KR101106924B1 - Stack for fuel cell - Google Patents

Abstract

The fuel cell stack of the present invention includes a membrane-electrode assembly (MEA) including an electrolyte membrane and an anode electrode and a cathode electrode positioned on both sides of the electrolyte membrane, respectively disposed on both sides of the MEA, and facing one side of the MEA. A plurality of gaskets disposed around an outer circumference of a region where the MEA is located to seal a space formed between the separator and the MEA and the separator, the plurality of gaskets including a first gasket having a first compression ratio; And a second gasket having a second compression ratio higher than the first compression ratio.

According to the present invention, the present invention introduces a dual structure of a first gasket having almost no compression characteristics and a second gasket having large compression characteristics to impart a constant surface pressure of the gas diffusion layer by the first gasket to maintain high performance of the fuel cell for a long time. It is possible to prevent the leakage of gas and coolant in the fuel cell operation by completely sealing the stack for the fuel cell by the second gasket. In addition, since the assembly of the gaskets without the addition of additional components there is an advantage that the assembly of the fuel cell stack does not deteriorate.

Stacks, gaskets for fuel cells

Description

Stack for fuel cell

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stack for a fuel cell, and more particularly, to a stack for a fuel cell in which a gasket installed to maintain airtightness in a unit cell that generates electricity has a dual structure.

A fuel cell is a power generation device that generates electrical energy by an oxidation reaction of a fuel and a reduction reaction of an oxidant gas separate from the fuel. For example, a polymer electrolyte fuel cell is a polymer electrolyte having a hydrogen ion exchange membrane characteristic. It is a fuel cell used as a membrane.

These fuel cells have many advantages, such as higher efficiency, higher current density and higher output density, shorter start-up time, and faster response to load changes than other types of batteries. It can be applied to a wide variety of fields such as spacecraft power, mobile power, military power.

Such a fuel cell has a unit cell which is a minimum unit for generating electrical energy. The unit cell is a membrane electrode assembly (hereinafter referred to as 'MEA'), a separator provided on both sides of the MEA, and a pair of separators positioned at the edge of the MEA. Includes a gasket to seal the space of the.

On the other hand, the MEA includes a gas diffusion layer which is a passage of fuel gas and water vapor, and whether the gas diffusion layer is properly compressed and whether the surface pressure is uniformly applied to the gas diffusion layer having a large area affects the performance and durability of the fuel cell stack. The compression rate of the gas diffusion layer is controlled through the gasket disposed outside the gas diffusion layer.

However, in the case of introducing a gasket made of a hard material layer having a high hardness, there is a limit in application since there is a risk of leaking gas and cooling water due to a minute gap between the gasket and the separator after the stack is fastened.

In addition, in the case of introducing a gasket made of a soft material layer having a low hardness, the compressibility of the gas diffusion layer cannot be smoothly controlled due to the properties of the gasket material, and due to the high elasticity of the gasket, it is applied to the gas diffusion layer during operation at high temperature. The pressure difference occurs locally, resulting in uneven surface pressure applied to the gas diffusion layer, resulting in localized non-uniform compression rate of the gas diffusion layer, and increased contact resistance at the gas diffusion layer and electrode interface due to uneven surface pressure. There is a problem that reduces the performance of.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide a stack for a fuel cell in which a gasket installed to maintain airtightness in a unit cell that generates electricity has a dual structure.

The fuel cell stack of the present invention includes a membrane-electrode assembly (MEA) including an electrolyte membrane and an anode electrode and a cathode electrode positioned on both sides of the electrolyte membrane, respectively disposed on both sides of the MEA, and facing one side of the MEA. A plurality of gaskets disposed around an outer circumference of a region where the MEA is located to seal a space formed between the separator and the MEA and the separator, the plurality of gaskets including a first gasket having a first compression ratio; And a second gasket having a second compression ratio higher than the first compression ratio, wherein the first gasket is disposed along an outer side of the separator, and the second gasket includes a manifold of the separator and the membrane-electrode assembly. Between the gas diffusion layer and the first gasket except for a through hole formed in a position and shape corresponding to the gas diffusion layer. It is intended to fill the space.

In addition, the first gasket may be disposed around an outer circumference of the second gasket.

In addition, the first compression ratio may be greater than 0 and less than or equal to 2%.

In addition, the second compression ratio may be 25 to 30%.

In addition, the first gasket and the second gasket may be integrally formed in close contact with each other.

In addition, the stack direction thickness of the first gasket before compression may be 70 to 75% of the stack direction thickness of the second gasket.

The apparatus may further include a membrane protective layer disposed between the plurality of gaskets and the electrolyte membrane.

In the fuel cell stack according to the present invention, a dual structure of a first gasket having almost no compression characteristics and a second gasket having large compression characteristics is introduced, and a constant surface pressure of the gas diffusion layer is given by the first gasket to provide high performance of the fuel cell. Can be maintained for a long time and the gas gasket can be prevented from leaking in the fuel cell operation by completely sealing the stack for the fuel cell by the second gasket.

In addition, since the assembly of the gaskets without the addition of additional components there is an advantage that the assembly of the fuel cell stack does not deteriorate.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a perspective view of a stack for a fuel cell according to an embodiment of the present invention, FIG. 2 is a perspective view of the anode separator shown in FIG. 1, and FIG. 3 is a cross-sectional view schematically showing a cross section of the MEA shown in FIG. 1.

As shown in FIG. 1, the stack 100 for a fuel cell of the present embodiment includes a unit cell 110 that receives electric fuel and an oxidant, and generates electrical energy by an oxidation reaction of a fuel and a reduction reaction of an oxidant gas. . Here, alcohol-based fuels such as methanol and ethanol are used as the fuel, and air is generally used as the oxidant gas.

The unit cell 110 is a minimum unit for generating electricity, and in order to generate electricity of a desired output, several to several tens of unit cells 110 are sequentially stacked to form a stack 100 for a fuel cell. . An end plate 101 is coupled to the outermost side of the fuel cell stack 100.

The unit cell 110 includes a membrane electrode assembly (hereinafter referred to as MEA 130) and separators 120 and 140 disposed on both surfaces of the MEA 130, respectively.

Referring to FIG. 3, the MEA 130 includes an anode electrode 130b and a cathode electrode 130c positioned on both surfaces of the electrolyte membrane 130a and the electrolyte membrane 130a, respectively.

In addition, the MEA 130 further includes a gas diffusion layer 131 which is a passage of fuel gas and water vapor. The material of the gas diffusion layer 131 is carbon paper, carbon cloth, or the like, and has electrical conductivity, porosity, and elasticity.

Here, the compression rate of the gas diffusion layer 131 is preferably 10 to 50%, more preferably 20 to 35%.

When the gas diffusion layer 131 is not compressed, the gas (fuel, air), which is the original purpose, may be smoothly transferred to the electrodes 130b and 130c of the MEA 130 to increase electrode performance, and may be generated by an electrochemical reaction. Although the discharged water can be smoothly discharged, the interface resistance between the gas diffusion layer 131 and the electrodes 130b and 130c becomes high unless compressed in the fuel cell stack 100.

Therefore, since the compression ratio of the gas diffusion layer 131 is inversely related to the gas flow / exit and interface resistance, proper compression is necessary in consideration of this, and in the present invention, the compression ratio of the gas diffusion layer 131 is determined in order to achieve such an object. As a limit to 10 to 50%, preferably 20 to 35%. The degree of compression of the gas diffusion layer 131 is adjusted through the gaskets 151 and 152 to be described later.

The anode electrode 130b oxidizes fuel to separate electrons and hydrogen ions. The electrolyte membrane 130a moves the hydrogen ions to the cathode electrode 130c, and the cathode electrode 130c reduces the hydrogen ions with the oxidant gas.

Meanwhile, the separators 120 and 140 have a plate shape, and the first separator 120 is a cathode separator, and a channel is formed on one surface of the MEA 130 facing the cathode electrode 130c side. The second separator 140 is an anode separator, and a channel is formed on one surface of the MEA 130 facing the anode electrode 130b side.

Since the first separator 120 and the second separator 140 have the same shape, only the second separator 140 will be described below.

Referring to FIG. 2, in the separator 140 of this embodiment, a channel 141 is formed on one surface thereof, and fuel flows along the channel 141. The region where the channel 141 is formed is a dotted line region 142 of FIG. 2 and faces an MEA 130 shown in FIG. 1. The channel 141 is divided into a plurality of partitions 143.

The separator 140 is formed such that the manifolds 144 and 145 penetrate outside the region where the channel 141 is formed. Since the stack 100 for the fuel cell has a structure in which a plurality of separators 120 and 140 are stacked, the manifolds 144 and 145 serve as one flow path. Fuel is introduced through the first manifold 144 and unreacted fuel is discharged through the second manifold 145.

In the present exemplary embodiment, the first manifold 144 into which the fuel is introduced into the separator 140 and the second manifold 145 into which the unreacted fuel is discharged are provided, but the present invention is not limited thereto. In addition, a plurality of manifolds may be formed in one separator.

4 is an exploded perspective view illustrating the anode separator and the gaskets shown in FIG. 1, FIG. 5 is a cross-sectional view schematically illustrating a stacked state of the stack for the fuel cell illustrated in FIG. 1, and FIG. 6 is a stack for the fuel cell illustrated in FIG. 5. When the pressure is applied to the upper and lower unit cells of the cross-sectional view schematically showing the stacking state of the fuel cell stack.

As shown in Figs. 4 and 5, the fuel cell stack 100 of this embodiment is disposed around the outer periphery of the area where the MEA 130 is located, so that the MEA 130 and the pair of separators 120 and 140 are located. It includes a plurality of gaskets (151, 152) sealing the space between.

Referring to FIG. 4, the plurality of gaskets 151 and 152 are formed in a sheet type that can be in close contact with the separators 120 and 140, and the outer circumference of the region where the channel 141 of the separators 120 and 140 is formed. Is placed on.

In the second gasket 152, first through holes 152a and 152b are formed to correspond to the manifolds 144 and 145 of the separators 120 and 140, and the dotted line region 142 and the MEA 130 of FIG. 2 are formed. The second through hole 152c corresponding to the region is formed inside.

In the present exemplary embodiment, the first through holes 152a and 152b and the second through hole 152c are described as being formed in the second gasket 152. However, the present invention is not limited thereto, and the first through holes and the second through holes are not limited thereto. A hole may be formed in the first gasket 151, and a part of the through holes 150a, 150b, and 150c may be variously formed in one of the first gasket 151 and the second gasket 152. You can change the design.

In the fuel cell stack 100 of the present embodiment configured as described above, a plurality of unit cells 110 are stacked, and the MEA 130 is located in the second through hole 152c. Fuel is then introduced or discharged through the manifolds 144 and 145.

Referring to FIG. 5, the second gasket 152 of the present exemplary embodiment is disposed around the outer circumference of the region where the MEA 130 is located, and the first gasket 151 is disposed around the outer circumference of the second gasket 152. The two gaskets 152 are arranged in parallel with each other.

As shown in FIG. 5, the double gasket structure including the first gasket 151 and the second gasket 152 may have any shape such as a circle, a rectangle, a triangle, and an oval.

Meanwhile, the plurality of gaskets 151 and 152 of the present invention each have a certain amount of compression ratio in order to seal the space between the separators 120 and 140, and in particular, the plurality of gaskets have different compression ratios. And a second gasket 152.

Here, when the compression rate of the first gasket 151 is called a first compression rate and the compression rate of the second gasket 152 is called a second compression rate, the second compression rate is higher than the first compression rate. That is, the gaskets 151 and 152 of the present embodiment are made of a material having different hardness and compression ratio.

The first gasket 151 is made of a hard material layer having a high hardness and a low compression rate, and the second gasket 152 is a soft material layer having a relatively low hardness and a high compression rate compared to the hard material layer. Is done.

Here, the hard material layer is made of metal, polyethylene terephthalate (PET), polyethylene naphthelate (PEN) material, and the soft material layer is Teflon, polytetrafluoroethylene ( It is made of PTFE (Polytetrafluoro ethylene) and ethylene propylene rubber (EPDM) and has a high compression ratio and is compressed by the clamping force of the separators 120 and 140.

The first compression ratio is ideally 0 to minimize the compression of the first gasket 151, but limited to 2% or less in consideration of the properties of the material.

The second compression ratio is preferably 10 to 50% for variety of material selection, and more preferably 25 to 30% in consideration of sealing and durability.

On the other hand, when the second gasket 152 is reduced in thickness by about 25 to 30% from the original thickness (t ₂ ), not only the sealing ability is excellent, but also the durability of the material by compression is considered in consideration of this, The stack direction thickness t ₁ before compression of the gasket 151 is set to 70 to 75% of the stack direction thickness t ₂ of the second gasket 152.

Referring to FIG. 6, when a predetermined pressure is applied in the double gasket structure having the structure of FIG. 5, the plurality of gaskets 151 and 152 may be in close contact with the separators 120 and 140 in the compression process.

At this time, the gas diffusion layer 131 is compressed by the thickness t _{1 of} the first gasket 151, the first gasket 151 substantially maintains the original thickness t ₁ , and the second gasket 152. Is contracted by the thickness t _{1 of} the first gasket 151 to fill the gap between the first gasket 151 and the gas diffusion layer 131.

In this case, the entire surface of the gas diffusion layer 131 is supported by the first gasket 151 made of a hard material layer to transmit a predetermined thickness and a constant surface pressure to the electrodes 130b and 130c, and made of a soft material layer. The second gasket 152 fills the gap between the first gasket 151 and the gas diffusion layer 131 to achieve a perfect sealing.
In other words, as shown in FIG. 4, the first gasket 151 is formed in the same shape while maintaining a constant thickness along the outer side of the separator 140 so as to surround the outside of the separator 140. 152 is formed to fill the space formed between the first gasket 151 and the gas diffusion layer 131 when the stack 100 is assembled, the second gasket 152 is a manifold (144,145) of the separator 140 ) And the first through holes 152a and 152b and the second through hole 152c are opened at positions corresponding to the gas diffusion layers 131 of the MEA 130 and the gas diffusion layers 131, respectively. Of course, to prevent the leakage of gas flowing in / out through the manifold (144,145).

Therefore, according to the present invention, the first gasket 151 can impart a constant surface pressure of the gas diffusion layer to maintain high performance of the fuel cell for a long time, and the fuel cell stack 100 can be perfectly formed by the second gasket 152. Sealing has the effect of preventing gas and cooling water leakage in fuel cell operation.

Specifically, when a gasket composed of only a hard material layer having a high hardness is introduced, there is a risk of leaking gas and cooling water through a minute gap between the gasket and the separator after the stack for the fuel cell is fastened. According to the present invention, since the second gasket made of the soft material layer is provided inside the first gasket, the gap between the gasket and the gas diffusion layer and the gasket and the separator can be filled well to maximize the sealing effect. And the risk of leakage of cooling water is advantageous.

In addition, when a gasket composed of a soft material layer having low hardness is introduced, the compressibility of the gas diffusion layer cannot be smoothly controlled due to the properties of the gasket material, and the high elasticity of the gasket prevents the gas diffusion layer from operating at high temperatures. There is a problem in that the pressure applied locally causes a nonuniform surface pressure to be applied to the gas diffusion layer, thereby increasing the contact resistance at the gas diffusion layer and the electrode interface, thereby degrading the performance of the unit cell.

However, in the present invention, the gas diffusion layer 131 in consideration of the proper compression of the gas diffusion layer 131 of the MEA 130 and the surface pressure applied to the gas diffusion layer having a large area affects the performance and durability of the fuel cell stack. The degree of compression can be adjusted through the first gasket 151.

That is, according to the present invention, since the first gasket made of a hard material layer is provided on the outside of the second gasket, the gas diffusion layer may be compressed by the thickness of the first gasket, and thus the gas diffusion layer may be controlled by adjusting the thickness of the first gasket. You can compress as much as you want.

As described above, the present invention overcomes the limitations of the gasket composed only of the hard material layer and the gasket composed only of the soft material layer, and has the advantages of the respective gaskets. It can be stably exhibited.

On the other hand, the first gasket 151 of the present invention is disposed around the outer periphery of the second gasket 152 and is disposed parallel to the second gasket 152 in a horizontal direction.

Compared to the vertical structure having a thin second gasket 152 above or below the first gasket 151, this vertical structure constitutes the soft material of the second gasket 152 introduced above or below. Due to the nature of the layer, if the local uniform force is not applied to the outermost part of the separators 120 and 140 after fastening the stack 100 for the fuel cell, the compression ratio is turned and the MEA 130 stacked on the separator 120 and 140 channels. It is impossible to give a uniform surface pressure to), thereby increasing the contact resistance between the MEA (130) and the separator (120, 140), causing a fatal problem that degrades the stack performance.

In addition, since additional equipment must be built in order to introduce the second gasket 152 on the upper or lower portion of the first gasket 151, the production cost increases, and the first gasket 151 and the second gasket 152 move upward and downward. When stacked and integrally provided, the gap is generated due to the difference in elasticity between the first gasket 151 and the second gasket 152 under long fuel cell operating conditions, and gas and cooling water leak during long time operation of the fuel cell.

In addition, in order to maintain a constant thickness even under non-uniform pressure, the thickness of the second gasket 152 disposed above or below the first gasket 151 should be approximately 10 μm or less, in this case 10% at a thickness of 10 μm. In order to meet the thickness tolerance, there is a problem that is followed by a very difficult process of adjusting the thickness between 1 μm.

On the other hand, in the structure in which the first gasket 151 is disposed around the outer circumference of the second gasket 152 and arranged horizontally parallel to the second gasket 152 as in the present invention, the software forming the second gasket 152 is soft. It is easy to manufacture the gasket by adjusting the thickness of one material layer to a thickness of 200 to 350 μm before compression, and the assembly of the fuel cell stack does not deteriorate because the gaskets are assembled without additional components. There is this.

According to the above structure, the contact resistance between the MEA 130 and the separators 120 and 140 is increased by introducing a first gasket 151 at the outermost of the separators 120 and 140 to prevent non-uniform surface pressure and maintaining a constant surface pressure in the gas diffusion layer. Can be prevented and the gas diffusion layer 131 can be protected.

In addition, by introducing the second gasket 152 inside the first gasket 151, the gas may be prevented from leaking between the separators when the gas is introduced into or discharged from the manifolds 144 and 145 to the channel 141. That is, in the present invention, since gas leakage occurs between the manifolds 144 and 145 of the separator or between the manifolds 144 and 145 and the channel 141, a second gasket 152 having a sealing ability is provided to the inside first. will be.
Meanwhile, although the first gasket 151 and the second gasket 152 are separately manufactured and arranged in FIGS. 5 and 6, the first gasket 151 and the second gasket 152 may be formed in close contact with each other to be integrally formed. Can be.

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When the first gasket 151 and the second gasket 152 are brought into close contact with each other and integrally formed, a gap occurs between the first gasket 151 and the second gasket 152 even when the second gasket 152 is expanded. By doing so, the sealing ability can be further improved.

The fuel cell stack 100 of the present embodiment may further include a membrane protecting layer 160 disposed between the plurality of gaskets 151 and 152 and the electrolyte membrane 130a.

By disposing the membrane protective layer 160 above and below the electrolyte membrane 130a, the membrane may be protected by preventing external exposure of the electrolyte membrane 130a made of a polymer electrolyte. In addition, swelling expansion of the electrolyte membrane 130a may be prevented and the electrolyte membrane 130a may secure a certain level of strength.

Hereinafter, it will be described in contrast to the embodiment and the comparative example of the above-described stack for a fuel cell of the present invention.

First, a 280 μm-thick polyethylene terephthalate (PET) film is cut using a wooden mold to prepare a first gasket 151, and a 400 μm thick thermoplastic rubber is used to cut an ethylene propylene rubber (EPDM) sheet using a wooden mold. To prepare a second gasket 152.

The cut second gasket 152 is mounted at a position outside the channel of the separators 120 and 140 at a position, and a first gasket 151 coated with spray adhesive is mounted on the outside of the second gasket 152. .

Thereafter, the gas diffusion layers 131 of the MEA 130 are mounted on the channel portions of the separators 120 and 140 on which the first and second gaskets are mounted, thereby separating the separators 120 and 140, the first gasket, the second gasket, and the gas. The diffusion layer 131 is completed in one piece, and the integrated pieces are sequentially stacked to complete a stack of tens of cells.

In comparison, the comparative example used one gasket, not a plurality of gaskets, and the gasket was manufactured by cutting an ethylene propylene rubber (EPDM) sheet by using a wooden mold with a 400 μm thick thermoplastic rubber, It is the same as the second gasket.

7 is a graph showing the voltage-current performance of the fuel cell produced by the examples and comparative examples of the present invention.

Here, the fuel cell performance evaluation conditions are as follows. Temperature (based on stack outlet temperature) of the fuel cell stack obtained in the above examples and comparative examples: 65 ° C., cooling water: 2.5 LPM (Liter / Minute), fuel utilization rate: 80%, air utilization rate: 60%, fuel gas supplied ( Relative humidity of hydrogen) (anode relative humidification): 95%, relative humidity of the supplied oxidant gas (cathode relative humidification): evaluated at 95%. Here, the relative humidity was all based on the stack outlet temperature.

Referring to FIG. 7, in the case of the embodiment, it is confirmed that the stack average voltage V corresponding to the current value of the specific region is higher than that of the comparative example.

The reason for this is that in the comparative example, since the gasket material is a soft material layer, the compressibility of the gas diffusion layer 131 cannot be smoothly controlled due to its physical properties, and the pressure applied to the gas diffusion layer 131 during high temperature operation due to the high elasticity of the gasket. This is because of local differences. As a result, the surface pressure applied to the gas diffusion layer 131 becomes uneven, and the contact resistance at the interface between the gas diffusion layer 131 and the electrode increases, thereby degrading the performance of the unit cell.

In contrast, in the case of the embodiment of the present invention, the gas diffusion layer 131 of the MEA 130 is properly compressed by using a dual structure gasket so that the surface pressure applied between the gas diffusion layer 131 and the electrode is uniform so as to stack the fuel cell stack. The performance of the was improved.

FIG. 8 is a graph showing a voltage decay ratio under a short-term constant current operating condition of a fuel cell manufactured by Examples and Comparative Examples of the present invention.

Here, the performance evaluation conditions of the present experiment was the same as the performance evaluation conditions, and the durability was tested by measuring the degree of voltage drop in the constant current 43 (A).

Observing the long-term performance improvement effect of the double gasket structure from FIG. 8, it can be seen that in the comparative example using only the second gasket, the stack voltage drastically decreases with time and the degree of reduction is irregular.

On the other hand, the embodiment not only has excellent initial performance, but also shows a significant improvement in durability compared to the comparative example due to a decrease in performance over time.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a perspective view of a stack for a fuel cell according to an embodiment of the present invention;

FIG. 2 is a perspective view of the anode separator shown in FIG. 1;

3 is a cross-sectional view schematically showing a cross section of the MEA shown in FIG. 1;

4 is an exploded perspective view illustrating the anode separator and the gaskets shown in FIG. 1;

FIG. 5 is a cross-sectional view schematically illustrating a stacked state of the stack for the fuel cell illustrated in FIG. 1;

FIG. 6 is a cross-sectional view schematically illustrating a stacking state of a fuel cell stack when pressure is applied to upper and lower unit cells of the fuel cell stack shown in FIG. 5;

7 is a graph showing the voltage-current performance of the fuel cell produced by the embodiment and the comparative example of the present invention,

8 is a graph showing the degree of voltage drop (Vlotage Decay Ratio) in the short-term constant current operating conditions of the fuel cell produced by the embodiment and the comparative example of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig.

100: fuel cell stack 110: unit cell

120, 140: separator 130: membrane-electrode assembly (MEA)

151: first gasket 152: second gasket

Claims (7)

A membrane-electrode assembly (MEA) comprising an electrolyte membrane and an anode electrode and a cathode electrode respectively positioned on both surfaces of the electrolyte membrane; Separators disposed on both sides of the MEA and having channels formed on one surface of the MEA opposite to each other; And A plurality of gaskets disposed around an outer circumference of an area in which the MEA is located to seal a space between the MEA and the separator, The gaskets include a first gasket having a first compression ratio and a second gasket having a second compression ratio higher than the first compression ratio. The first gasket is disposed along an outer side of the separator, and the second gasket has a gas diffusion layer except for through holes formed in positions and shapes corresponding to the gas diffusion layer of the separator and the manifold of the separator. And filling the space between the first gasket and the fuel cell stack. The method according to claim 1, And the first gasket is disposed around an outer circumference of the second gasket. The method according to claim 1, The first compression ratio is greater than 0 and 2% or less, the stack for a fuel cell. The method according to claim 1, The second compression ratio is a fuel cell stack, characterized in that 25 to 30%. The method according to claim 1, The first gasket and the second gasket are in close contact with each other formed integrally with the fuel cell stack. The method according to claim 1, The stack direction thickness of the first gasket before compression is 70 to 75% of the stack direction thickness of the second gasket. The method according to claim 1, And a membrane protection layer disposed between the plurality of gaskets and the electrolyte membrane.

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