5 prevents the water from evaporating from the solid polymer electrolyte membrane 2.
It can be blocked by a and 5b.

[0006]

However, in the above conventional method, the pressure applied by the press dies 8a, 8b is dispersed not only on the catalyst electrodes 4a, 4b but also on the spacers 5a, 5b side. As a result, the pressure applied to the catalyst electrodes 4a, 4b is reduced, and there is a problem that defective fusion between the catalyst electrodes 4a, 4b and the solid polymer electrolyte membrane 2 is caused. At that time, an attempt is made to increase the pressurizing time to avoid defective fusion between the catalyst electrodes 4a and 4b and the solid polymer electrolyte membrane 2, but this makes the cycle time longer and It has been pointed out that the quality of the solid polymer electrolyte membrane 2 deteriorates due to evaporation of water from the solid polymer electrolyte membrane 2.

The present invention solves this kind of problem, effectively preventing evaporation of water from the solid polymer electrolyte membrane, and surely bonding electrodes to both surfaces of the solid polymer electrolyte membrane. An object of the present invention is to provide a method and an apparatus for manufacturing an assembly in which electrodes are provided on both surfaces of a solid polymer electrolyte membrane capable of being manufactured.

[0008]

In order to solve the above-mentioned problems, the present invention has a surface area larger than that of a solid polymer electrolyte membrane on both sides.
Together when the solid polymer electrolyte membrane disposed a small electrode is held by the first and second frame, the water is sealed inside the first and second frame, the solid polymer electrolyte membrane It is maintained in a predetermined wet condition. Then, the press parts are respectively inserted into both openings formed in the first and second frames.
And the electrodes are bonded to both surfaces of the solid polymer electrolyte membrane by heating and pressurizing both electrodes through only the openings through the inserted press parts .

As described above, the solid polymer electrolyte membrane and the electrodes are sandwiched between the first and second frames, and the first and second frames are filled with water. For this reason,
It is possible to prevent the moisture in the solid polymer electrolyte membrane from evaporating to the outside of the first and second frames during the heat treatment, and moreover, the moisture in the solid polymer electrolyte membrane of the first and second frames is prevented. Never escape inside. Therefore, the solid polymer electrolyte membrane can always be reliably maintained in a desired wet state.

Further, since the heating and pressurizing treatment is applied to the electrode only through the opening, the pressing force is not dispersed to the electrodes other than this electrode and the desired pressing force is surely applied to the electrode. be able to.

Further, after the electrodes are joined to both surfaces of the solid polymer electrolyte membrane, the heating press die is forcibly cooled before releasing the pressing force of the heating press die. Therefore, the pressing force is not released when the hot press die is in a high temperature state, and it is possible to effectively prevent a defect such as damage to the solid polymer electrolyte membrane due to the pressure of water vapor.

Furthermore, the hot pressing means has a tapered surface on the side of the pressing portion inserted into the opening, which is inclined inward in the direction away from the electrode. As a result, a space is provided between the first and second frames and the side portion of the press portion, and the heat of the press portion is applied to the first and second portions.
It is possible to prevent the escape to the frame side.

[0013]

FIG. 1 is an exploded perspective view of a fuel cell manufacturing apparatus 10 which is an assembly according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the manufacturing apparatus 10. The manufacturing apparatus 10 includes electrodes 14a made of carbon paper on which catalysts are applied in advance on both surfaces of a solid polymer electrolyte membrane 12.
It is a device for joining 14b.

This manufacturing apparatus 10 has an electrode 14 at the substantially central portion.
Openings 16a and 16b corresponding to the dimensions of a and 14b are formed, and an enclosing portion 18 that encloses water for maintaining the solid polymer electrolyte membrane 12 in a predetermined wet state inside.
The first and second frame bodies 20a and 20b provided with the electrodes 14 and the first and second frame bodies 20a and 20b.
A fixing means 22 for integrally fixing the solid polymer electrolyte membrane 12 having a and 14b disposed on both sides in a sandwiched state.
And the electrodes 14a, from only the openings 16a, 16b
14b by heating and pressurizing the solid polymer electrolyte membrane 12
And a heating press means 24 for joining the electrodes 14a and 14b to both surfaces of the.

The solid polymer electrolyte membrane 12 is sandwiched between the first and second frames 20a and 20b, and the electrodes 14a and 1 are provided.
4b and first and second spacers 26a and 26b formed of PTFE (polytetrafluoroethylene) or the like,
Similarly, the first and second sheets 2 made of PTFE or the like
8a and 28b are laminated.

Positioning holes 30 are formed at the four corners of the solid polymer electrolyte membrane 12, and the first and second positioning holes 30 are formed.
The spacers 26a and 26b have electrodes 14a,
Openings 32a and 32b corresponding to the size of 14b are provided, while positioning holes 34a and 34b are formed at the four corners. Positioning holes 36a and 36b are formed at the four corners of the first and second sheets 28a and 28b, respectively.

The first frame body 20a, which is a lower frame, is made of stainless steel (SUS), and an O-ring (or square ring) 38 is formed around the opening 16a in the first frame body 20a. The O-ring 38 is provided and the enclosing portion 1 is provided.
The water channel 40 which comprises 8 is formed. Four positioning holes 42 are formed in the first frame 20a to a predetermined depth, and four screw holes 4 that constitute the fixing means 22 are formed.
4 are provided at the four corners of the first frame body 20a.

The second frame body 20b, which is the upper frame, is made of stainless steel (SUS), and the water inlet port 46 forming the enclosing portion 18 is provided on one side of the second frame body 20b. To be As shown in FIG. 2, the water introduction port 46 has a water passage 40 through an introduction passage 48 formed in the second frame 20b.
Open to the side. A water suction port 50 is provided on the other side portion of the second frame body 20b, and the water suction port 50 serves as the suction passage 5.
2 to the water channel 40 side.

The second frame 20b is provided with four positioning holes 54 having a predetermined depth and screw insertion holes 56 penetrating therethrough corresponding to the four corners of the second frame 20b. . One end of a stainless steel (SUS) positioning pin 58 is fitted into each hole 54, and the other end of the positioning pin 58 is connected to the hole 30 of the solid polymer electrolyte membrane 12.
Holes 34a of the first and second spacers 26a, 26b,
34b, the hole 3 of the first and second sheets 28a, 28b
6a, 36b and the hole 42 of the first frame 20a are integrally inserted to position them.

The fixing means 22 is provided with four screws 60, and each screw 60 is inserted into the hole portion 56 of the second frame body 20b and the tip side thereof is screwed into the screw hole 44 of the first frame body 20a. By doing so, the first and second frame bodies 20a, 20b
Are fixed integrally.

The heating press means 24 comprises a lower mold 62 and an upper mold 6.
4 and. A cooling unit 68 for supplying cooling water is provided on a base 66 that constitutes the lower mold 62. The cooling unit 68 has a passage 70 formed in a circle in the base 66, and the passage 70 has a cooling water inlet 72 and a cooling water outlet 7.
Communicate with 4.

A press portion 76 is provided on the base portion 66. On each side of the press portion 76, a tapered surface 78 that is inclined inward toward the base portion 66 side is formed, and
Inside the press section 76, a plurality of rod heaters 80
And a control thermocouple 82.

The upper mold 64 has the same structure as that of the lower mold 62. The same components are designated by the same reference numerals and detailed description thereof will be omitted.

Regarding the operation of the manufacturing apparatus 10 configured as described above, in connection with the manufacturing method according to the present embodiment, FIG.
The procedure will be described below.

First, after water repellent treatment is applied to carbon paper (step A), a catalyst is applied to the carbon paper to prepare electrodes 14a and 14b (steps B and C). On the other hand, the solid polymer electrolyte membrane 12 that has been sufficiently humidified in step D is replaced by the electrodes 14a, 14
b, the first and second spacers 26a and 26b, the first and second sheets 28a and 28b, and the first and second spacers.
It is assembled between the frame bodies 20a and 20b (step E).

That is, the electrodes 14a, 14b, the first and second spacers 26 are sandwiched with the solid polymer electrolyte membrane 12 interposed therebetween.
a, 26b, and the first and second sheets 28a, 28b are laminated. Further, the positioning pin 58 is provided with the hole 30, the first and second spacers 26 of the solid polymer electrolyte membrane 12.
The positioning pins 58 are inserted into the holes 34a, 34b of the a, 26b and the holes 36a, 36b of the first and second sheets 28a, 28b to position them, and the positioning pin 58 is used to position the first and second frames. Holes 42 of the bodies 20a, 20b,
Fit 54.

Therefore, each screw 6 which constitutes the fixing means 22.
0 is inserted into the hole portion 56 of the second frame body 20b and the tip side thereof is screwed into the screw hole 44 of the first frame body 20a, whereby the first and second frame bodies 20a and 20b are integrated. (See FIG. 4).

Next, the water suction port 50 provided in the second frame 20b communicates with the negative pressure side, and water is sucked from an external tank or the like through the water introduction port 46. This water is the water inlet 4
6 is supplied to the water passage 40 side through the introduction passage 48, and the water suction port 5 is provided through the suction passage 52 communicating with the water passage 40.
It is supplied to the 0 side. Then, the first and second frame bodies 20
When water is filled in the sealed portion 18 in each of a and 20b, the suction action of water by the negative pressure is stopped and the water inlet port 46
And the water suction port 50 is sealed (step F).

As shown in FIG. 2, the press parts 76 of the lower mold 62 and the upper mold 64 constituting the heating press means 24 are heated to about 160 ° C. via the rod heater 80 (step G). After the first and second frame bodies 20a and 20b are placed on the lower mold 62, the upper mold 64 moves in the direction of approaching the lower mold 62. Therefore, each press part 76 is inserted into the openings 16a and 16b of the first and second frames 20a and 20b, and the electrodes 14a and 14b and the solid polymer electrolyte membrane 12 are attached to the first and second sheets 28.
It is sandwiched with a predetermined pressure by interposing a and 28b.

At this time, each press part 76 is provided with an opening 16
Since the electrodes 14a and 14b are pressurized only from a and 16b, the applied pressure is not dispersed on the first and second frame bodies 20a and 20b side. Thereby, the electrodes 14a, 14b
A desired pressing force can be surely applied to, and the hot pressing process is efficiently performed (step H).

After the hot pressing time has elapsed for a predetermined time, the driving of the rod heater 80 is stopped and the cooling water is supplied to the cooling section 68. Specifically, cooling water having a predetermined temperature (for example, about 5 ° C.) is supplied to the passage 70 from the cooling water inlet 72, and this cooling water is pressed by the press section 76.
Etc. are cooled and discharged from the cooling water outlet 74 to the outside.
Therefore, the hot press means 24 is rapidly cooled by the cooling water while maintaining a predetermined pressurization state (step I).

When the hot press means 24 is cooled to a predetermined temperature (for example, about 50 ° C.), the pressure applied by the hot press means 24 is released (step J). Then, the lower mold 62 and the upper mold 64 are relatively moved in a direction in which they are separated from each other, and the screw 60 constituting the fixing means 22 is removed. As a result, the first frame body 20a and the second frame body 20b are separated from each other, and the electrodes 1 are formed on both surfaces of the solid polymer electrolyte membrane 12.
A fuel cell structure in which 4a and 14b are joined is obtained (step K).

In this case, in this embodiment, the electrodes 1 are formed on both sides.
4a, 14b are provided to dispose the first and second frame bodies 20a, 2
The solid polymer electrolyte membrane 12 sandwiched between 0b is the first
The water is sealed in the sealing portion 18 of the second frame 20a, 20b to maintain a predetermined wet state. Therefore,
When the electrodes 14a, 14b and the solid polymer electrolyte membrane 12 are heated and pressed through the heat press means 24, the water content in the solid polymer electrolyte membrane 12 is changed by the first and second frames 2.
The effect of preventing evaporation to the outside of 0a and 20b is obtained.

Moreover, the first and second frame bodies 20a, 20
Since water is enclosed inside b, the solid polymer electrolyte membrane 1
The moisture in 2 does not escape to the inside of the first and second frame bodies 20a and 20b, especially to the dead space. As a result, the solid polymer electrolyte membrane 12 can always be reliably maintained in a desired humidified state.

Further, after the electrodes 14a and 14b are bonded to both surfaces of the solid polymer electrolyte membrane 12 via the heating and pressing means 24, the heating and pressing means 24 is constructed before releasing the pressing force of the heating and pressing means 24. Cooling water is supplied to the cooling unit 68 to rapidly cool the hot press means 24. Therefore, it becomes possible to effectively prevent a defect such as damage of the solid polymer electrolyte membrane 12 due to the pressure of water vapor, as when the pressure is released in the hot press means 24 at a high temperature. .

Furthermore, in the present embodiment, the press parts 76 of the lower mold 62 and the upper mold 64 constituting the heating press means 24 are tapered surfaces that incline inward in the direction away from the electrodes 14a and 14b. Has 78. As a result, as shown in FIG. 2, the first and second frame bodies 20a,
A space S is provided between the inner wall forming the openings 16a, 16b of the 20b and each press part 76, and the heat of the press part 76 is applied to the first and second frame bodies 20a, 20b during hot press processing. It is possible to prevent running away.

Moreover, since the first and second sheets 28a and 28b are interposed between the solid polymer electrolyte membrane 12 and the first and second frames 20a and 20b, the first and second frames 20a are formed. , 20b to the solid polymer electrolyte membrane 12
It is possible to prevent metal ions from entering inside.

Although the fuel cell is used as the assembly in the present embodiment, the assembly is not limited to this. For example, an electrolytic treatment device of salt water, an ozone generation device, or the like may be used. The same effect can be obtained.

[0039]

As described above, in the method and apparatus for manufacturing an assembly having electrodes on both sides of the solid polymer electrolyte membrane according to the present invention, the solid polymer electrolyte membrane having electrodes on both sides is It is sandwiched between the first and second frames, and the first
And the solid polymer electrolyte membrane is maintained in a predetermined wet state by the water enclosed in the second frame. Therefore, the water in the solid polymer electrolyte membrane is evaporated to the outside of the first and second frames during the hot press treatment,
And it can be prevented from escaping inside the second frame,
The solid polymer electrolyte membrane can always be reliably maintained in a desired wet state.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of the manufacturing apparatus.

FIG. 3 is a process drawing showing the procedure of the manufacturing method according to the embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view of the manufacturing apparatus during operation.

FIG. 5 is an explanatory diagram of a manufacturing method according to a conventional technique.

[Explanation of symbols]

10 ... Manufacturing apparatus 12 ... Solid polymer electrolyte membranes 14a, 14b ... Electrodes 16a, 16b ...
Opening 18 ... Encapsulation 20a, 20b ...
Frame 22 ... Fixing means 24 ... Heating press means 26a, 26b ... Spacers 28a, 28b ...
Sheet 40 ... Water channel 46 ... Water introduction port 48 ... Introduction passage 50 ... Water suction port 58 ... Positioning pin 60 ... Screw 62 ... Lower mold 64 ... Upper mold 66 ... Base part 68 ... Cooling part 70 ... Passage 76 ... Press part 78 … Tapered surface 80… Rod heater

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takafumi Okamoto 1-4-1 Chuo, Wako-shi, Saitama Honda R & D Co., Ltd. (56) Reference JP-A-3-295171 (JP, A) JP-A-3 -84866 (JP, A) JP 5-109418 (JP, A) JP 6-203850 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 8/02 H01M 8/10 C25B 11/20

Claims (8)

(57) [Claims] 1. A method of manufacturing an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane , wherein the size of the electrode has a smaller area than the solid polymer electrolyte membrane at a substantially central portion. The first and second frames are sandwiched by the first and second frames having the openings corresponding to, and the first and second frames are integrally formed. A step of fixing, a step of enclosing water inside the first and second frames to maintain the solid polymer electrolyte membrane in a predetermined wet state, and inserting a press portion into each of the openings, Inserted
Both sides of the solid polymer electrolyte membrane by heating and pressurizing the both electrodes only from the both openings through the press section to bond the electrodes to both sides of the solid polymer electrolyte membrane. A method of manufacturing an assembly in which an electrode is arranged on a substrate. 2. The manufacturing method according to claim 1, wherein after the electrodes are bonded to both surfaces of the solid polymer electrolyte membrane, the heating press die is forcibly cooled before the pressure applied to the heating press die is released. A method for producing an assembly, in which electrodes are arranged on both surfaces of a solid polymer electrolyte membrane. 3. The method for producing a solid polymer electrolyte membrane according to claim 1, wherein the assembly is a fuel cell in which the electrodes are bonded to both surfaces of the solid polymer electrolyte membrane. A method of manufacturing an assembly in which electrodes are arranged on both sides. 4. An apparatus for manufacturing an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane , wherein the size of the electrode has a smaller area than the solid polymer electrolyte membrane at substantially the central portion. An opening corresponding to is formed,
First and second frame bodies provided with an enclosing portion for enclosing water for maintaining the solid polymer electrolyte membrane in a predetermined wet state, and the electrodes for the first and second frame bodies. Fixing means for integrally fixing the solid polymer electrolyte membrane disposed on both sides in a sandwiched state, and pressing parts respectively inserted into both the opening parts were inserted.
A solid polymer electrolyte membrane, comprising: a heating and pressing unit that heats and pressurizes the both electrodes only from the both openings through the pressing unit to bond the electrodes to both surfaces of the solid polymer electrolyte membrane. A manufacturing device for an assembly in which electrodes are provided on both surfaces of the assembly. 5. The solid polymer electrolyte membrane according to claim 4, wherein the hot pressing means is provided with a cooling section for supplying a cooling medium for cooling the hot pressing means itself. Assembly manufacturing equipment with electrodes on both sides. 6. An apparatus for manufacturing an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane, wherein an opening corresponding to the size of the electrode is formed at a substantially central portion, and the solid is provided inside. First and second frame bodies provided with an enclosure for enclosing water for maintaining the polymer electrolyte membrane in a predetermined wet state, and the first and second frame bodies, wherein the electrodes are provided on both surfaces. Fixing means for integrally fixing the solid polymer electrolyte membrane in a sandwiched state, and heating and pressing the both electrodes only from the opening to bond the electrodes to both surfaces of the solid polymer electrolyte membrane and a heat press means, said heated press means, a side of the flop <br/> less portion inserted into the opening, a tapered surface inclined inwardly in a direction away from the electrode Of the solid polymer electrolyte membrane characterized by being provided The assembly of the manufacturing apparatus which is disposed an electrode on the surface. 7. The manufacturing apparatus according to any one of claims 4 to 6, wherein the assembly is a fuel cell in which the electrodes are bonded to both surfaces of the solid polymer electrolyte membrane. An apparatus for manufacturing an assembly in which electrodes are arranged on both sides of a solid polymer electrolyte membrane. 8. The manufacturing method according to claim 1, wherein the substantially central portion has an area smaller than that of the solid polymer electrolyte membrane.
In the first and second frame in which an opening is formed that corresponds to the dimensions of have the electrode, with sandwiching the solid polymer electrolyte membrane on which the electrode is disposed on both sides, the first and second frame The step of integrally fixing the body is performed by the first and second frame bodies in which an opening corresponding to the size of the electrode having a smaller area than the solid polymer electrolyte membrane is formed in the substantially central portion. , A first and a second system made of PTEF on both sides of the solid polymer electrolyte membrane having the electrodes on both sides.
The step of sandwiching the laminated body in which the sheets are laminated and fixing the first and second frame bodies integrally is performed, and the press portions are inserted into the both opening portions, respectively.
The step of joining the electrodes to both surfaces of the solid polymer electrolyte membrane by heating and pressurizing the both electrodes only from the both openings through the pressing section, inserting the pressing sections into the both openings, respectively, and inserting the electrodes. Was
Characterized by replacing the step of bonding the electrode to the two electrodes only from the both the openings through the press section on both sides of the first and second said heating and pressurizing through a sheet polymer electrolyte membrane And a method for manufacturing an assembly in which electrodes are provided on both surfaces of a solid polymer electrolyte membrane.