JP2003203645A - Separator for polymer electrolyte fuel cell and fuel cell using the same - Google Patents

Abstract

(57) [Problem] To provide a separator for a polymer electrolyte fuel cell. A positive electrode and a negative electrode are provided on both sides of an electrolyte membrane.
b, and a separator for a polymer electrolyte fuel cell including a separator for sandwiching the unit cell, supplying a fuel gas to the positive electrode side, and supplying an oxidizing gas to the negative electrode side, has a gas-impermeable property. The conductive porous body 16 having a gas-impermeable peripheral part for supplying the fuel gas to the positive electrode is provided on one side of the conductive partition plate 21 and the oxidant gas is supplied to the negative electrode on the other side. A separator for a polymer electrolyte fuel cell, in which a gas-impermeable conductive porous body 17 is disposed in a peripheral portion to be supplied, and these three plates are integrated by a conductive adhesive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid polymer fuel cell separator, and more particularly to a low cost separator which is easy to assemble and a fuel cell using the same.

[0002]

2. Description of the Related Art Fuel cells are classified into solid polymer fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, solid oxide fuel cells, etc., depending on the electrolyte used.

The polymer electrolyte fuel cell has a higher current density than other fuel cells, a long life, less deterioration due to start / stop, a low operating temperature (about 80 ° C.), and easy operation control. Because it has advantages such as stationary, household power supply,
A wide range of applications such as automobile power supplies are expected.

FIG. 6 is a schematic cross-sectional view showing an example of the structure of a solid polymer electrolyte fuel cell single cell using a conventional graphite separator. The electrolyte membrane 1 made of a solid polymer has a thickness of 20 to 50 μm and a rectangular shape with one side of 10 to 15 cm. As the electrolyte membrane 1, perfluorosulfonic acid resin (eg, Nafion membrane manufactured by DuPont, Aciplex membrane manufactured by Asahi Kasei, Flemion membrane manufactured by Asahi Glass Co., Ltd.) is known at present. The electrolyte membrane 1 is a polymer membrane having a proton (hydrogen ion) exchange group in the molecule, and has a resistivity of 20 Ωcm or less at room temperature when saturated with water.

On one side of the electrolyte membrane 1, there is an anode (positive electrode) 3a which is in close contact with the electrolyte membrane 1 and is supplied with hydrogen or a fuel gas containing hydrogen at a high concentration, and on the other side of the electrolyte membrane 1. There is a cathode (negative electrode) 3b which is closely supplied with and is supplied with an oxidant gas containing air or oxygen at a high concentration. The anode 3a and the cathode 3b have a thickness of 10
It is composed of a porous graphite particle layer supporting fine Pt or Pt alloy catalyst with a thickness of μm, and is often baked on the electrolyte membrane 1 by hot pressing or the like.

An anode side gas diffusion layer 5a and a cathode side gas diffusion layer 5b are arranged outside the anode 3a and the cathode 3b. In the gas diffusion layers 5a and 5b,
A water-repellent carbon cloth having a thickness of 200 to 400 μm or the like is used.

The electrolyte membrane 1 and the gas diffusion layers 5a and 5b arranged on both sides thereof are sandwiched by the separators 2a and 2b. On the side where the anode-side separator 2a and the anode-side gas diffusion layer 5a are in contact with each other, a fuel gas passage 7 for supplying a fuel gas such as hydrogen to the anode 3a is provided.
An oxidant gas flow path 6 for supplying an oxidant gas such as air to the cathode 3b is provided on the side where the cathode side separator 2b and the cathode side gas diffusion layer 5b are in contact with each other.

The fuel gas and the oxidant gas are sealed by gaskets 4a and 4b, respectively. The gas passage has a width of about 1 mm and a depth of about 1 mm, and is often formed with a pitch of about 1 mm. The polymer electrolyte fuel cell stack is formed by stacking several tens of the above-mentioned single cells. The electrode reaction is as follows. [Equation 1] Anode side: H ₂ → 2H ⁺ + 2e ⁻ Cathode side: 2H + ½O ₂ + 2e ⁻ → H ₂ O Conventionally, a gas-impermeable treated graphite plate has been used as a separator material.

[0009]

As described above, the polymer electrolyte fuel cell has a high current density, a long life, and
Since it has advantages such as low operating temperature (about 80 ℃), it is attracting attention as a stationary and household power supply, automobile power supply, etc., but the biggest issue for market acceptance is cost reduction. is there. Costs consist of material costs, processing costs, stack assembly costs, etc., and reducing these costs is an important issue.

A conventional graphite separator is required to be impervious to gas by impregnating graphite pores with a resin such as phenol and then heat-treating at a high temperature of more than 1000 ° C. to carbonize the material. It is expensive by itself. In addition, it takes a long time to make a gas flow path for supplying a fuel gas (H ₂ or the like) or an oxidant gas (air or the like) to the electrolyte membrane in the obtained dense graphite plate by mechanical cutting. Becomes expensive.

Further, as shown in FIG. 6, since the unit cell has a large number of components including the electrolyte membrane 1 with electrodes, the diffusion layers 5a and 5b, the gaskets 4a and 4b, and the separators 2a and 2b, there are a large number of components. Assembling and inspecting a stack having a cell number of several tens of layers requires labor and time, resulting in high cost.

As a method for improving the processing cost, Japanese Patent Laid-Open No. 8-255619 proposes a method of using porous carbon having a three-dimensional mesh for a gas supply plate (flow distribution plate). This method does not require mechanical cutting of the gas flow path, so the processing cost is low. However, the number of parts of a single cell is one electrolyte membrane and two porous carbon plates.
7 gaskets, 2 gaskets, 2 separators,
If a conductive sheet is sandwiched between the separator and the gas distribution plate to reduce the contact resistance, there will be a total of 9 parts.

As described above, since the number of parts is large and a gap is formed between the gasket and the porous carbon plate, the gas is unevenly flown, so it is necessary to fit the gap without gap, and it takes a long time to assemble and inspect. High cost.

In view of the above, an object of the present invention is to provide a low cost solid polymer fuel cell separator having characteristics equal to or better than those of conventional ones, and a solid polymer fuel cell using the same. is there.

[0015]

The gist of the present invention for achieving the above object is as follows.

A unit cell in which a positive electrode and a negative electrode are arranged on both sides of a solid polymer electrolyte membrane and a separator for sandwiching the unit cell and supplying a fuel gas to the positive electrode side and an oxidant gas to the negative electrode side are provided. The separator of the polymer electrolyte fuel cell has a gas-impermeable conductive partition plate as a center, and a gas-impermeable conductive porous plate is provided on one side of the partition plate for supplying fuel gas to the positive electrode. On the other side of the body plate, a gas impermeable conductive porous body plate is arranged on the other side for supplying the oxidant gas to the negative electrode, and these three plates are integrated by a conductive adhesive. It is characterized by

Further, a solid polymer having a unit cell in which a positive electrode and a negative electrode are arranged on both sides of an electrolyte membrane and a separator for sandwiching the unit cell and supplying a fuel gas to the positive electrode side and an oxidant gas to the negative electrode side. Type fuel cell, the separator has a gas impermeable conductive partition plate as a center, and a peripheral portion for supplying fuel gas to the positive electrode on one side of the partition plate is a gas impermeable conductive porous body. On the other side of the plate, a gas impermeable conductive porous plate is arranged on the other side for supplying the oxidant gas to the negative electrode, and these three plates are integrated by a conductive adhesive. The fuel cell is characterized in that

In the above, the gas-impermeable conductive partition plate is a stainless steel plate or a resin-molded carbon plate coated with a corrosion-resistant conductive paint, and the conductive porous plate is a carbon cloth. It is achieved by using a separator having a porosity of 60 to 80%.

The separator of the present invention is a conductive porous material for supplying fuel gas, which has a gas-impermeable conductive plate for partitioning the fuel gas and the oxidant gas, and the periphery of which is made gas-impermeable by a resin mold. A body plate (hereinafter, referred to as a fuel gas supply plate) and a conductive porous body plate for supplying an oxidant gas (hereinafter, referred to as an oxidant gas supply plate) whose periphery is made gas impermeable by a resin mold are arranged. The three plates are integrated via a conductive adhesive.

A gas-impermeable conductive plate for partitioning the fuel gas and the oxidant gas (hereinafter referred to as a conductive gas partition plate)
Retains its shape, does not allow gas to permeate, has electrical conductivity (resistance per unit area of several mΩcm ² or less), and
Since it is used in an environment near saturated steam pressure of about 80 ° C, especially in the presence of air (oxygen) on the cathode side, a material with excellent corrosion resistance is preferable, and low cost is required. Is preferably stainless steel coated with a corrosion-resistant conductive paint, and a carbon-based resin-molded carbon plate is preferable.

Materials such as carbon steel, copper, and aluminum can be used by coating the surface with a corrosion-resistant conductive paint, but since these metal materials are less corrosive than stainless steel, the corrosion-resistant conductive paint is used. If the coat layer has defects such as pinholes, it is easily corroded, which is not preferable.

If a conductive porous body whose periphery is gas impermeable by resin molding is used as a member for supplying the fuel gas or the oxidant gas to the electrolyte membrane, the gas for supplying the fuel gas and the gas for supplying the oxidant gas are used. Since the mechanical cutting process for forming the flow path is not necessary, the processing cost is low.

As the conductive porous body, a metal punch plate coated with a corrosion-resistant conductive paint, various wire nets, carbon-based carbon cloth, carbon felt or the like can be used, but carbon-based carbon is used in terms of reliability against corrosion. A cloth is preferable and the cost is low.

The resin having a gas impermeable function in the peripheral portion of the conductive porous body is required to have a gas sealing property and therefore has elasticity, and is used in an environment close to a saturated water vapor pressure of about 80 ° C. Therefore, it is necessary to have corrosion resistance against steam. As such a material, a rubber material such as butyl rubber, butadiene rubber, fluororubber, and silicone rubber is preferable.

The conductive adhesive is prepared by mixing a conductive filler and a resin. As the conductive filler, graphite powder, metal powder such as Au, Ag, Fe and Al, W
There are conductive ceramic powders such as C, TiC, TiN, TiB, and FeSi. Graphite powder is the most suitable because it is inexpensive, has a relatively low resistivity, and has excellent corrosion resistance and oxidation resistance at 80 ° C.

The Au and Ag powders are expensive, and the Fe and Al powders are not preferable because they are oxidized in the fuel cell operating environment to increase the resistance. Further, the conductive ceramics have a resistivity of the order of about 10 ⁻⁵ Ωcm, which is larger than metals such as Au and Ag but smaller than graphite. However, borides and nitrides are not preferable because they have low oxidation resistance. Silicide is excellent in oxidation resistance, but it is costly. Since WC and TiC have low resistivity and excellent resistance to oxidation, they can be used although the cost is somewhat high.

Examples of the resin include thermoplastic vinylidene fluoride resin, thermosetting phenol resin, epoxy resin and the like. The mixing ratio of the conductive filler to the resin is 15 to 15.
40 vol% is good. If it is less than 15 vol%, the conductivity will be poor. On the other hand, if it exceeds 40 vol%, voids are likely to be formed, so that the gas sealability is deteriorated. Also, the bonding strength of the thin metal plates is reduced.

Since the conductive porous plate and the gas partition plate for supplying the fuel gas and the oxidant gas to the electrolyte membrane are bonded and integrated by the conductive adhesive, the number of parts of the single cell is the fuel gas supply separator. 1 piece, electrolyte membrane 1 piece,
The oxidant gas supply separator may be composed of three parts, and the number of parts when assembling the stack can be greatly reduced, so that the stack assembling cost becomes low.

[0029]

1 is a top view of a separator in which a fuel gas supply plate, a conductive gas partition plate and an oxidant gas supply plate of the present invention are integrated with a conductive adhesive.

The separator of this embodiment is manufactured by integrating the fuel gas supply plate 11, the conductive gas partition plate 21, and the oxidant gas supply plate 31 with a conductive adhesive.

The fuel gas supply plate 11, the conductive gas partition plate 21, and the oxidant gas supply plate 31 penetrate through the fuel gas supply plate 11, the conductive gas partition plate 21, and the oxidant gas supply plate 31 in the thickness direction, respectively.
3, oxidant gas supply hole 14 and oxidant gas discharge hole 15
Is provided.

Fuel gas supply hole 12 of fuel gas supply plate 11
The fuel gas supplied to the fuel gas supply plate 11 flows through the conductive porous body 16 to supply the fuel gas to a solid polymer electrolyte membrane (not shown) that is in contact with the fuel gas supply plate 11 and discharge the fuel gas. It is discharged to the outside of the system through the hole 13.

The outflow of the fuel gas to the oxidant gas supply hole 14 and the oxidant gas discharge hole 15 is sealed by the gas impermeable resin mold parts 18a and 18b. The oxidant gas supplied to the oxidant gas supply hole 14 of the oxidant gas supply plate 31 flows through the conductive porous body 17 of the oxidant gas supply plate 31,
The oxidant gas is supplied to the solid polymer electrolyte membrane (not shown) in contact with the oxidant supply plate 31, and the oxidant gas discharge hole 15 is provided.
Is discharged to the outside of the system.

On the other hand, the outflow of the oxidant gas to the fuel gas supply hole 12 and the fuel gas discharge hole 13 is sealed by gas impermeable resin mold parts 18c and 18d.

The fuel gas supply plate 11, the conductive gas partition plate 21 and the oxidant gas supply plate 31 are integrated with each other through a conductive adhesive.

Example 1 Next, an example of a specific method for producing the separator shown in FIG. 1 will be described. The conductive gas partition plate 21 has a length of 100 mm × a width of 100 mm ×
A SUS304 steel thin plate having a thickness of 0.5 mm was used. Also,
In the fuel gas supply plate 11 and the oxidant gas supply plate 31,
Using a carbon cloth having a length of 100 mm × width of 100 mm × thickness of 0.5 mm and a porosity of about 70%, silicone rubber was molded in a width of 4 mm to 10 mm.

Each plate is provided with a fuel gas supply hole 12, a fuel gas discharge hole 13, an oxidant gas supply hole 14, and an oxidant gas discharge hole 15 each having a width of 3 mm and a length of 60 mm at a position 5 mm from four sides. Two sets of through holes formed by the press punching method were prepared.

Next, 1000 g of vinylidene fluoride resin (N-methylpyrrolidone 12 wt% solution) manufactured by Kureha Chemical Co., Ltd.
In addition, 90 g of graphite powder having an average particle diameter of 3 μm and 30 g of carbon black fine powder (carbon powder / vinylidene fluoride resin = 50 /
50 weight ratio) was added and kneaded with a three-roll mill to prepare a conductive adhesive.

This conductive adhesive was applied to SU by the dip method.
After applying to both sides of S304 partition plate, 150 x 15
The fuel gas supply plate 11 placed on a SUS304 plate having a thickness of 0 mm and a thickness of 10 mm is laid on top of the oxidant gas supply plate 31.
A 0 mm SUS304 plate is placed, and heat treatment is performed at a reduced pressure of 1 Torr or less at 150 ° C. for 15 minutes, 250 ° C. for 15 minutes, and a fuel gas supply plate 11 and a conductive gas partition plate 21.
And an oxidant gas supply plate 31
A set was made.

This is arranged as shown in FIG.
It was sandwiched between 20 × 120 × 10 mm SUS plates 19 and tightened with bolts to produce a single cell.

As the electrolyte membrane 1, an electrolyte membrane manufactured by Japan Gore-Tex Co. having a thickness of about 30 μm was used. A Pt-based catalyst supported on graphite particles is baked on both surfaces of the electrolyte membrane 1. Humidified hydrogen gas was supplied to the fuel electrode side and humidified air was supplied to the air electrode side, and the I / V characteristics were evaluated under the conditions of 70% hydrogen utilization rate, 40% air utilization rate and 70 ° C.

FIG. 3 is a graph showing the characteristics of a single cell using the above separator. Note that, in FIG. 3, for comparison, 100 mm × 100 mm × thickness of about 5 mm according to the related art.
The results of using a separator in which a gas passage having a width of 1 mm and a depth of 1 mm is formed by mechanical cutting at a pitch of 1 mm on the artificial graphite plate of 3 are also shown.

The single cell using the separator according to the present embodiment is the comparative example 1 using the graphite separator according to the prior art.
The same current density / voltage characteristics were obtained as compared with the above. As a result, the peripheral portion of the present invention is made gas impermeable by the silicone rubber mold, and the fuel gas supply plate 11 made of carbon cloth, the electrically conductive gas partition plate 21 made of stainless steel, and the peripheral portion are made gas impermeable by the silicone rubber mold. It can be seen that the integrally joined separator made of graphite powder / vinylidene fluoride conductive adhesive and the oxidant gas supply plate 31 made of carbon cloth can be used as a fuel cell separator.

In addition to these, the case where butyl rubber, butadiene rubber, and fluororubber were used as the gas impermeable resin around the carbon cloth of the gas supply plate (porous plate) was also examined, but similar results were obtained. .

[Embodiment 2] The conductive gas partition plate 21 has a length of 100 mm, a width of 100 mm, and a thickness of 1.0 mm.
100 mm in length x 100 mm in width for the fuel gas supply plate 11 and the oxidant gas supply plate 31.
B. Silicone rubber was molded with a width of 4 mm to 10 mm using a carbon cloth having a thickness of 0.5 mm and a porosity of about 70%.

Expanded graphite powder 70% and phenol resin 30%
Was mixed and hot-pressed at 220 ° C. and 10 MPa for 20 minutes to prepare the same. In each plate, a fuel gas supply hole 12 having a width of 3 mm and a length of 60 mm, a fuel gas discharge hole 13, and an oxidant gas supply hole 1 are located 5 mm from the four sides.
4. A through hole to be the oxidant gas discharge hole 15 was formed by a press punching method, and two sets of this were manufactured.

The obtained fuel gas supply plate 11, conductive gas partition plate 21 and oxidant gas supply plate 31 were assembled in the same manner as in Example 1 to produce a single cell. As the electrolyte membrane, a 30 μm-thick membrane manufactured by Japan GORE-TEX was used. Humidified hydrogen gas is supplied to the fuel electrode side, and humidified air is supplied to the air electrode side to obtain a hydrogen utilization rate of 70% and an air utilization rate of 40%.
%, 70 ° C. I / V characteristics were evaluated.

FIG. 4 is a graph showing the characteristics of a single cell using the above separator. In FIG. 4, for comparison, an artificial graphite plate having a thickness of about 5 mm and a width of 1 m according to the conventional technique is used.
The results of using a separator formed by mechanically cutting a gas channel having a depth of m × 1 mm at a pitch of 1 mm are also shown.

The single cell using the separator according to the present example is a comparative example 1 using the graphite separator according to the prior art.
The same current density / voltage characteristics were obtained as compared with the above. This shows that an inexpensive graphite mold plate can be used as the material of the conductive gas partition plate 21.

[Example 3] Using carbon cloth having a porosity of about 50 to 90%, a single cell having the same dimensions as in Example 1 was assembled by the same method, and a standard current density during operation of the polymer electrolyte fuel cell was obtained. The electromotive force and the pressure loss at 500 mA / cm ² were measured. FIG. 5 is a graph showing the characteristics of a single cell using the above separator.

The pressure loss decreases as the porosity increases, which is preferable, but the electromotive force also decreases. This is because the contact resistance increases as the porosity increases. Suitable pressure loss for operation of polymer electrolyte fuel cell
The porosity is about 60 to 80% in the range of 01 Mpa or less and the electromotive force of 550 mV or more at a current density of 500 mA / cm ² .
Is the range.

[Comparative Example 1] For comparison, a graphite separator was prepared using a conventional technique and the I / V characteristics of a single cell were measured.

A densified artificial graphite plate made of Nippon Graphite having a thickness of about 5 mm was cut into a size of 100 mm in length and 100 mm in width, and a gas passage of 1 mm in width and 1 mm in depth was cut by mechanical cutting at a pitch of 1 mm. It formed and produced the separator. Arrange these separators as shown in FIG. 6, sandwich both sides with a SUS plate 19 of 140 × 140 × 10 mm,
A single cell was produced by tightening. Membranes manufactured by Japan Gore-tex Co., Ltd. having thicknesses of 30 μm and 350 μm were used for the electrolyte membrane and the gas diffusion layer, respectively.

Humidified hydrogen gas was supplied to the fuel electrode side and humidified air was supplied to the air electrode side, and the I / V characteristics were evaluated under the conditions of 70% hydrogen utilization rate, 40% air utilization rate and 70 ° C. The results are shown in FIGS. 4 and 5 as Comparative Example 1.

Current density of 500 mA / cm ² and voltage of 0.63
The value of V was almost the same as that reported previously.

[0056]

EFFECTS OF THE INVENTION According to the present invention, a separator for a polymer electrolyte fuel cell can be provided with the same characteristics as the conventional one and at a cost about 40% lower than that of the conventional one.

[Brief description of drawings]

FIG. 1 is a top view of a separator in which a fuel gas supply plate, a conductive gas partition plate and an oxidant gas supply plate of the present invention are integrated via a conductive adhesive.

2 is a schematic cross-sectional view showing the structure of a polymer electrolyte fuel cell unit cell of Example 1. FIG.

3 is a graph showing characteristics of a single cell using the separator of Example 1. FIG.

FIG. 4 is a graph showing characteristics of a single cell using the separator of Example 2.

5 is a graph showing characteristics of a single cell using the separator of Example 3. FIG.

FIG. 6 is a schematic cross-sectional view showing an example of the structure of a solid polymer electrolyte fuel cell single cell using a conventional graphite separator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrolyte membrane, 2a ... Anode side separator, 2b ... Cathode side separator, 3a ... Anode (positive electrode), 3b ...
Cathode (negative electrode), 4a ... Anode gasket, 4b
... cathode-side gas gasket, 5a ... anode-side gas diffusion layer, 5b ... cathode-side gas diffusion layer, 6 ... fuel gas flow path,
7 ... Oxidant gas flow path, 11 ... Fuel gas supply plate, 12 ... Fuel gas supply hole, 13 ... Fuel gas discharge hole, 14 ... Oxidant gas supply hole, 15 ... Oxidant gas discharge hole, 16, 17 ... Conductivity Porous body, 18a, 18b, 18c, 18d ... Gas impermeable resin mold part, 19 ... SUS plate, 21 ... Conductive gas partition plate, 31 ... Oxidizing gas supply plate.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Yamauchi             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Norio Yamada             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Kazutoshi Higashiyama             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Yuichi Kamo             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. F-term (reference) 5H026 AA06 CC08 CX03 CX05 CX07                       EE02 EE05 EE18 HH04

Claims (8)

[Claims] 1. A solid polymer comprising a unit cell in which a positive electrode and a negative electrode are arranged on both sides of an electrolyte membrane, and a separator which sandwiches the unit cell and supplies a fuel gas to the positive electrode side and an oxidant gas to the negative electrode side. The separator of the fuel cell has a gas-impermeable conductive partition plate as a center, and a peripheral portion for supplying fuel gas to the positive electrode on one side of the partition plate is a gas-impermeable conductive porous plate. , A gas-impermeable conductive porous plate is arranged on the other side for supplying the oxidant gas to the negative electrode, and these three plates are integrated by a conductive adhesive. A polymer electrolyte fuel cell separator characterized by: 2. The solid polymer fuel cell separator according to claim 1, wherein the gas-impermeable conductive partition plate is a stainless steel plate coated with a corrosion-resistant conductive paint or a resin-molded carbon plate. 3. The separator for a polymer electrolyte fuel cell according to claim 1, wherein the conductive porous plate is a carbon cloth whose peripheral portion is molded with a resin having rubber elasticity. 4. The polymer electrolyte fuel cell separator according to claim 1, wherein the porosity of the conductive porous plate made of carbon cloth is 60 to 80%. 5. A solid polymer comprising a unit cell in which a positive electrode and a negative electrode are arranged on both sides of an electrolyte membrane, and a separator which sandwiches the unit cell and supplies a fuel gas to the positive electrode side and an oxidant gas to the negative electrode side. Type fuel cell, the separator has a gas-impermeable conductive partition plate as a center, and a peripheral portion for supplying fuel gas to the positive electrode on one side of the partition plate is a gas-impermeable conductive porous body. On the other side of the plate, a gas impermeable conductive porous plate is arranged on the other side for supplying the oxidant gas to the negative electrode, and these three plates are integrated by a conductive adhesive. Fuel cell characterized by being 6. The fuel cell according to claim 5, wherein the gas-impermeable conductive partition plate is a stainless steel plate coated with a corrosion-resistant conductive paint or a resin-molded carbon plate. 7. The fuel cell according to claim 5, wherein the conductive porous plate is a carbon cloth whose peripheral portion is molded with a resin having rubber elasticity. 8. The fuel cell according to claim 5, wherein the porosity of the conductive porous plate made of carbon cloth is 60 to 80%.