KR20060055291A - Solid polymer electrolyte membrane, manufacturing method thereof and fuel cell using the same - Google Patents

Abstract

The present invention provides a solid polymer electrolyte membrane, a method of manufacturing the same, and a fuel cell using the same, which exhibits a long-term stable performance under operating conditions of 100% to 300 ° C and operating conditions of no humidification or relative humidity of 50% or less. The polymer electrolyte membrane includes a polymer compound having a side chain containing a structural unit (a) represented by the following formula (a) at a nitrogen-containing heterocyclic nitrogen atom site constituting polybenzimidazoles.

[Formula 1]

Description

Solid polymer electrolyte membrane, manufacturing method and fuel cell using the same

 1 is a graph showing the relationship between the current density in the initial state and the battery voltage for Example 1 and Comparative Example 1,

2 is a graph showing the relationship between the battery voltage during power generation at the open circuit voltage and the current density of 0.3 A / cm ² and the operating time of the fuel cell for Example 1 and Comparative Example 1. FIG.

The present invention relates to a solid polymer electrolyte membrane, a manufacturing method thereof and a fuel cell using the same.

Background Art Conventionally, ion conductors in which ions move by applying a voltage are known. This ion conductor is widely used as an electrochemical device, such as a battery and an electrochemical sensor.

For example, in fuel cells, in terms of power generation efficiency, system efficiency, and long-term durability of a component, good proton conductivity can be obtained in a low-humidity operating condition of 100% to 300 ° C at an operating temperature of 100 to 300 ° C. There is a demand for a stable proton conductor.

In the development of a conventional polymer electrolyte fuel cell, it has been considered in view of the above requirements. In a solid polymer fuel cell using a perfluorocarbon sulfonic acid membrane as an electrolyte membrane, the relative humidity is 50% or less at an operating temperature of 100 to 300 ° C. In this case, there is a disadvantage in that sufficient power generation performance cannot be obtained.

In addition, a fuel cell using an electrolyte membrane containing a conventional proton conductivity imparting agent (for example, Japanese Patent Application Laid-Open No. 2001-035509), a fuel cell using a silica dispersion film (for example, Japanese Patent Application Laid-Open No. 06-111827), inorganic Fuel cells using organic composite membranes (e.g., Japanese Patent Application Laid-Open No. 2000-090946), fuel cells using phosphate dope graft membranes (e.g., Japanese Patent Publication No. 2001-213978), or fuels using ionic liquid composite membranes Batteries (for example, Japanese Patent Laid-Open Nos. 2001-167629 and 2003-123791).

In addition, US Patent No. 5,525,436 discloses a solid polymer electrolyte membrane made of polybenzimidazole doped with a strong acid such as phosphoric acid.

However, in the techniques described in Japanese Patent Laid-Open Nos. 2001-035509, 2000-090946, 2001-213978, and Japanese Patent Laid-Open No. 06-111827, there is a problem in that power generation performance can not be stably exhibited for a long time. In particular, long-term stability under operating environments of 100 to 300 ° C., no humidification or relative humidity of 50% or less is not sufficient.

In addition, in the phosphoric acid fuel cell, the solid oxide fuel cell, and the molten salt fuel cell, since the operating temperature is much higher than 300 ° C., the requirements are not sufficiently met in terms of cost, such as a problem in the long-term stability of the constituent members.

On the other hand, according to the technique described in US Pat. No. 5,525,436, it is possible to obtain a solid polymer fuel cell that exhibits relatively good power generation performance even at a high temperature up to 200 ^° C.

However, in the technique described in US Pat. No. 5,525,436, power generation at a relatively high temperature is possible, but it is difficult to maintain power generation performance stably even for this solid polymer fuel cell.

Thus, in view of the generation efficiency of the fuel cell, the system efficiency, and the long-term durability of the constituent members, the generation performance under low-humidity operation conditions with no humidification or a relative humidity of 50% or less at an operating temperature of 100 to 300 ° C is long term. There is a demand for a stable fuel cell, which is difficult in the prior art and has not yet achieved sufficient performance.

The present invention has been made to solve the above problems, a solid polymer electrolyte membrane exhibiting long-term stable performance under operating conditions of 100% to 300 ° C, operating conditions of no humidification or relative humidity of 50% or less, a method for producing the same, and It is an object to provide a fuel cell using the same.

In order to achieve the above object, the present invention adopts the following configuration.

The solid polymer electrolyte membrane of the present invention comprises a polymer compound having a side chain containing a structural unit (a) represented by the following formula (a) at a nitrogen-containing heterocyclic nitrogen atom site constituting polybenzimidazoles It features.

[Formula 1]

In addition, a structural unit shall represent the monomeric unit which comprises a polymer (polymer).

In addition, the manufacturing method of the solid polymer electrolyte membrane of the present invention, after doping the vinyl phosphonic acid to the polymer compound having a substituent having a carbon-carbon double bond bonded to the nitrogen-containing heterocyclic nitrogen atoms constituting the polybenzimidazoles, It characterized by having a step of producing a polymer compound in which the vinyl phosphonic acid is polymerized by the carbon-carbon double bond by performing the polymerization.

In addition, the fuel cell of the present invention, the carbon electrode; Fuel electrode; In a fuel cell comprising a unitary cell comprising a solid polymer electrolyte membrane sandwiched between the carbon electrode and the fuel electrode, an oxidant bipolar plate having an oxidant flow path formed on the carbon electrode side, and a fuel flow path plate having the fuel flow path formed on the fuel electrode side. The solid polymer electrolyte membrane is characterized in that the solid polymer electrolyte membrane of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail.

Solid polymer electrolyte membrane and its manufacturing method

The solid polymer electrolyte membrane of the present invention contains a polymer compound having a side chain containing the structural unit (a) represented by the formula (a) at a nitrogen-containing heterocyclic nitrogen atom site constituting polybenzimidazoles. Although the ratio of the said high molecular compound in a solid polymer electrolyte membrane is not specifically limited, Preferably it is 80 weight% or more, More preferably, it is 90 weight% or more, Most preferably, it is 100 weight%. In addition, although the said high molecular compound may contain a small amount of unreacted materials used at a manufacturing process, such as vinyl phosphonic acid, it can use without a problem also in this case.

In addition, the said side chain should just have one or more structural unit (a). The upper limit of the number of structural units (a) per one side chain is not particularly limited, but is 20 or less. When the structural unit (a) is at the end of the side chain, hydrogen atoms are bonded at the end of the side chain.

The preferable aspect, such as the introduction amount of a structural unit (a), is mentioned later.

In addition, the method for producing a solid polymer electrolyte membrane of the present invention preferably has the following steps.

(1) Nitrogen complex constituting polybenzimidazoles by introducing a substituent having a carbon-carbon double bond to a nitrogen-containing heterocyclic nitrogen atom constituting polybenzimidazoles (hereinafter also referred to as "polymer 1"). A high molecular compound (hereinafter referred to as "polymer 2") having a cyclic nitrogen atom bonded to a substituent having a carbon-carbon double bond is obtained.

(2) A structural unit represented by the above formula (a) by polymerizing vinyl phosphonic acid to the carbon-carbon double bond by performing addition polymerization after doping (adding) vinyl phosphonic acid to polymer 2 The polymer compound (henceforth "polymer 3") which has the side chain containing () in the nitrogen-containing heterocyclic nitrogen atom site which comprises polybenzimidazoles is obtained.

Hereinafter, embodiment of a solid polymer electrolyte membrane is also demonstrated by demonstrating according to the procedure of the manufacturing method of a solid polymer electrolyte membrane.

First, the polymer 1 will be described.

Polymer 1 may be a polymer exemplified in the following formulas (b-1)-(b-3) or a derivative thereof.

[Formula 2]

These polymers are excellent in heat resistance and can contain a lot of acid, and are preferable as a component of a solid polymer electrolyte membrane for a fuel cell.

In addition, in the said General formula (b-1)-(b-3), n is 10-100,000.

If n is 10 or more, mechanical strength is enough, and if n is 100,000 or less, solubility in an organic solvent etc. is favorable and it is suitable for manufacture of a solid polymer electrolyte membrane. If n is less than 10, it is not preferable to make the electrolyte membrane difficult.

These polymers can be manufactured by a well-known technique. For example, the polymer is preferably prepared according to the manufacturing method described in US Pat. No. 3,313,783, US Pat. No. 3,509,108, US Pat. No. 3,555,389 and the like.

The polymer 1 may be used alone or in combination of two or more thereof.

Next, the polymer 2 will be described.

Polymer 2 is a polymer compound in which a substituent having a carbon-carbon double bond is bonded to a nitrogen-containing heterocyclic nitrogen atom constituting Polymer 1.

The polymer 2 can be obtained by introducing the substituents into the polymer 1.

As the polymer 2, for example, in a structural unit represented by the above formulas (b-1)-(b-3), a nitrogen-containing heterocyclic active hydrogen (hydrogen atom bonded to nitrogen) is ringed with the substituent to provide the substituent. The one which has the structure which introduce | transduced is mentioned.

For example, when polybenzimidazoles (polymer 1) composed of the structural units represented by the above formula (b-1) are used, they have a structure represented by the following formula (c).

[Formula 3]

In the above formula, R ₁ and R ₂ are each independently a substituent having a carbon-carbon double bond or a hydrogen atom, and at least one of R ₁ and R ₂ is selected from the above substituents.

R _1, R ₂ is a carbon-a substituent or a hydrogen atom with a carbon-carbon double bond, at least one of R _1, R ₂ is more preferably a may be selected from the above-mentioned substituents, among others R _1, R ₂ both have the substituent desirable.

Although the number of carbon-carbon double bonds in a substituent is not specifically limited, It is preferable that it is one. In addition, the position of a carbon-carbon double bond in a substituent is not specifically limited, It is preferable to exist in the terminal.

In addition, the substituent should just have a carbon-carbon double bond, and the structure other than that is not specifically limited, A preferable substituent is a chain shape which does not contain a cyclic group (even if it is a straight chain | strand may be branched). More preferable examples of the substituent include an ether bond and a hydrocarbon group in which a carbonyl group may be inserted between the carbon-carbon bonds.

The polymer 2 is, for example, a molecule having an isocyanate group or glycidyl group and a carbon-carbon double bond in the molecule with the polymer 1 (hereinafter referred to as "molecule which introduces a substituent group"), as represented by the following Schemes 1 and 2 It can be obtained by reaction with).

[Formula 4]

In the above formula, R ₃ is a divalent organic group, and R ₄ is a hydrogen atom or a monovalent organic group.

[Formula 5]

In the above formula, R ₅ is a divalent organic group, and R ₆ is a hydrogen atom or a monovalent organic group.

As a molecule which introduce | transduces the said substituent, the essential functional group should just exist in a molecule | numerator, and there is no restriction | limiting in particular about other molecular structure.

For example, in the molecule | numerator which introduce | transduces the substituent group used by reaction formula (1), it is preferable that R <_3> is a divalent organic group and is linear or branched chain type. As R ₃ , more preferably, a hydrocarbon group in which an ether bond or a carbonyl group may be inserted between the carbon-carbon bonds is mentioned. This hydrocarbon group is preferably saturated. Moreover, preferable carbon number of this hydrocarbon group is 1-5, for example.

Moreover, R <_4> is a hydrogen atom or monovalent organic group, As an organic group, an alkyl group is preferable and its carbon number is 1-3 preferably.

In the molecule | numerator which introduce | transduces the substituent used by Scheme 2, R <_5> is the same as R <_3>, and R <_6> is the same as R <_4> .

As a molecule for introducing a substituent, more preferably 2-isocyanatoethyl methacrylate represented by the following general formula (c-1) or the general formula (c) in consideration of the reactivity with the polybenzimidazoles, durability and the like. It is preferable to use one or more selected from 2-isocyanatoethyl acrylate represented by -2) and glycidyl methacrylate represented by the formula (c-3).

[Formula 6]

[Formula 7]

[Formula 8]

The reaction between the polymer 1 and the molecule introducing the substituent may be performed by any process in the process of preparing the polymer 2 from the polymer 1 to obtain a solid polymer electrolyte of the present invention.

For example, in the step of removing the solvent from the solution of the polymer 1 by heating to form a film, a molecule in which a substituent is introduced into the molecule in advance is dissolved in the solution of the polymer 1, and at the same time the solvent is removed by heating. Since the reaction method shown by said reaction formula (1) and the manufacturing method which advances the reaction represented by said reaction formula (2) are efficient, it is preferable.

Although there is no limitation in the ratio of substituting the nitrogen-containing heterocyclic activated carbon constituting the polymer 1 with the substituent, 20% or more, preferably 50% or more, of the total nitrogen-containing heterocyclic activated hydrogen constituting the polymer 1 is substantially It is preferable to substitute 100% or less.

The ratio to substitute is calculated | required from the quantity used for reaction since the reaction represented by the above-mentioned reaction formula (1) or reaction formula (2) advances equivalently, for example.

Next, the polymer 3 will be described.

The polymer 3 is a polymer compound having a side chain containing the structural unit (a) represented by the formula (a) at a nitrogen-containing heterocyclic nitrogen atom constituting the polymer 1.

The polymer 3 is, for example, doped (added) vinylphosphonic acid represented by the following formula (a-0) to the polymer 2, followed by addition polymerization of vinylphosphonic acid to the carbon-carbon double bond of the substituent of the polymer 2 It is obtained by the method. As a result, one or more vinylphosphonic acids are additionally bonded to the carbon-carbon double bond, and the structural unit (a) is introduced into the side chain of the polymer 2.

[Formula 9]

There is no restriction | limiting in particular as a method of addition-polymerizing vinylphosphonic acid, The polymerization method which obtains a polymer by addition bond from the vinyl group containing monomer generally known can be employ | adopted.

Specifically, thermal polymerization that generates radical species by heat, and polymerization of radicals generated by decomposition of peroxide, etc., and polymerization of radicals generated by radical irradiation by photoirradiation, and radical polymerization by generating radical species For example, radiation polymerization which generates radical species by radiation irradiation and performs radical polymerization is suitable.

The amount of vinylphosphonic acid introduced, that is, the amount of the structural unit (a), may be 20 mol% to 2000 mol% with respect to one repeating structural unit of the polymer 1, and preferably 50 mol% to 1500 mol%. . For example, 20 mol% means that one repeating structural unit of the polymer 1 has 0.2 structural units (a). For example, 2000 mol% means that one repeating structural unit of the polymer 1 has 20 structural units (a). If it is 20 mol% or more, relatively good power generation characteristics can be expressed, and if it is 2000 mol% or less, the performance can be maintained long-term and stably without oxidation dissolution. It is also advantageous in terms of heat resistance and chemical stability.

By using the conventional solid polymer electrolyte membrane formation method using the polymer compound thus obtained, an electrolyte membrane exhibiting good characteristics can be obtained. Preferably, a mixed solution of the polymer 1 and the molecule introducing the substituents is applied to a glass plate or the like, and the reaction is carried out by heating to obtain a polymer 2 shaped into a rod, followed by treatment with vinylphosphonic acid to be polymer 3, By using this, a solid polymer electrolyte membrane is prepared.

Fuel cell

The fuel cell of the present invention is a fuel cell using the polymer electrolyte membrane obtained according to the above process as an electrolyte membrane. The solid polymer electrolyte membrane is sandwiched between an oxygen electrode and a fuel electrode, and an oxidant bipolar plate having an oxidant flow path is provided on the oxygen electrode side, and a fuel bipolar plate having a fuel flow path is formed on the fuel electrode side as a solid polymer fuel cell. Make.

In this way, even when the operating temperature is 100 to 300 ° C., even when no humidification or relative humidity is 50% or less, a solid polymer fuel cell exhibiting stable power generation performance (durability) for a long time can be obtained. It is useful as a fuel cell.

In the present invention, the reason why such a good characteristic can be exhibited is not determined, but the polybenzimidazoles are obtained by using a polymer compound (polymer 3) having a side chain having a structural unit (a) as an electrolyte membrane of a fuel cell. This is because the side chain having proton conductivity can be stably stored in the electrolyte membrane for a long time as compared with the case where the phosphoric acid compound is simply doped, so that long-term stability of power generation performance can be ensured.

EXAMPLE

Hereinafter, the present invention will be described in more detail with reference to Examples.

In the following examples, the solid polymer electrolyte membranes of Examples 1 to 3 and Comparative Example 1 were prepared, the doping amount of vinylphosphonic acid was measured, and each solid polymer electrolyte was interposed in a fuel cell to generate power generation characteristics ( The initial development and changes over time) were evaluated.

In the measurement of the power generation characteristics of the fuel cell, the electrolyte membrane was sandwiched with a commercially available fuel cell electrode (Electrochemist) to form a membrane electrode assembly, and the fuel cell operation was carried out with hydrogen / air under no humidification conditions. The electrode area was 3 cm 3 cm = 9 cm ² , and the gas supply amount was 50 mL / min for hydrogen and 100 mL / min for air.

Example 1

As polybenzimidazoles, poly-2,2 '-(m-phenylene) -5,5'-bibenzimidazole (weight average molecular weight 150,000 in terms of polystyrene) was N, N- in a proportion of 10% by weight. A solution dissolved in dimethylacetamide was prepared, and 2-isocyanatoethyl methacrylate (trade name: Carens MOI, manufactured by Showa Electric Co., Ltd.) was used as the nitrogen-containing heterocyclic activity to form polybenzimidazoles. 1 equivalent was added to hydrogen to make a mixed solution.

The solution was developed on a glass plate using a doctor blade, heated to 150 ° C. to proceed with the removal of solvent and the reaction shown in Scheme 1, and carbon-carbon double bonds to the nitrogen-containing heterocyclic nitrogen atoms constituting the polybenzimidazoles. The polymer compound film which the substituent which has the bond was obtained.

Vinyl phosphonic acid whose temperature was adjusted to 70 ° C. by adding 1000 ppm of 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane (manufactured by Nippon Oil Holding Co., Ltd., perhexer 25B) as the organic peroxide. It was directly deposited to Tokyo Chemical Co., Ltd. and doped with a mixture of vinylphosphonic acid and organic peroxide over 2 hours.

By heat treatment at 170 ° C. for 2 minutes, poly-2,2 ′-(m-phenylene) -5,5 using 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane as an initiator Radical polymerization of a carbon-carbon double bond having a substituent introduced to a nitrogen-containing heterocyclic nitrogen atom constituting '-bibenzimidazole and vinylphosphonic acid was performed to prepare the solid polymer electrolyte membrane of Example 1.

The amount of vinyl phosphonic acid introduced was measured by washing the solid polymer electrolyte membrane obtained after radical polymerization in hot water at 100 ° C. for 2 hours, removing unreacted vinyl phosphonic acid from the solid polymer electrolyte membrane, and then vacuum drying at 120 ° C. for 2 hours. The measurement was carried out and calculated from the weight change was 500 mol% per repeat structural unit of poly-2,2 '-(m-phenylene) -5,5'-bibenzimidazole.

In addition, before weighing, vacuum drying at 120 ° C. was performed for 2 hours to exclude the influence of moisture absorption. The power generation characteristics of the solid polymer electrolyte membrane thus obtained as a fuel cell were measured by the above-described method.

Table 1 shows the open circuit voltage and the output voltage at a current density of 0.3 A / cm ² after the initial generation and after 200 hours.

Figure 1 shows the current-voltage characteristics of the initial generation, and Figure 2 shows the change over time of the output voltage at the open circuit voltage and current density 0.3A / cm ² .

Example 2

Polymerization was carried out in the same manner as in Example 1 except that the reaction of Scheme (2) was carried out using glycidyl methacrylate (manufactured by Tokyo Chemical Co., Ltd.) instead of 2-isocyanatoethyl methacrylate. A compound film was obtained.

Vinylphosphonic acid was introduced into the polymer compound film in the same manner as in Example 1, and the solid polymer electrolyte membrane of Example 2 having an introduction amount of 450 mol% was obtained.

Using the solid polymer electrolyte membrane, power generation characteristics were measured as a fuel cell in the same manner as in Example 1.

Table 1 shows the open circuit voltage and the output voltage at a current density of 0.3 A / cm ² after the initial generation and after 200 hours.

Comparative Example 1

The solid polymer electrolyte membrane of Comparative Example 1 was prepared by doping 600 mol% of phosphoric acid to poly-2,2 '-(m-phenylene) -5,5'-bibenzimidazole (weight average molecular weight 150,000 determined by polystyrene substitution). Got it.

Power generation characteristics of the solid polymer electrolyte membrane were measured as a fuel cell in the same manner as in Example 1.

Table 1 below shows the starting circuit voltage and the output voltage at a current density of 0.3 A / cm ² after initial generation and after curing for 200 hours.

Fig. 1 shows the current-voltage characteristics of the initial generation, and Fig. 2 shows the change over time of the open circuit voltage and the output voltage at a current density of 0.3 A / cm ² .

TABLE 1

Example 1 Example 2 Comparative Example 1 Early Open circuit voltage (V) 0.933 0.930 0.951 Voltage (0.3 A / cm ² ) 0.602 0.582 0.546 After 200 hours Open circuit voltage (V) 0.923 0.913 0.888 % Drop in open circuit voltage (V) 1.1 1.8 6.6 Voltage (0.3 A / cm ² ) 0.595 0.575 0.488 % Drop in voltage (0.3 A / cm ² ) 1.2 1.2 10.6

Table 1 shows the initial open circuit voltage, the open circuit voltage after 200 hours, and the current density with respect to the electrode area for the fuel cells manufactured using the solid polymer electrolyte membranes of Examples 1, 2 and Comparative Example 1. The initial battery voltage at the time of power generation under the condition of 0.3 A / cm ² and the battery voltage after 200 hours from the power generation are shown. In addition, Table 1 also described the reduction rate (%) of the voltage after 200 hours when the initial voltage was 100%.

In the initial state from the results shown in Table 1, no significant difference was observed for the circuit voltage and the voltage of the current density of 0.3 A / cm ² between the Examples and Comparative Examples.

However, after the elapse of 200 hours, it can be seen that the voltage of the fuel cell of Comparative Example 1 is smaller than that of Examples 1 and 2.

1 shows the relationship between the current density in the initial state and the battery voltage in Example 1 and Comparative Example 1. FIG. In the initial state, even if the current density is increased, no significant difference is seen in the battery voltage.

FIG. 2 shows the relationship between the open circuit voltage (OCV: OPEN CIRCUIT VOLTAGE) and the battery voltage during power generation at a current density of 0.3 A / cm ² and the operating time of the fuel cell in Example 1 and Comparative Example 1. FIG. . As shown in FIG. 2, in the case of Comparative Example 1, it was found that either of the voltages decreased as the operation time became longer for a long time.

On the other hand, in Example 1, the fall of a voltage is hardly seen.

As mentioned above, in the Example which concerns on this invention, it became clear that even in 150 degreeC and a non-humidification condition, it was excellent in durability compared with the case of the comparative example 1, and can exhibit favorable power generation performance stably for a long term.

According to the present invention, it is possible to provide a solid polymer electrolyte membrane, a method of manufacturing the same, and a fuel cell using the same, which exhibits a long-term stable performance in an operating temperature of about 100 to 300 ° C. under an operating condition of no humidification or a relative humidity of 50% or less. Can be.

Claims (7)

The side chain containing the structural unit (a) represented by the following formula, A solid polymer electrolyte membrane comprising a polymer compound having a nitrogen-containing heterocyclic nitrogen atom constituting the polybenzimidazoles. [Formula 1]

The solid polymer electrolyte membrane according to claim 1, wherein the structural unit (a) is contained in an amount of 20 mol% to 2000 mol% per repeating structural unit of the polybenzimidazoles. Doping vinylphosphonic acid to a polymer compound having a substituent containing a carbon-carbon double bond to a nitrogen-containing heterocyclic nitrogen atom constituting polybenzimidazoles, and then performing addition polymerization to vinyl the carbon-carbon double bond. A method for producing a solid polymer electrolyte membrane, comprising the step of preparing a polymer compound to which phosphonic acid is additionally polymerized. 4. The polymer compound according to claim 3, wherein the polymer compound in which a substituent having a carbon-carbon double bond is bonded to a nitrogen-containing heterocyclic nitrogen atom constituting the polybenzimidazoles is polybenzimidazole and an isocyanate group or glycidyl in the molecule. A method for producing a solid polymer electrolyte membrane, which is obtained by a reaction between a group and a compound having a carbon-carbon double bond. The compound according to claim 4, wherein the compound having an isocyanate group or glycidyl group and a carbon-carbon double bond in the molecule, 2-isocyanatoethyl methacrylate represented by the following formula (c-1), 2-isocyanatoethyl acrylate represented by the formula (c-2) and glycidyl represented by the formula (c-3) Method for producing a solid polymer electrolyte membrane, characterized in that at least one selected from methacrylates. [Formula 6]

[Formula 7]

[Formula 8]

The method according to claim 3, wherein the polybenzimidazoles A method for producing a solid polymer electrolyte membrane, characterized in that it is selected from polymers represented by the formulas (b-1)-(b-3) and derivatives thereof. [Formula 2]

Wherein n is 10-100,000. Oxygen electrode; Fuel electrode; And An oxidant bipolar plate provided with the solid polymer electrolyte membrane according to claim 1 or 2 interposed between the oxygen electrode and the fuel electrode and having an oxidant flow path provided on an oxygen electrode side, and a fuel bipolar plate having a fuel flow path formed on the fuel electrode side. A fuel cell comprising a unit cell.

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