JP2001351643A - Separator for fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal separator for fuel cell that has excellent corrosion resistance. SOLUTION: The fuel cell separator is composed of a metal pate and comprises a contacting face with an electrode or the current collector and a reaction gas ventilating groove, and a polymer heat resistant film is formed on the surface of the reaction gas ventilating groove.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell separator, and more particularly to a separator that can be used in a vehicle-mounted fuel cell for powering an automobile.

[0002]

2. Description of the Related Art A fuel cell has been attracting attention as a next-generation power generator because it has a high energy conversion efficiency from fuel to electricity and does not emit harmful substances. In particular, polymer ion exchange membrane fuel cells that operate in a temperature range of 150 ° C. or less have been actively studied, and are expected to be put into practical use several years later.
This fuel cell can be operated at a relatively low temperature, has a high power generation output density, and can be downsized, so that it is suitable as a home or vehicle fuel cell.

In general, a polymer ion exchange membrane fuel cell is
A fuel cell and an oxygen electrode (air electrode) are fixed on both sides of the solid electrolyte membrane to form a unit cell (cell), and these are laminated via a plate-like separator provided with a ventilation groove for supplying fuel gas and air. It is constituted by. As the solid electrolyte membrane, a fluororesin-based ion exchange membrane having a sulfonic acid group or the like is used, and the electrode is formed of carbon black in which a water-repellent material PTFE and a noble metal fine particle catalyst are dispersed. When the hydrogen-oxygen fuel cell operates, protons generated by oxidizing hydrogen gas enter the electrolyte and combine with water molecules.
It becomes H ₃ O ⁺ and moves to the positive electrode side. On the positive electrode side, oxygen introduced from the ventilation groove obtains electrons generated by the oxidation reaction of hydrogen and combines with protons in the electrolyte to form water. By continuing these reaction processes, electric energy can be continuously taken out. The theoretical electromotive force of this cell is 1.
Although it is 2V, the output is actually caused by electrode polarization, crossover of reaction gas (phenomenon of fuel gas passing through the electrolyte and leaking to the air electrode), voltage drop due to contact resistance between electrode and current collector, etc. The voltage is about 0.6-0.8V. Therefore, in order to obtain a practical output, it is necessary to stack dozens of cells via a separator and connect them in series.

As can be understood from the above-described power generation principle, a large amount of H ⁺ is present in the electrolyte, so that the electrolyte becomes strongly acidic inside the electrolyte where a large amount of water or water vapor is present and near the electrodes. In addition, oxygen is combined with H ⁺ on the positive electrode side to generate water, but hydrogen peroxide may be generated depending on the operation state of the battery. Since the separator is incorporated in such an environment, it is required to have high chemical / electrochemical stability (corrosion resistance) in addition to electric conductivity and airtightness.

Many conventional fuel cell separators are obtained by machining a graphite plate. Graphite separators have low electrical resistance and high corrosion resistance, but have low mechanical strength and high processing costs. Since it is required that a separator used for an in-vehicle fuel cell has high mechanical strength and can be processed at low cost, it is difficult to apply a current graphite separator to an in-vehicle fuel cell as it is. In recent years, a method of manufacturing a separator by mixing graphite powder with a resin, injection molding and firing at a high temperature has been studied, but there is a problem that the density of the obtained fired body is low and airtightness is poor.
It is possible to increase the density by immersing this separator in a resin and carbonizing and refiring, but the manufacturing process becomes complicated. In addition, the contact electric resistance of the separator thus manufactured is several times higher than that of the conventional graphite separator, and a decrease in the output voltage of the battery is inevitable.

[0006] In addition to the graphite separator, a separator made of metal has been studied. Metal separators have low bulk electrical resistance, high airtightness and mechanical strength, and are easy to reduce processing costs. In addition, since the thickness of the separator can be reduced, miniaturization is easy. Further, when a low specific gravity metal material such as aluminum is used, the weight of the fuel cell can be further reduced. However, the metal separator has a problem that the metal itself of the base material is easily corroded. In particular, it has been reported that aluminum substrates have a very high corrosion rate (RL Rorup, et al., Mate
r. Res. Soc. Symp. Proc., 393 (1995)). Also, when metal ions generated by corrosion enter the electrolyte membrane,
The ionic conductivity of the membrane may be reduced and affect the performance of the battery.

JP-A-11-162478 discloses a method of improving corrosion resistance by plating a noble metal on the entire surface of a metal separator. Although this method has no problem with respect to the separator performance, it is not practical because it increases the cost. In order to reduce costs, it is necessary to reduce the thickness of the noble metal plating layer. However, if the thickness is reduced during wet plating, fine pinholes are generated and cause corrosion, and dry plating (evaporation, sputtering, etc.) produces The efficiency is poor, and the uniformity of the coating is also deteriorated.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a metal fuel cell separator having excellent corrosion resistance.

[0009]

Means for Solving the Problems As a result of intensive studies in view of the above problems, the present inventors have found that a metal fuel cell separator partially provided with a polymer heat-resistant coating exhibits excellent corrosion resistance. Then, the present invention has been made.

That is, the fuel cell separator of the present invention is made of a metal plate, has a contact surface with an electrode or a current collector, and a reaction gas ventilation groove, and a polymer heat-resistant coating is formed on the surface of the reaction gas ventilation groove. It is characterized by being formed.

The above-mentioned polymer heat-resistant coating preferably has water repellency, and is preferably a vinyl resin, polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, aromatic polyamide, polyimide, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, or polyester. , Polystyrene or its derivatives, copolymers of styrene and other monomers, polyethylene, polypropylene, polyurethane, silicone resin, polysulfone,
It is preferably made of polyethersulfone, rayon, cupra, acetate resin, promix, vinylon, vinylidene resin and / or acryl. Further, the polymer heat-resistant coating preferably has a multilayer structure composed of two or more layers.

The metal plate used as the substrate is preferably made of aluminum or an aluminum alloy. in this case,
In order to further improve the corrosion resistance of the separator, it is preferable to form an alumite coating on the surface of the above-described reaction gas ventilation groove, and to form a polymer heat-resistant coating on the alumite coating.
The purity of aluminum or aluminum alloy is preferably 99.5% or more.

The alumite coating is preferably a porous alumite coating having a porosity of 5% or more. It is also preferable that the alumite coating is composed of a dense alumite coating having a porosity of less than 5% and a porous alumite coating having a porosity of 5% or more formed thereon.

Preferably, a conductive film is formed on the contact surface with the electrode or the current collector. Conductive film is Pt, Au, Pd, R
It is preferably made of a metal selected from the group consisting of u, Rh, Ir and Ag, or an alloy thereof, carbon, or a conductive carbide.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The fuel cell separator of the present invention is made of a metal plate and has a contact surface with an electrode or a current collector and a reactive gas vent groove. A polymer heat-resistant coating is formed on the surface of the reaction gas ventilation groove. INDUSTRIAL APPLICABILITY The separator of the present invention can be used for various fuel cells, and can be particularly suitably used for an in-vehicle fuel cell for driving an automobile.

The metal plate used as the separator substrate preferably has a dense structure. Here, "dense" means that the reaction gas does not permeate the metal plate and does not cause crossover because there is substantially no through hole or the like. It is preferable to use a separator substrate made of a metal having high electric conductivity and earthquake resistance. In addition, when used as an in-vehicle fuel cell for automobiles, it is necessary to reduce the weight of the separator. Therefore, it is preferable to use a light metal such as aluminum, titanium, or magnesium or an alloy thereof as a base material, and to use aluminum or an aluminum alloy. More preferred. The thickness of the substrate is not particularly limited,
When it is used for an in-vehicle fuel cell, the thickness is preferably 0.5 to 3 mm. When any metal is used as the base material, the shape and production method of the separator in the present invention, the material and the formation method of the polymer heat-resistant coating are basically the same.
The fuel cell separator according to the present invention when an aluminum metal plate is used as a substrate will be described with reference to the drawings.
The present invention is not limited thereto, and various changes can be made without changing the gist of the present invention.

FIG. 1 is a partial schematic view showing an example of a fuel cell including a fuel cell separator according to one embodiment of the present invention. The fuel cell shown in FIG. 1 includes a unit cell 1 composed of a solid electrolyte 2 and anodes 3 and cathodes 4 provided on both sides thereof.
It is configured by laminating via a separator 5. Both ends of the stack are connected to an external circuit (not shown).

As shown in FIG. 1, the separator 5 of the present invention
Have reaction gas vent grooves 9 and 10. Usually, a fuel gas is supplied to a passage formed by the reaction gas ventilation groove 10 and the anode 3, and an oxidizing gas is supplied to a passage formed by the reaction gas ventilation groove 9 and the cathode 4. The reaction gas ventilation grooves 9 and 10 may be formed in a predetermined pattern by a method such as machining, pressing, precision casting, chemical polishing (etching), and electrolytic polishing. Although the shape of the reaction gas ventilation groove is U-shaped in FIG. 1, the shape is not particularly limited as long as a reaction gas passage can be formed in a portion in contact with the electrode, and the reaction gas ventilation resistance is small and the power generation efficiency is high. It is preferable to set so that Normally, the depth of each reaction gas ventilation groove is 0.2 to 2 m
m and the width is preferably 0.5 to 5 mm.

In order to ensure the corrosion resistance of the metal separator, a polymer heat-resistant coating 6 is formed on the surfaces of the reaction gas ventilation grooves 9 and 10 which do not come into contact with electrodes or the like (see FIG. 1). The polymer heat-resistant coating preferably has a dense structure. Here, the “dense structure” means a structure through which a gas such as water or water vapor does not permeate.

The polymer heat-resistant coating preferably has water repellency. When it has water repellency, there is no stagnation of water, so that corrosion of the base material is suppressed and the corrosion resistance of the separator can be greatly improved. In the present invention, "having water repellency" means that there is no adhesion or stagnation of water, for example, the contact angle when the liquid is brought into contact with the solid-gas interface of the coating and replaced with the solid-liquid interface is 90 ° It is the above. Further, since the operating temperature of the fuel cell is usually 80 to 120 ° C., the softening point of the material used for the polymer heat-resistant coating is 120 ° C. in consideration of long-term stability.
It is preferable that this is the case.

The polymer material forming the polymer heat-resistant film includes vinyl resins such as polyvinyl butyral (PVB), polyvinyl chloride (PVC), and polytetrafluoroethylene (P
TFE), polyvinylidene fluoride, aromatic polyamide, polyimide, polycarbonate, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyester, polystyrene or its derivatives, copolymers of styrene with other monomers, polyethylene, polypropylene, It is preferable to use polyurethane, silicone resin, polysulfone, polyethersulfone, rayon, cupra, acetate resin, promix, vinylon, vinylidene resin and / or acryl.

The polymer heat-resistant coating preferably has a multilayer structure composed of two or more layers. For example, as shown in FIG. 2, the polymer heat-resistant coating is formed of two types of polymer heat-resistant coatings 6,
It may be a two-layer structure composed of 6 ′. In this case, the polymer heat-resistant coating 6 is formed of a polymer material having excellent adhesion to a metal substrate, and the polymer heat-resistant coating 6 ′ is formed of a polymer material having excellent waterproofness. Particularly preferred from the viewpoint of improvement.

The method for forming the polymer heat-resistant coating is not particularly limited. For example, the polymer may be formed by dissolving the above polymer material in an appropriate organic solvent, dipping the separator in the obtained solution, and then drying. Alternatively, the separator may be formed by coating the separator with a thin polymer film and fusing it by heating.

In order to further improve the corrosion resistance, it is preferable to appropriately treat the surface of the reaction gas ventilation groove. As shown in FIG. 3, when a metal plate made of aluminum or an aluminum alloy is used as the base material, the reaction gas vent grooves 9 and 10 are used.
Chemically and physically stable alumite coating on inner surface 7
Is preferably formed, and the polymer heat-resistant coating 6 is formed thereon. It is considered that the cause of the deterioration of the corrosion resistance of the separator having the alumite film formed thereon is cracking or peeling that occurs when the alumite film swells and grows in water vapor to cause film distortion. In particular, in the case of a fuel cell mounted on an automobile, the alumite film is placed in an environment where the temperature and the humidity change greatly, so that film distortion is likely to occur. In the present invention, since the waterproof polymer heat-resistant coating is formed on the alumite coating, the deterioration of the alumite coating due to such water vapor can be suppressed.

The alumite film can be formed by an anodic oxidation method or the like. For example, the γ-alumina coating may be formed on the surface of the substrate by performing electrolysis using an aqueous solution of oxalic acid, sulfuric acid, chromic acid, or the like as an electrolytic solution. From the viewpoint of corrosion resistance, the thickness of the alumite coating is preferably from 5 to 50 μm, more preferably from 10 to 30 μm.

By appropriately adjusting the anodic oxidation conditions,
A dense hard alumite coating can be formed, and the corrosion resistance is further improved. Further, after the anodic oxidation treatment, the treatment with boiling water or steam can close the fine pores specific to the alumite coating.

By appropriately selecting the electrolysis conditions for anodic oxidation, fine vertical pores and spongy porous layers can be formed in the alumite coating. As shown in FIG. 3, the adhesiveness of the polymer film 6 can be improved by using the porous alumite film 11 as the alumite film 7. The porosity of the porous alumite coating is preferably 5
%, More preferably 10% or more.

As shown in FIG. 4, when the alumite coating 7 is composed of a dense alumite coating 12 having a porosity of less than 5% and a porous alumite coating 11 having a porosity of 5% or more formed thereon, the above-mentioned improvement in corrosion resistance is achieved. The effect and the effect of improving the adhesion are simultaneously obtained, which is preferable. In such a case, it is particularly preferable that the porosity of the porous alumite coating be 20% or more. The thickness of the dense alumite coating is preferably 2 to 30 μm, and the thickness of the porous alumite coating is 5 to 30 μm.
Preferably it is 50 μm.

If the aluminum or aluminum alloy used as the base material contains a large amount of impurities, the uniformity of the alumite film deteriorates and the density decreases. Further, in such a case, once the alumite coating is formed, the effect of the densification treatment using boiling water, steam, or the like is reduced. Therefore, the purity of the aluminum or aluminum alloy used for the separator of the present invention is preferably 99.5% or more, and more preferably 99.9% or more.

The separator of the present invention has a contact surface with an electrode or a current collector. The shape of the contact surface may be any shape suitable for contacting the electrode of the fuel cell or the carbon paper or carbon cloth of the primary current collector, and is not limited by the drawings.

As shown in FIGS. 1 to 4, a conductive film 8 is preferably formed on a contact surface (electrically conductive surface) with an electrode or a current collector. In the separator of the present invention, it is preferable to cover the entire surface with a polymer heat-resistant coating and a conductive coating. That is, only the portion that is in contact with the electrode and conducts electricity is coated with a noble metal having good electrical conductivity, and a chemically or physically stable polymer heat resistant coating is formed on the surface in the ventilation groove,
It is preferable to make the corrosion resistance and electric conductivity of the base material compatible.

The conductive film is preferably formed using a material having good electrical conductivity and corrosion resistance, and Pt, Au, Pd,
More preferably, it is formed of a metal selected from the group consisting of Ru, Rh, Ir, and Ag or an alloy thereof, carbon, or a conductive carbide. Noble metal-based coatings such as Au, Ag, Pt, and Pd have low contact resistance and extremely good corrosion resistance. As the carbon, a graphite film by CVD, a DLC film (diamond-like carbon film) and the like are preferable. Further, graphite powder to which a water repellent is added may be applied. When the electrode is made of carbon black to which a small amount of Pt is added, the use of a carbon coating provides good contact familiarity. As the conductive carbide, silicon carbide, niobium carbide, tungsten carbide and the like are preferable. The carbide coating not only has low contact resistance, but also has good corrosion resistance and oxidation resistance, and thus acts as a protective film for the separator.

The conductive film can be formed by a method such as sputtering, electroplating, wet plating, and CVD. The thickness of the conductive film is preferably 0.01 to 5 μm. Film thickness
If less than 0.01 μm, the film strength is weak and unstable, and 5 μm
If it is larger, the cost increases, which is not preferable.

[0034]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

Example 1 Each separator base material shown in Table 1 (1 mm × 150 mm × 150 mm)
Then, a reaction gas ventilation groove having a depth of 1.0 mm and a width of 3.0 mm was formed by pressing. 15 parts by weight of polyvinyl butyral (PVB) in 100 parts by weight of butyl acetate
After dipping in a solution of powder, about 150
Cure treatment was performed at ℃ to form a polymer heat-resistant coating on the entire surface. Next, in order to improve the flatness of the electrode contact surface of each separator, the electrode contact surface was lapped and polished and washed. By this step, the polymer heat-resistant coating made of PVB formed on the electrode contact surface was removed. Next, 5mTorr
In a pure argon gas atmosphere, the substrate temperature was set to 200 ° C., and Au was sputtered on the electrode contact surface to form a conductive film, thereby producing separators according to the present invention. The thickness of the Au conductive film was about 1 μm.

To 100 parts by weight of carbon black, 15 parts by weight of Pt paste (Pt: 90% by weight) was added, and further 15 parts by weight of Teflon (registered trademark) particles (average particle size: 0.2 μm) were added to a water repellent. To prepare a paste for an electrode. This electrode paste is mixed with a proton-conductive polymer solid electrolyte membrane (Na
fion) and dried. This was sandwiched between carbon cloths, and further sandwiched between the two separators described above.
Fuel cells (unit cells) 1a to 1d were manufactured. The tightening pressure of the separator was 10 kg / cm ² .

Fuel cells 1a 'to 1d' for comparison were produced in the same manner as in the production of fuel cells 1a to 1d, except that the polymer heat-resistant coating was not formed. Further, a comparative fuel cell 1e 'having no polymer heat-resistant coating was produced in the same manner as the fuel cells 1a to 1d, using graphite as a separator base material.

The simulated fuel gas (70% H ₂ , humidified in the reaction gas vent groove on the anode side) was supplied to the obtained fuel cells 1 a to 1 d of Example 1 and the comparative fuel cells 1 a ′ to 1 e ′. 15% C
O ₂ , 15% H ₂ O) was supplied, and air was supplied as an oxidizing agent to the cathode side ventilation groove to evaluate the power generation performance stability. The evaluation was performed for 13 days. Table 1 also shows the separator substrate of each fuel cell, the polymer material used for the polymer heat-resistant coating, the initial power generation voltage, the power generation voltage after 13 days of operation, and the corrosion resistance of the separator after 13 days of operation. .

[0039]

[Table 1]

From Table 1, it can be seen that the separator of the present invention provided with the polymer heat-resistant coating exhibits excellent corrosion resistance, and that the fuel cells 1a to 1d of Example 1 using the separator exhibit high power generation performance stability. Understand.

[0041] Example 2 as a material of the conductive film in the same manner as the method for manufacturing the fuel cell 1a except for using the materials shown in Table 2, the fuel cell of Example 2 including the separator of the present invention 2a~2r Were prepared respectively. In addition, a comparative fuel cell having no conductive coating
2 'was similarly prepared. However, when forming a conductive film of carbon (2q) and conductive carbide SiC (2r), use a target of the film composition and use Ar (30 mT
orr) was used. The obtained fuel cells 2a to 2r of the second embodiment,
Simulated fuel gas (70% H ₂ , 20% CO ₂ , 10% H ₂ O) humidified in the reaction gas vent groove on the anode side with respect to the comparative fuel cell 2 ′ and the comparative fuel cell 1e ′ Was supplied, and air was supplied as an oxidizing agent to the cathode side ventilation groove to evaluate the power generation performance stability. The evaluation was performed for 12 days. Conductive coating material,
Table 2 also shows the initial power generation voltage, the power generation voltage after 12 days of operation, and the corrosion resistance of the separator after 12 days of operation.

[0042]

[Table 2]

From Table 2, it can be seen that the aluminum separator according to the present invention having the above-described preferred conductive coating exhibits excellent corrosion resistance, and the fuel cells 2a to 2r of Example 2 using the separator exhibit high power generation performance stability. You can see that.

Example 3 The fuel cell 1a had the same structure as the fuel cell 1a except that an alumite coating having the porosity shown in Table 3 was formed on the surface of the reaction gas ventilation groove of the aluminum substrate, and a polymer heat-resistant coating was formed thereon. Similarly to the manufacturing method, fuel cells 3a to 3i of Example 3 including the separator of the present invention were manufactured. The alumite film was formed by performing anodization in an oxalic acid aqueous solution, then immersing the film in boiling water for 30 minutes, and then drying. The thickness of the alumite coating was 15 μm. Also, fuel cells 3a 'to 3i' for comparison were prepared in the same manner as in the case of the fuel cells 3a to 3i except that the polymer heat-resistant coating was not formed. The obtained fuel cells 3a to 3i of Example 3 and comparative fuel cells 3a 'to 3i'
Was evaluated for power generation performance stability in the same manner as in Example 2 above. However, the evaluation was performed for 48 days. Porosity of the alumite film of each fuel cell, initial generation voltage, generation voltage after 48 days of operation,
Table 3 also shows the peeling state of the alumite film after the operation for 48 days.

[0045]

[Table 3]

As can be seen from Table 3, when the separator of the present invention has an alumite coating, its porosity is preferably at least 4.82%, more preferably at least 9.84%. Further, it was confirmed that the separator of the present invention can suppress peeling of the alumite film by forming the polymer heat-resistant film as compared with the separator used for the fuel cells 3a 'to 3i'.

[0047] Similar to the method for manufacturing the fuel cell 1a except for using the materials shown in Table 4 as the polymer material for forming the embodiment 4 polymeric heat-resistant coating, Example 4 containing the separator of the present invention Were manufactured, respectively. However, the method for forming the polymer heat-resistant film was appropriately selected from a solution coating method and a heat fusion method depending on the polymer material used. The power generation performance stability of the obtained fuel cells 4a to 4w of Example 4 was evaluated in the same manner as in Example 2. Polymer material of each fuel cell, initial generation voltage, 12
Table 4 shows the generated voltage after the operation for one day and the corrosion resistance after the operation for 12 days.

[0048]

[Table 4]

From Table 4, it can be seen that all of the separators of the present invention having the above-mentioned preferred polymer heat-resistant coating exhibit excellent corrosion resistance, and that the fuel cell 4a of Example 4 using the separator was used.
It can be seen that ~ 4w shows high power generation performance stability.

[0050]

As described in detail above, since the fuel cell separator of the present invention uses a metal plate as a base material, it is much lighter than conventional graphite separators, has high mass productivity, and can reduce processing costs. . In addition, in the present invention, a separator having excellent corrosion resistance can be obtained by forming a polymer heat-resistant coating on the surface of the reaction gas ventilation groove. The fuel cell using the separator of the present invention has high power generation performance stability.

[Brief description of the drawings]

FIG. 1 is a partial schematic view showing an example of a fuel cell including a fuel cell separator according to one embodiment of the present invention.

FIG. 2 is a schematic view showing a fuel cell separator according to another embodiment of the present invention, and a partially enlarged view showing the structure of a polymer heat-resistant coating thereof.

FIG. 3 is a schematic view showing a fuel cell separator according to another embodiment of the present invention, and a partially enlarged view showing the structure of a polymer heat-resistant coating and an alumite coating thereof.

FIG. 4 is a schematic view showing a fuel cell separator according to another embodiment of the present invention, and a partially enlarged view showing the structure of a polymer heat-resistant coating and an alumite coating thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Single cell 2 ... Solid electrolyte 3 ... Anode 4 ... Cathode 5 ... Separator 6, 6 '... Polymer heat-resistant coating 7 ... Alumite coating 8 ... Conduction Porous coating 9,10 ・ ・ ・ Reaction gas vent groove 11 ・ ・ ・ Porous alumite coating 12 ・ ・ ・ Dense alumite coating

Claims (11)

[Claims] 1. A fuel cell separator made of a metal plate and having a contact surface with an electrode or a current collector and a reactive gas ventilation groove, wherein a polymer heat-resistant coating is formed on the surface of the reaction gas ventilation groove. A fuel cell separator characterized by the above-mentioned. 2. The fuel cell separator according to claim 1, wherein the polymer heat-resistant coating has water repellency. 3. The fuel cell separator according to claim 1, wherein the polymer heat-resistant coating is a vinyl resin,
Polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, aromatic polyamide, polyimide, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyester, polystyrene or derivatives thereof, copolymers of styrene and other monomers, polyethylene, polypropylene, Polyurethane, silicone resin, polysulfone, polyethersulfone,
Rayon, cupra, acetate resin, promix,
A fuel cell separator comprising vinylon, vinylidene resin and / or acryl. 4. The fuel cell separator according to claim 1, wherein the polymer heat-resistant coating has a multilayer structure composed of two or more layers. 5. The fuel cell separator according to claim 1, wherein the metal plate is made of aluminum or an aluminum alloy. 6. The fuel cell separator according to claim 5, wherein the polymer heat-resistant coating is formed on an alumite coating provided on a surface of the reaction gas ventilation groove. For separator. 7. The fuel cell separator according to claim 6, wherein the alumite coating is a porous alumite coating having a porosity of 5% or more. 8. The fuel cell separator according to claim 6, wherein the alumite coating is a dense alumite coating having a porosity of less than 5% and a porosity of 5% formed thereon.
A fuel cell separator comprising the porous alumite coating described above. 9. The fuel cell separator according to claim 5, wherein the purity of the aluminum or aluminum alloy is 99.5% or more. 10. The fuel cell separator according to claim 1, wherein a conductive film is formed on a contact surface with the electrode or the current collector. . 11. The fuel cell separator according to claim 10, wherein the conductive film is a metal selected from the group consisting of Pt, Au, Pd, Ru, Rh, Ir, and Ag, or an alloy thereof, carbon, or a conductive material. A fuel cell separator comprising a conductive carbide.