JPH1040932A - Method and device for manufacturing assembly with electrodes arranged on both surfaces of solid high polymer electrolyte film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively check evaporation of moisture from a solid high poly mer electrolyte film, and reliably join electrodes to both surfaces of this solid high polymer electrolyte film. SOLUTION: A manufacturing method and a device are provided with first and second frame bodies 20a and 20b in which opening parts 16a and 16b corresponding to electrodes 14a and 14b are formed in an almost central part and inside which a sealing part 18 is arranged to seal water to maintain a solid high polymer electrolyte film 12 in a prescribed wetting condition, a fixing means 22 to integrally fix these first and second frame bodies 20a and 20b and a heating press means 24 to join the electrodes 14a and 14b to both surfaces of the solid high polymer electrolyte film 12 by heating and pressurizing the electrodes 14a and 14b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Usually, an assembly having electrodes disposed on both sides of a solid polymer electrolyte membrane is used for a fuel cell, a salt water electrolysis apparatus,
Alternatively, it is used for an ozone generation device or the like. For example, fuel cells have been developed in which a plurality of fuel cell structures each having an anode electrode and a cathode electrode opposed to each other with a solid polymer electrolyte membrane interposed therebetween are sandwiched by separators and stacked. It is being put to practical use.

In this type of fuel cell, for example, hydrogen gas (fuel gas) generated by steam reforming of methanol is supplied to an anode electrode and oxidizing gas (air) is supplied to a cathode electrode. Thus, the hydrogen gas is ionized and flows through the solid polymer electrolyte membrane, whereby electric energy is obtained outside.

[0004] In the above-mentioned fuel cell, an operation is performed in which the solid polymer electrolyte membrane is sandwiched between two catalyst electrodes (gas diffusion electrodes) and integrated by hot pressing. However, it has been pointed out that when hot pressing is performed at a temperature of 100 ° C. or more, moisture in the solid polymer electrolyte membrane tends to evaporate, and the solid polymer electrolyte membrane is thereby deteriorated.

Therefore, a manufacturing method disclosed in Japanese Patent Application Laid-Open No. 3-295171 is adopted. In this manufacturing method, as shown in FIG. 5, spacers 5a and 5b in which openings 3a and 3b corresponding to catalyst electrodes 4a and 4b provided 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.
Is bonded to both surfaces of the solid polymer electrolyte membrane 2, the evaporation of moisture from the solid polymer electrolyte membrane 2
a, 5b.

[0006]

However, in the above-mentioned conventional method, the pressing force by the press dies 8a and 8b is dispersed to the spacers 5a and 5b in addition to the catalyst electrodes 4a and 4b. As a result, the pressing force applied to the catalyst electrodes 4a, 4b decreases, and there is a problem that poor fusion between the catalyst electrodes 4a, 4b and the solid polymer electrolyte membrane 2 is caused. At that time, a device is devised to lengthen the pressurizing time to avoid a fusion defect between the catalyst electrodes 4a and 4b and the solid polymer electrolyte membrane 2. However, this makes the cycle time longer, It has been pointed out that the evaporation of water from the solid polymer electrolyte membrane 2 is caused, and the quality is reduced.

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

[0008]

In order to solve the above-mentioned problems, the present invention provides a solid polymer electrolyte membrane having electrodes disposed on both sides thereof, which is sandwiched between first and second frames. Water is sealed inside the first and second frames, and the solid polymer electrolyte membrane is maintained in a predetermined wet state. Next, heat and pressure are applied only from the openings formed in the first and second frames, and electrodes are bonded to both surfaces of the solid polymer electrolyte membrane.

As described above, the solid polymer electrolyte membrane and the electrode are sandwiched between the first and second frames, and water is sealed inside the first and second frames. For this reason,
It is possible to prevent the water in the solid polymer electrolyte membrane from evaporating to the outside of the first and second frames during the heat treatment, and the water in the solid polymer electrolyte membrane is prevented from evaporating from the first and second frames. 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 performed on the electrode only from the opening, the pressing force is not dispersed except for the electrode, and the desired pressing force is reliably applied to the electrode. be able to.

After the electrodes are joined to both surfaces of the solid polymer electrolyte membrane, the heating press mold is forcibly cooled before the pressing force of the heating press mold is released. Therefore, the pressing force is not released when the heating press die is in a high temperature state, and it is possible to effectively prevent problems such as breakage of the solid polymer electrolyte membrane due to the pressure of steam.

Further, the heating press means has a tapered surface which is inclined inward in a direction away from the electrode on a side of the press portion inserted into the opening. Thereby, a space is provided between the first and second frames and the side of the press section, and the heat of the press section transfers the heat of the first and second frames.
Escape to the frame side can be prevented.

[0013]

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

The manufacturing apparatus 10 has an electrode 14 at a substantially central portion.
The opening portions 16a and 16b corresponding to the dimensions of a and 14b are formed, and an enclosing portion 18 for enclosing water therein for maintaining the solid polymer electrolyte membrane 12 in a predetermined wet state.
The first and second frames 20a and 20b provided with the electrodes 14 and the first and second frames 20a and 20b are
a, a fixing means 22 for integrally fixing the solid polymer electrolyte membrane 12 sandwiched between the solid polymer electrolyte membranes 12 disposed on both sides thereof;
And the electrodes 14a, only through the openings 16a, 16b.
14b is heated and pressurized to form the solid polymer electrolyte membrane 12
And heating press means 24 for joining the electrodes 14a and 14b to both surfaces of the electrode.

The electrodes 14a, 1b are sandwiched between the first and second frames 20a, 20b with the solid polymer electrolyte membrane 12 interposed therebetween.
4b, first and second spacers 26a, 26b formed of PTFE (polytetrafluoroethylene) or the like;
First and second sheets 2 similarly formed of PTFE or the like
8a and 28b are laminated.

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

The first frame 20a, which is the lower frame, is made of stainless steel (SUS). The first frame 20a is provided with an O-ring (or square ring) 38 around the opening 16a. The O-ring 38 is provided to
A water channel 40 constituting 8 is formed. In the first frame 20a, four positioning holes 42 are formed to a predetermined depth, and four screw holes 4 forming the fixing means 22 are formed.
4 are provided at four corners of the first frame 20a.

The second frame 20b, which is the upper frame, is made of stainless steel (SUS). On one side of the second frame 20b, a water inlet 46 forming the enclosing portion 18 is provided. Can be As shown in FIG. 2, the water introduction port 46 is connected to the water passage 40 through an introduction passage 48 formed in the second frame 20b.
Opened to the side. A water suction port 50 is provided on the other side of the second frame 20b.
It is opened to the water channel 40 side via 2.

The second frame 20b is provided with four positioning holes 54 having a predetermined depth and screw insertion holes 56 penetrating corresponding to the four corners of the second frame 20b. . One end of a positioning pin 58 made of stainless steel (SUS) 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, holes 3 in the first and second sheets 28a, 28b
6a, 36b and the holes 42 of the first frame 20a are integrally inserted and positioned.

The fixing means 22 has four screws 60, each of which is inserted into the hole 56 of the second frame 20b and the leading end of which is screwed into the screw hole 44 of the first frame 20a. By doing so, the first and second frames 20a, 20b
Are fixed integrally.

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

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

The upper die 64 has the same configuration as the lower die 62, and the same components are denoted by the same reference characters and will not be described in detail.

The operation of the manufacturing apparatus 10 configured as described above will be described with reference to FIG.
This will be described below according to the procedure shown in FIG.

First, after the carbon paper is subjected to a water-repellent treatment (step A), a catalyst is applied to the carbon paper to form electrodes 14a and 14b (steps B and C). On the other hand, the solid polymer electrolyte membrane 12 sufficiently humidified in Step D is
b, the first and second spacers 26a and 26b, and the first and second sheets 28a and 28b integrally with the first and second spacers 26a and 26b.
It is assembled between the frames 20a and 20b (step E).

That is, the electrodes 14a, 14b, the first and second spacers 26 are sandwiched by the solid polymer electrolyte membrane 12 therebetween.
a, 26b and the first and second sheets 28a, 28b are stacked. Further, the positioning pins 58 are connected to the holes 30 of the polymer electrolyte membrane 12, the first and second spacers 26.
The positioning pins 58 are inserted into the holes 34a and 34b of the first and second sheets 28a and 28b and are positioned integrally with the holes 34a and 34b of the first and second sheets 28a and 28b. Holes 42 of the bodies 20a, 20b,
54 is fitted.

Therefore, each screw 6 constituting the fixing means 22
0 is inserted into the hole 56 of the second frame 20b and its leading end is screwed into the screw hole 44 of the first frame 20a, whereby the first and second frames 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 via the water introduction port 46. This water is supplied to the water inlet 4
6 is supplied to the water channel 40 side through the introduction channel 48 and is connected to the water suction port 5 through the suction channel 52 communicating with the water channel 40.
It is supplied to the 0 side. Then, the first and second frames 20
When the water is filled in the sealing portion 18 in the a and 20b, the suction operation of the water by the negative pressure is stopped, and
And the water suction port 50 is sealed (step F).

As shown in FIG. 2, each press section 76 of the lower mold 62 and the upper mold 64 constituting the heating press means 24 is heated to about 160 ° C. via the rod heater 80 (step G). After the first and second frames 20a and 20b are placed on the lower mold 62, the upper mold 64 moves in a direction approaching the lower mold 62. For this reason, each press section 76 is inserted into the openings 16a, 16b of the first and second frames 20a, 20b, and the electrodes 14a, 14b and the solid polymer electrolyte membrane 12 are connected to the first and second sheets 28.
a and 28b are interposed therebetween at a predetermined pressure.

At this time, each press section 76 is
Since the electrodes 14a and 14b are pressurized only from the electrodes a and 16b, the pressing force is not dispersed to the first and second frame bodies 20a and 20b. Thereby, the electrodes 14a, 14b
Can be reliably applied with a desired pressing force, and the hot pressing process is efficiently performed (step H).

After the elapse of a predetermined time, the driving of the rod heater 80 is stopped, and cooling water is supplied to the cooling section 68. Specifically, cooling water at a predetermined temperature (for example, about 5 ° C.) is supplied to the passage 70 from the cooling water inlet 72, and the cooling water is
The cooling water is discharged to the outside through the cooling water outlet 74.
Therefore, the heating press means 24 is rapidly cooled by the cooling water while maintaining the predetermined pressurized state (step I).

When the heating press 24 is cooled to a predetermined temperature (for example, about 50 ° C.), the pressure applied by the heating press 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 20a and the second frame 20b are separated from each other, and the electrodes 1 are placed 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 provided on both surfaces.
4a and 14b, and the first and second frames 20a and 20a,
0b, the solid polymer electrolyte membrane 12 is
The water is sealed in the sealing portion 18 of each of the second frames 20a and 20b, and is maintained in a predetermined wet state. Therefore,
When the electrodes 14a and 14b and the solid polymer electrolyte membrane 12 are heated and pressurized through the heating press means 24, the moisture in the solid polymer electrolyte membrane 12 is reduced by the first and second frame members 2.
The effect that evaporation to the outside of 0a and 20b can be prevented can be obtained.

Moreover, the first and second frames 20a, 20
b, water is sealed inside the solid polymer electrolyte membrane 1
2 does not escape to the interior of the first and second frames 20a, 20b, especially to the dead space. Thereby, the solid polymer electrolyte membrane 12 can always be reliably maintained in a desired humidified state.

Further, after the electrodes 14a and 14b are joined to both surfaces of the solid polymer electrolyte membrane 12 via the heating press means 24, the heating press means 24 is constituted before the pressing force of the heating press means 24 is released. Cooling water is supplied to the cooling section 68 to be heated, and the heating press means 24 is rapidly cooled. Therefore, it is possible to effectively prevent problems such as breakage of the solid polymer electrolyte membrane 12 due to the pressure of steam, such as when the pressing force is released while the heating press means 24 is at a high temperature. .

Further, in the present embodiment, each press portion 76 of the lower mold 62 and the upper mold 64 constituting the heating press means 24 has a tapered surface inclined inward in a direction away from the electrodes 14a, 14b. 78. Thereby, as shown in FIG. 2, the first and second frames 20a,
A space S is provided between the inner walls constituting the openings 16a, 16b of the 20b and each of the press sections 76, and the heat of the press section 76 generates heat during the hot press process on the first and second frame bodies 20a, 20b side. Can be prevented from escaping.

Further, 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 , 20b to the solid polymer electrolyte membrane 12
It is possible to prevent metal ions from entering the inside.

Although the present embodiment has been described using a fuel cell as an assembly, the present invention is not limited to this. For example, even if an electrolytic treatment device for salt water, an ozone generation device, or the like is used, Similar effects can be obtained.

[0039]

As described above, in the method and apparatus for manufacturing an assembly in which electrodes are provided on both sides of a solid polymer electrolyte membrane according to the present invention, the solid polymer electrolyte membrane in which electrodes are provided on both sides is used. The first and second frames are sandwiched between the first and second frames.
Further, the solid polymer electrolyte membrane is maintained in a predetermined wet state by the water sealed in the second frame. For this reason, the moisture in the solid polymer electrolyte membrane evaporates to the outside of the first and second frames during the hot pressing,
And can be prevented from escaping into the second frame,
The solid polymer electrolyte membrane can always be reliably maintained in a desired wet state.

[Brief description of the drawings]

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

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

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

FIG. 4 is a longitudinal 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]

DESCRIPTION OF SYMBOLS 10 ... Manufacturing apparatus 12 ... Solid polymer electrolyte membrane 14a, 14b ... Electrode 16a, 16b ...
Opening 18: Enclosure 20a, 20b ...
Frame 22 ... Fixing means 24 ... Heat pressing means 26a, 26b ... Spacers 28a, 28b ...
Sheet 40: Water channel 46: Water inlet 48 ... Introductory passage 50: Water suction port 58 ... Positioning pin 60 ... Screw 62 ... Lower die 64 ... Upper die 66 ... Base part 68 ... Cooling part 70 ... Passage 76 ... Press part 78 ... tapered surface 80 ... rod heater

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takafumi Okamoto 1-4-1 Chuo, Wako-shi, Saitama

Claims (7)

[Claims] 1. A method for manufacturing an assembly having electrodes disposed on both surfaces of a solid polymer electrolyte membrane, wherein a first and a second frame having an opening corresponding to the dimensions of the electrode at a substantially central portion. The electrode sandwiches the solid polymer electrolyte membrane disposed on both sides thereof, and
And a step of integrally fixing the second frame, a step of sealing water inside the first and second frames to maintain the solid polymer electrolyte membrane in a predetermined wet state, and the opening Bonding the electrodes to both surfaces of the solid polymer electrolyte membrane by heating and pressurizing the electrodes only from the following, and an assembly provided with electrodes on both surfaces of the solid polymer electrolyte membrane, characterized by comprising: Production method. 2. The method according to claim 1, wherein after the electrodes are joined to both surfaces of the solid polymer electrolyte membrane, the heating press mold is forcibly cooled before the pressing force of the heating press mold is released. A method for producing an assembly, wherein electrodes are provided on both surfaces of a solid polymer electrolyte membrane. 3. The method according to claim 1, wherein the assembly is a fuel cell in which the electrodes are joined to both surfaces of the solid polymer electrolyte membrane. A method of manufacturing an assembly having electrodes disposed on both sides. 4. An apparatus for manufacturing an assembly, wherein electrodes are provided on both surfaces 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 body is formed inside the opening. First and second frames provided with an enclosing portion for enclosing water for maintaining the polymer electrolyte membrane in a predetermined wet state; and the first and second frames are provided on both sides of the electrodes. Fixing means for integrally fixing the solid polymer electrolyte membrane sandwiched therebetween, and heating for heating and pressing the electrode only from the opening to join the electrode to both surfaces of the solid polymer electrolyte membrane An apparatus for manufacturing an assembly, wherein electrodes are provided on both surfaces of a solid polymer electrolyte membrane, comprising: pressing means. 5. The manufacturing apparatus according to claim 4, wherein said heating press means includes a cooling section for supplying a cooling medium for cooling said heating press means itself. An assembly manufacturing device with electrodes arranged on both sides. 6. The manufacturing apparatus according to claim 4, wherein said heating press means is inclined inward in a direction away from said electrode at a side of a press section inserted into said opening. An apparatus for manufacturing an assembly in which electrodes are provided on both surfaces of a solid polymer electrolyte membrane, wherein a tapered surface is provided. 7. The manufacturing apparatus according to claim 4, wherein the assembly is a fuel cell in which the electrodes are bonded to both surfaces of the solid polymer electrolyte membrane. An assembly manufacturing apparatus in which electrodes are arranged on both surfaces of a solid polymer electrolyte membrane.