KR20170049662A - Membrane-electrode assembly and preparation method thereof - Google Patents

Abstract

The present invention relates to a membrane-electrode assembly used in a fuel cell or the like and a preparation method thereof. As a first gasket and a second gasket are respectively stacked on the upper surface and the lower surface of an edge portion of a membrane in which electrodes are not stacked, the outside end of the first and second gaskets are bonded to each other and seal the edge portion of the membrane. Also, as a third gasket and a fourth gasket are stacked on the upper surface and the lower surface of a bonding portion, alignment degradation between components due to height step according to formation of the bonding unit is prevented so reliability can be improved.

Description

[0001] MEMBRANE ELECTRODE ASSEMBLY AND PREPARATION METHOD THEREOF [0002]

The present invention relates to a membrane-electrode assembly (MEA) used in a fuel cell or the like and a method for manufacturing the same.

BACKGROUND ART A fuel cell is a cell that converts the chemical reaction energy of a fuel and an oxidant into electrical energy. Hydrocarbons such as methanol, butane and the like are used as the fuel, and oxygen is used as the oxidant. Particularly, such a fuel cell is attracting attention due to its advantages such as high efficiency and abundance of fuel to be used without emitting pollutants such as NOx and SOx.

The most basic unit for generating electricity in a fuel cell is a membrane-electrode assembly (MEA), which is composed of a membrane used as an electrolyte membrane and an anode and a cathode formed on both sides of the membrane. In the anode electrode, the oxidation reaction of the fuel occurs, hydrogen ions and electrons are generated, hydrogen ions move to the cathode electrode through the membrane, and oxygen (oxidant) and the membrane The electrons are transferred to the external circuit by the reaction that the electrons and the hydrogen ions transferred through the reaction are generated.

The membranes used in membrane-electrode assemblies of such fuel cells have properties of hygroscopicity, expansion and wrinkling, and the like. This is not only difficult to join in the manufacturing process of the fuel cell stack, .

In order to solve this problem, as shown in FIG. 4, a membrane-electrode assembly in the form of gaskets 310 and 320 has been manufactured to improve the moisture resistance and durability of the membrane at both ends of the membrane. The gaskets 310 and 320 can increase the mechanical strength of the membrane-electrode assembly to facilitate stacking, improve durability during operation of the stack, and stabilize gas leakage.

However, in the conventional MEA structure, since the side of the membrane 100 is exposed to the outside at the edge portion (the dashed line portion in FIG. 4) of the MEA, the water inside the membrane can be drained to the outside, The moisture can be admitted into the MEA. Accordingly, when the fuel cell is driven for a long time, the performance of the fuel cell may be deteriorated due to water flow through the edge portion of the MEA, or excessive water may be generated.

In order to solve this problem, when the edge portion of the MEA is sealed by using an additional gasket, there occurs a step of thickness (height) according to such sealing. In the case of stacking a plurality of MEAs There is a problem that the alignment between the components deteriorates and the reliability of the fuel cell can not be satisfied.

Korean Patent Publication No. 2010-0018579 (Feb.

Accordingly, an object of the present invention is to provide a membrane-electrode structure having a novel structure capable of preventing the deterioration of the performance and reliability of the fuel cell by improving the alignment between the constituent components while solving the problem that the edge portion of the conventional membrane- And a method for producing the same.

In accordance with the above object, the present invention provides a method of manufacturing a membrane, comprising: (a) a membrane; (b) a first gasket which is laminated on the upper and lower surfaces of the membrane so as to cover the rim of the membrane while the outer ends thereof protrude, the outer ends being joined to each other to seal the side edge of the membrane, 2 gasket; (c) two electrodes stacked on the upper and lower surfaces of the membrane, respectively, so as to cover a central portion of the membrane where the first gasket and the second gasket are not present; And (d) a third gasket and a fourth gasket which are respectively laminated on the upper and lower surfaces of the joint, respectively.

According to another aspect of the present invention, there is provided a method of manufacturing a membrane, comprising: (1) preparing a membrane; (2) stacking a first gasket and a second gasket on the upper and lower surfaces of the membrane, respectively, so that the outer end of the membrane covers the edge of the membrane; (3) sealing the side edges of the membrane while joining the outer ends of the first gasket and the second gasket together to form a joint; (4) stacking two electrodes on the upper and lower surfaces of the membrane, respectively, so as to cover a central portion of the membrane where the first gasket and the second gasket are not present; And (5) laminating a third gasket and a fourth gasket on the upper and lower surfaces of the joint, respectively.

The present invention also provides a fuel cell comprising the membrane-electrode assembly.

The membrane-electrode assembly (MEA) of the present invention protects the upper and lower surfaces of the membrane edge portions where the electrodes are not laminated by the first gasket and the second gasket, respectively, and the outer ends thereof are joined to form a joint portion. It is possible to completely block the water flow through the edge portion of the MEA.

In addition, since the third gasket and the fourth gasket are laminated on the upper and lower surfaces of the junction, the membrane-electrode assembly of the present invention can prevent the lowering of the alignment between the components due to the height difference due to the formation of the junction, have.

In addition, the membrane-electrode assembly of the present invention is manufactured through a simpler process than the conventional method, and can solve the height difference while sealing the edge portion of the MEA, which is advantageous for application to the fuel cell field.

1 shows an example of a cross-sectional structure of a membrane-electrode assembly of the present invention.
2 is an enlarged view of the edge portion in the example of the cross-sectional structure of the membrane-electrode assembly of the present invention.
3 shows another example of the cross-sectional structure of the membrane-electrode assembly of the present invention.
4 shows a cross-sectional structure of a conventional membrane-electrode assembly.
5 to 8 show various examples of the method for producing the membrane-electrode assembly of the present invention.

Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings. In the accompanying drawings, sizes, intervals, and the like may be exaggerated to facilitate understanding, and descriptions of those apparent to those skilled in the art may be omitted.

Referring to Figure 1, the membrane-electrode assembly of the present invention comprises

(a) a membrane 100;

(b) are laminated on the upper and lower surfaces of the membrane 100 such that the outer ends thereof protrude while covering the edge of the membrane 100, and the outer ends of the membrane 100 are joined to each other, A first gasket 310 and a second gasket 320 sealing the edge;

(c) two electrodes 210 and 210 stacked on the upper and lower surfaces of the membrane 100 so as to cover the central portion of the membrane 100 where the first gasket 310 and the second gasket 320 are not present, 220); And

(d) a third gasket 330 and a fourth gasket 340 stacked on the upper and lower surfaces of the joint, respectively.

Hereinafter, each component will be described in detail.

electrode

The membrane-electrode assembly has two electrodes 210 and 220 facing each other.

The two electrodes may be an anode electrode and a cathode electrode, respectively. The electrode may be a gas diffusion electrode.

The anode electrode can generate hydrogen ions by oxidizing hydrogen or a liquid hydrocarbon fuel such as methanol, butanol, propanol, formic acid and the like. The anode may comprise a catalyst layer and a gas diffusion layer. As the catalyst layer, a catalyst such as platinum, ruthenium, osmium, a platinum-ruthenium alloy, a platinum-osmium alloy, a platinum-palladium alloy, or a platinum-transition metal alloy may be used.

The cathode electrode serves to reduce an oxidizing agent such as oxygen. The cathode may comprise a catalyst layer and a gas diffusion layer. For example, platinum or a platinum-transition metal alloy may be used for the catalyst layer.

The gas diffusion layer included in the anode electrode and the cathode electrode functions as a current conductor and also moves and diffuses a reactant and water such as a fuel and an oxidant. The gas diffusion layer may be formed of, for example, carbon paper, carbon cloth, carbon felt, or the like. A microporous layer may be formed on a surface of the gas diffusion layer in contact with the catalyst layer.

The two electrodes 210 and 220 may have the same area.

In addition, the two electrodes 210 and 220 may cover a central portion of an area corresponding to 60 to 99% of the total area of the membrane 100. More specifically, the two electrodes 210 and 220 may cover a central portion of an area corresponding to 60 to 95%, 70 to 98%, or 70 to 95% of the total area of the membrane 100.

Membrane

The membrane 100 transfers hydrogen ions generated from the anode electrode of the membrane-electrode assembly to the cathode electrode and electrically separates the anode electrode and the cathode electrode.

The membrane is not particularly limited as long as it is a polymer film used as an electrolyte membrane in a fuel cell or the like. The membrane may be a flexible polymer film.

For example, the membrane may be made of a perfluorosulfonic acid polymer resin, a polyimide resin, a polyvinylidene fluoride resin, a polyether sulfone resin, a polyphenylene sulfide resin, a polyphenylene oxide resin, a polyphosphine resin, a polyethylene naphthalate A polymer resin selected from the group consisting of a resin, a polyester resin, a doped polybenzimidazole resin, a polyether ketone resin, a polysulfone resin, an ion conductive polymer resin thereof, and a mixed resin thereof.

The thickness of the membrane is not particularly limited, but may be, for example, 10 占 퐉 to 200 占 퐉, specifically 10 占 퐉 to 150 占 퐉, more specifically 20 占 퐉 to 100 占 퐉.

The first gasket and the second gasket

The first gasket 310 and the second gasket 320 cover the upper and lower surfaces of the edge of the membrane 100 to protect the edge of the membrane 100 and prevent the flow of water.

The first gasket 310 and the second gasket 320 are stacked on the upper and lower surfaces of the membrane 100 so as to protrude from the side edge of the membrane 100 while covering the edge of the membrane 100.

The two electrodes 210 and 220 are formed on the upper and lower surfaces of the membrane 100 so as to cover the center portion of the membrane 100 where the first gasket 310 and the second gasket 320 are not present. The two electrodes 210 and 220 may be stacked on the upper and lower surfaces of the membrane 100 such that the edges of the two electrodes overlap with the first gasket 310 and the second gasket 320 (See Fig. 1).

Alternatively, the two electrodes 210 and 220 may not be overlapped with the first gasket 310 and the second gasket 320. In this case, the edges of the two electrodes 210 and 220 It is preferable that the ends of the first gasket 310 and the second gasket 320 are in contact with each other so as to be free from the gap between the first gasket 310 and the second gasket 320.

The first gasket and the second gasket may have the same area.

The first gasket 310 and the second gasket 320 may cover an edge portion of an area corresponding to 1 to 40% of the total area of the membrane 100. More specifically, the first gasket 310 and the second gasket 320 correspond to 3 to 40%, 5 to 40%, 5 to 35%, or 5 to 30% of the total area of the membrane 100 It is possible to cover the edge portion of the area.

The first gasket and the second gasket may be formed of a polymer film. For example, the first gasket and the second gasket may include a polymer resin selected from the group consisting of a polyphenylene sulfide resin, a polyester resin, a polyethylene resin, a polypropylene resin, and a mixed resin thereof.

The first gasket and the second gasket may have a thickness of 10 탆 to 60 탆, and more specifically, may have a thickness of 10 탆 to 40 탆.

The first gasket 310 and the second gasket 320 seal the side edges of the membrane 100 with their outer ends joined together to form a joint.

The junction between the first gasket 310 and the second gasket 320 may be thermally fused so that no separate adhesive may be present between the first and second gaskets of the junction. Or the joint may be adhered by an adhesive so that an adhesive may be present between the first gasket and the second gasket of the joint.

As shown in FIG. 2, the first gasket 310 and the second gasket 320 may have a height difference dh between the surface of the portion stacked on the membrane 100 and the surface of the bonding portion.

The third gasket and the fourth gasket

The third gasket 330 and the fourth gasket 340 are stacked on the upper surface and the lower surface of the joining portion of the first gasket 310 and the second gasket 320, (Dh) generated due to the joining portion of the gasket (320).

That is, when the plurality of membrane-electrode assemblies are stacked to constitute the fuel cell, the height step (dh) may cause the alignment between the constituent components to deteriorate. Due to the third gasket and the fourth gasket, Can be solved.

Specifically, as shown in FIG. 2, the third gasket 330 is stacked such that its upper surface is located at the same height as the extension of the upper surface of the first gasket 310 stacked on the upper surface of the membrane 100, 4 gasket 340 may be stacked such that its lower surface is located at the same height as the extension of the lower surface of the second gasket 320 stacked on the lower surface of the membrane 100.

The third gasket 330 has a thickness corresponding to a height difference dh between the upper surface of the first gasket 310 and the upper surface of the bonding portion, which are stacked on the upper surface of the membrane 100, The gasket 340 may have a thickness corresponding to a height difference between the lower surface of the second gasket 320 laminated on the lower surface of the membrane 100 and the lower surface of the bonding portion.

The total thickness t1 of the first gasket 310 and the second gasket 320 on the membrane 100 and the total thickness t1 of the third gasket 330 and fourth The total thickness t2 of the portion where the gasket 340 is laminated on the joint portion may be equal to each other.

The third gasket and the fourth gasket may be formed of a polymer film.

The polymer film which can be used as the third gasket and the fourth gasket is not particularly limited as long as it is a polymer film which can be formed into a film having a thickness of tens to hundreds of micrometers (占 퐉).

In addition, the third gasket and the fourth gasket may include a laminate of two or more polymer films, for example, a laminate of two or five polymer films.

The polymer film may be a polymer resin selected from the group consisting of a polyphenylene sulfide resin, a polyester resin, a polyethylene resin, a polypropylene resin, a polyacrylonitrile resin, a polyvinyl chloride resin, an ethylene vinyl acetate resin, . ≪ / RTI >

The third gasket 330 and the fourth gasket 340 may be laminated on the upper and lower surfaces of the joint by an adhesive. Accordingly, an adhesive may be present between the third gasket 330 and the upper surface of the bonding portion. Also, an adhesive may be present between the fourth gasket 340 and the lower surface of the bonding portion.

The three gaskets 330 and the fourth gaskets 340 may be thermally welded and laminated on the upper and lower surfaces of the joints. Accordingly, a separate adhesive may not be present between the third gasket 330 and the fourth gasket 340 and the joint.

The fifth gasket and the sixth gasket

Referring to FIG. 3, the membrane-electrode assembly of the present invention includes a fifth gasket 350 stacked to cover the upper surface of the first gasket 310 and the upper surface of the third gasket 330; And a sixth gasket 360 stacked to cover the lower surface of the second gasket 320 and the lower surface of the fourth gasket 340.

The fifth gasket 350 and the sixth gasket 360 seal the side surfaces of the two electrodes 210 and 220 while eliminating steps due to height difference between the electrodes 210 and 220 and the membrane 100, Electrode assembly to reduce the gap between the layers when stacking a plurality of membrane-electrode assemblies to constitute a battery.

Specifically, the fifth gasket 350 is stacked to cover the upper surface of the portion of the first gasket 310 stacked on the membrane 100, and the upper surface of the third gasket 330. The sixth gasket 360 is stacked to cover both the lower surface of the portion of the second gasket 320 stacked on the membrane 100 and the lower surface of the fourth gasket 340.

The height difference dh caused by the joining of the outer ends of the first gasket 310 and the second gasket 320 may be greater than the height difference dh between the third gasket 330 and the fourth gasket 320, Even if the fifth gasket 350 and the sixth gasket 360 in the form of a film are laminated, the alignment between the constituent components is not lowered, and the reliability of the membrane-electrode assembly can be improved.

The fifth gasket and the sixth gasket may be formed of a polymer film.

For example, the fifth gasket and the sixth gasket may include a polymer resin selected from the group consisting of a polyphenylene sulfide resin, a polyester resin, a polyethylene resin, a polypropylene resin, and a mixed resin thereof.

Hereinafter, a method for producing the membrane-electrode assembly of the present invention will be described in detail.

5, a method of manufacturing a membrane-electrode assembly according to an example of the present invention includes:

(1) fabricating a membrane 100;

(2) stacking a first gasket 310 and a second gasket 320 on the upper and lower surfaces of the membrane 100 such that the outer edge of the membrane 100 protrudes while covering the edge of the membrane 100;

(3) sealing the side edges of the membrane 100 by joining the outer ends of the first gasket 310 and the second gasket 320 together to form a joint;

(4) Two electrodes 210 and 220 are formed on the upper and lower surfaces of the membrane 100 so as to cover the central portion of the membrane 100 where the first and second gaskets 310 and 320 are not present. Respectively; And

(5) stacking a third gasket 330 and a fourth gasket 340 on the upper and lower surfaces of the joint, respectively.

Each step will be described in detail below.

(1) Manufacture of membranes

Step (1) is the step of producing the membrane 100.

The membrane may be a flexible polymer film, and specific types of the polymer resin used as the material thereof are as exemplified above.

Preferably, the membrane can be made by hydroperoxide treatment of a polymeric resin to be used as a material of the membrane. Through the acid water treatment, the end of the polymer chain can be transformed into the H ⁺ form.

(2) stacking the first gasket and the second gasket

Step 2 is a step of laminating the first gasket 310 and the second gasket 320 on the upper and lower surfaces of the membrane 100 so that the outer edge of the membrane 100 covers the edge of the membrane 100.

The first gasket 310 and the second gasket 320 may be a polymer film, and specific types of the polymer resin used as the material of the first gasket 310 and the second gasket 320 are as described above.

(3) Formation of joints of the first gasket and the second gasket

Step 3 is a step of sealing the side edge of the membrane 100 by joining the outer ends of the first gasket 310 and the second gasket 320 together to form a joint.

As an example, the bonding may be performed by hot pressing, so that no additional adhesive may be required for the bonding. Specifically, the upper mold press and the lower mold press may be mounted on the protruded outer ends of the first gasket 310 and the second gasket 320 and thermally pressurized to form the joint.

As another example, the bonding may be performed by an adhesive. Specifically, an adhesive may be applied to the inner surface of the protruded outer end of the first gasket 310 and the second gasket 320 to form a joint.

The steps (2) and (3) may be performed simultaneously or sequentially. When the steps (2) and (3) are performed simultaneously, the first gasket 310 and the second gasket 320 are stacked on the upper and lower surfaces of the membrane 100, So that the joints can be formed.

(4) stacking electrodes

Step 4 is performed on the upper and lower surfaces of the membrane 100 so as to cover the center portion of the membrane 100 where the first gasket 310 and the second gasket 320 are not present. 220, respectively.

The lamination may be performed by a hot press process. The heat-pressing process may be performed at a temperature within a range of a transition temperature of a membrane, a gasket, and an adhesive applied thereto, and may be performed at a temperature of, for example, 150 deg.

In this step, the two electrodes 210 and 220 may be stacked on the upper and lower surfaces of the membrane, with their edge portions overlapping the first gasket 310 and the second gasket 320.

Through this step, a laminate is obtained in which the membrane 100, the two electrodes 210 and 220, the first gasket 310 and the second gasket 320 are tightly coupled by thermal pressurization.

On the other hand, the electrode used in this step

(2-1) fabricating a gas diffusion layer (GDL);

(2-2) forming a microporous layer (MPL) on the gas diffusion layer; And

(2-3) forming a catalyst layer (CL) on the microporous layer.

The gas diffusion layer (GDL) may be prepared by coating carbon paper with polytetrafluoroethylene (PTFE), for example. The PTFE is a fluoride-based polymer resin and can play a role of waterproofing and adhesion.

The microporous layer (MPL) may be prepared, for example, by coating carbon black and polytetrafluoroethylene (PTFE) on the gas diffusion layer and then heating.

The catalyst layer CL may be prepared, for example, by coating platinum (Pt) and an ionomer supported on activated carbon or the like on the microporous layer, followed by heating. The platinum may be, for example, several micrometers in diameter.

(5) Formation of third gasket and fourth gasket

Step 5 is a step of laminating the third gasket 330 and the fourth gasket 340 on the upper and lower surfaces of the joining portion of the first gasket 310 and the second gasket 320, respectively.

The third gasket 330 and the fourth gasket 340 may be a polymer film, and specific types of the polymer resin used as the material of the third gasket 330 and the fourth gasket 340 are as described above.

The third gasket 330 and the fourth gasket 340 may be stacked on the upper and lower surfaces of the joint by an adhesive.

Specifically, after the adhesive is applied to one surface of the third gasket 330 or the upper surface of the bonding portion, the third gasket 330 may be laminated on the upper surface of the bonding portion. Similarly, after the adhesive is applied to one surface of the fourth gasket 340 or the lower surface of the joining portion, the fourth gasket 340 may be laminated on the lower surface of the joining portion.

In addition, the third gasket 330 and the fourth gasket 340 may be laminated on the upper and lower surfaces of the joint by heat press, so that a separate adhesive may not be required at the time of lamination.

Each of the steps of the method according to the present invention can be carried out by reversing the order.

For example, the steps are performed in the order of steps (1), (2), (3) and (5), step (4) is performed between steps (3) and (5) (3), between steps (1) and (2), after step (5), or simultaneously with step (3).

6, a method of manufacturing a membrane-electrode assembly according to another example of the present invention

(1) fabricating a membrane 100;

(2) stacking a first gasket 310 and a second gasket 320 on the upper and lower surfaces of the membrane 100 such that the outer edge of the membrane 100 covers the edge of the membrane 100;

(3) Two electrodes 210 and 220 are formed on the upper and lower surfaces of the membrane 100 so as to cover the central portion of the membrane 100 where the first and second gaskets 310 and 320 are not present. Respectively;

(4) sealing the side edges of the membrane 100 by joining the outer ends of the first gasket 310 and the second gasket 320 together to form a joint; And

(5) stacking a third gasket 330 and a fourth gasket 340 on the upper and lower surfaces of the joint, respectively.

In this case, the two electrodes 210 and 220 are stacked on the upper and lower surfaces of the membrane 100, respectively, and at the same time, The outer ends of the first gasket 310 and the second gasket 320 may be joined to each other to form a joined portion.

Referring to Fig. 7, a method of manufacturing a membrane-electrode assembly according to another example

(1) fabricating a membrane 100;

(2) stacking a first gasket 310 and a second gasket 320 on the upper and lower surfaces of the membrane 100 such that the outer edge of the membrane 100 protrudes while covering the edge of the membrane 100;

(3) sealing the side edges of the membrane 100 by joining the outer ends of the first gasket 310 and the second gasket 320 together to form a joint;

(4) stacking a third gasket 330 and a fourth gasket 340 on the upper and lower surfaces of the joint, respectively; And

(5) Two electrodes 210 and 220 are formed on the upper and lower surfaces of the membrane 100 so as to cover the central portion of the membrane 100 where the first and second gaskets 310 and 320 are not present. Respectively.

In this case, the first gasket 310 and the second gasket 320 are stacked on the upper and lower surfaces of the membrane 100, respectively, And the joints can be formed by joining the outer ends thereof to each other by pressurization.

In this case, the third gasket 330 and the fourth gasket 340 may be formed on the first gasket 310 and the second gasket 320, respectively, And the outer ends of the heat dissipating plates are joined to each other by heat pressurization while being laminated on the outer end.

Referring to Fig. 8, a method of manufacturing a membrane-electrode assembly according to another example

(1) fabricating a membrane 100;

(2) stacking two electrodes 210 and 220 on the upper and lower surfaces of the membrane 100 so as to cover the center of the membrane 100, respectively; And

(3) The first gasket 310 and the second gasket 310 are formed on the upper surface and the lower surface of the membrane 100 so that the outer end of the membrane 100 covers the edge portion where the two electrodes 210 and 220 are not present, Stacking the gasket (320), respectively;

(4) sealing the side edges of the membrane 100 by joining the outer ends of the first gasket 310 and the second gasket 320 together to form a joint; And

(5) stacking a third gasket 330 and a fourth gasket 340 on the upper and lower surfaces of the joint, respectively.

In this case, the first gasket 310 and the second gasket 320 are stacked on the upper and lower surfaces of the membrane 100, respectively, And the joints can be formed by joining the outer ends thereof to each other by pressurization.

In this case, the third gasket 330 and the fourth gasket 340 may be attached to the first gasket 310 and the second gasket 320, And the outer ends of the heat dissipating plates are joined to each other by heat pressurization while being laminated on the outer end.

The present invention provides a fuel cell including the membrane-electrode assembly (MEA).

The fuel cell may include two or more MEAs. Specifically, the fuel cell may include a stack in which two or more MEAs are stacked. Further, a separator may be inserted between the stacked MEAs, and a gas or liquid passage for exchanging and transporting the MEAs may be provided in the separator plate.

By using the MEA of the present invention, the membrane can be completely prevented from being exposed to the outside, so that the water flow through the edge portion of the MEA can be completely blocked, and the height step due to the formation of the joint can be eliminated, The reliability is excellent. Accordingly, the fuel cell can be used in various fields such as a power source for an automobile, a household power generator, a mobile power source, and a military power source.

100: membrane, 210, 220: electrode,
310: first gasket, 320: second gasket,
330: third gasket, 340: fourth gasket,
350: fifth gasket, 360: sixth gasket,
t1, t2: total thickness, dh: height step.

Claims (12)

(a) a membrane;
(b) a first gasket, which is laminated on the upper and lower surfaces of the membrane so as to cover the edge of the membrane so that an outer end thereof protrudes, the outer ends of the gasket being joined to each other to seal a side edge of the membrane, 2 gasket;
(c) two electrodes stacked on the upper and lower surfaces of the membrane, respectively, so as to cover a central portion of the membrane where the first gasket and the second gasket are not present; And
(d) a third gasket and a fourth gasket which are stacked on the upper and lower surfaces of the joint, respectively.
The method according to claim 1,
The third gasket is stacked such that the upper surface thereof is located at the same height as the extension of the upper surface of the first gasket stacked on the upper surface of the membrane,
Wherein the fourth gasket is stacked such that its lower surface is located at the same height as an extension of the lower surface of the second gasket stacked on the lower surface of the membrane.
The method according to claim 1,
Wherein the third gasket has a thickness corresponding to a height difference between an upper surface of the first gasket stacked on the upper surface of the membrane and an upper surface of the joining portion,
Wherein the fourth gasket has a thickness corresponding to a height difference between a lower surface of the second gasket laminated on the lower surface of the membrane and a lower surface of the junction.
The method according to claim 1,
Wherein a total thickness t1 of a portion where the first gasket and the second gasket are laminated on the membrane and a total thickness t2 of a portion where the third gasket and the fourth gasket are laminated on the junction portion are equal to each other , Membrane-electrode assembly.
The method according to claim 1,
Wherein the third gasket and the fourth gasket are made of a polymer film.
6. The method of claim 5,
The polymer film may be a polymer resin selected from the group consisting of a polyphenylene sulfide resin, a polyester resin, a polyethylene resin, a polypropylene resin, a polyacrylonitrile resin, a polyvinyl chloride resin, an ethylene vinyl acetate resin, Wherein the membrane-electrode assembly comprises a membrane-electrode assembly.
The method according to claim 1,
Wherein the first gasket and the second gasket cover an edge portion of an area corresponding to 5% to 40% of the total area of the membrane,
Wherein the two electrodes cover a central portion of an area corresponding to 70% to 95% of the total area of the membrane.
The method according to claim 1,
The membrane-electrode assembly includes a fifth gasket stacked to cover both the upper surface of the first gasket and the upper surface of the third gasket; And a sixth gasket laminated to cover both the lower surface of the second gasket and the lower surface of the fourth gasket.
(1) preparing a membrane;
(2) stacking a first gasket and a second gasket on the upper and lower surfaces of the membrane, respectively, so that the outer end of the membrane covers the edge of the membrane;
(3) sealing the side edges of the membrane while joining the outer ends of the first gasket and the second gasket together to form a joint;
(4) stacking two electrodes on the upper and lower surfaces of the membrane, respectively, so as to cover a central portion of the membrane where the first gasket and the second gasket are not present; And
(5) laminating a third gasket and a fourth gasket on the upper and lower surfaces of the joint, respectively.
10. The method of claim 9,
Wherein the bonding of the outer ends of the first gasket and the second gasket is performed by a hot press.
10. The method of claim 9,
The steps are performed in the order of steps (1), (2), (3) and (5), wherein step (4) is performed between steps (3) and (5) (3), between the steps (1) and (2), after the step (5), or simultaneously with the step (3).
A fuel cell comprising the membrane-electrode assembly of claim 1.

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