JP2006120409A - Proton conductive composite type electrolyte membrane and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a proton conductive composite type electrolyte membrane capable of realizing a fuel cell having high heat-resistance, suppressing swelling caused by containing of water, and corresponding to operation in a high-temperature region, and to provide the manufacturing method of the proton conductive composite type electrolyte membrane. <P>SOLUTION: The proton conductive composite type electrolyte membrane is formed by arranging a hydrocarbon electrolyte material in globular holes installed in an inorganic porous body, the globular holes have almost equal inner diameter, are thee-dimensionally present on the inside of the porous body, and have communicating holes between adjacent globular holes, and the hydrocarbon electrolyte membrane shows proton conductivity through the communicating holes. The proton conductive composite type electrolyte membrane is manufactured by a mixing process of inorganic sol, globular organic resin and a solvent, a stirring process, a filtration and membrane forming process, an excess water removing process, a drying process, a baking process, an electrolyte material impregnation process, and a drying process. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a proton conductive composite electrolyte membrane and a method for producing the same, and more specifically, to a fuel cell, water electrolysis, hydrohalic acid electrolysis, salt electrolysis, oxygen concentrator, humidity sensor, gas sensor and the like. The present invention relates to a proton conductive composite electrolyte membrane and a method for producing the same.

Fuel cells have high power generation efficiency and excellent environmental load control, and are expected to contribute to solving environmental and energy problems that are currently a major issue in countries that consume large amounts of energy. It is a generational energy supply device.
Fuel cells are classified according to the type of electrolyte. Among them, polymer electrolyte fuel cells are small and can provide high output, so that they can be used for small-sized stationary devices, mobile devices, and portable terminals. Research and development is underway for the application of energy as a source of energy.

  Such a solid polymer electrolyte membrane is a solid polymer material having a hydrophilic functional group such as a sulfonic acid group or a phosphoric acid group in a polymer chain, and is firmly bonded to a specific ion, and is either a cation or an anion. Since it has a property of selectively permeating ions, it is formed into particles, fibers or membranes and used in various applications such as electrodialysis, diffusion dialysis, and battery membranes.

  In addition, solid polymer fuel cells are being actively improved as a power generation means that can provide high overall energy efficiency. The main components are anode and cathode electrodes, a separator plate that forms a gas flow path, and a solid polymer electrolyte membrane that separates the electrodes. Protons generated on the anode catalyst move through the solid polymer electrolyte membrane, reach the cathode catalyst, and react with oxygen. Therefore, the ion conduction resistance between the two electrodes greatly affects the battery performance.

In order to form a fuel cell using the above-mentioned solid polymer electrolyte membrane, it is necessary to join the catalyst of both electrodes and the solid polymer electrolyte membrane by an ion conduction path. For this purpose, a catalyst layer in which a polymer electrolyte solution and catalyst particles are mixed, applied and dried to bond them together is used as an electrode, and the electrode catalyst and the solid polymer electrolyte membrane are pressed under heating. The technique was commonly used.
In general, a polymer in which a sulfonic acid group is introduced into a perfluorocarbon-based main chain is used as a polymer electrolyte responsible for ionic conduction. Specific products include Nafion manufactured by DuPont, Flemion manufactured by Asahi Glass Co., and Aciplex manufactured by Asahi Kasei Co., Ltd. A perfluorosulfonic acid polymer electrolyte is composed of a perfluorocarbon main chain and a side chain having a sulfonic acid group, and the polymer electrolyte is a region mainly composed of a sulfonic acid group and a region mainly composed of a perfluorocarbon main chain. It is thought that the sulfonic acid group phase forms a cluster by microphase separation. The site where the perfluorocarbon main chain aggregates contributes to the chemical stability of the perfluorosulfonic acid electrolyte membrane, and the sulfonic acid groups gather to form a cluster that contributes to ionic conduction. Part.

  As described above, it is difficult to produce a perfluorosulfonic acid electrolyte membrane having both excellent chemical stability and ion conductivity, and there is a drawback that it is very expensive. Therefore, the use of perfluorosulfonic acid is limited, and it is extremely difficult to apply it to a polymer electrolyte fuel cell which is expected to be a power source for a moving body.

  In addition, current polymer electrolyte fuel cells are operated in a relatively low temperature range from room temperature to about 80 ° C. The limitation on the operating temperature is that the fluorine-based membrane used has a glass transition point in the vicinity of 120 to 130 ° C., and it becomes difficult to maintain an ion channel structure that contributes to proton conduction in a higher temperature region. Therefore, it is substantially desirable to use at 100 ° C. or lower, and since water is used as a proton conducting medium, pressurization is required when the water boiling point exceeds 100 ° C., and the apparatus becomes large. . The low operating temperature results in low power generation efficiency for the fuel cell and significant poisoning of the catalyst by CO. When the operating temperature is 100 ° C. or higher, the power generation efficiency is improved and the waste heat can be used, so that energy can be used more efficiently. Also, considering the application to fuel cell vehicles, if the operating temperature can be raised to 120 ° C, not only the efficiency will be improved, but also the radiator load required for exhaust heat will be reduced, and it will be used in current mobile units. The same specifications as the existing radiator can be applied, so the system can be made compact.

Thus, various studies have been made so far in order to realize operation at higher temperatures. Typically, as an action with a view to reducing the cost of the previous electrolyte membrane, instead of a fluorine membrane, application of an aromatic hydrocarbon polymer material that is inexpensive and excellent in heat resistance to a solid polymer electrolyte Is being considered. For example, various aromatic hydrocarbon solid polymer electrolytes such as sulfonated polyetheretherketone, sulfonated polyethersulfone, sulfonated polyetherethersulfone, sulfonated polysulfide, and polybenzimidazole are studied as solid polymer electrolytes. (For example, see Patent Documents 1 to 6).
JP-A-6-93114 JP-A-9-245818 Japanese Patent Laid-Open No. 11-116679 JP-A-11-672244 Japanese National Patent Publication No. 11-510198 Japanese Patent Laid-Open No. 9-110982

However, the polymer electrolyte material is a very rigid polymer compound, and there is a problem that there is a high possibility of breakage or the like during electrode formation.
These aromatic hydrocarbon polymer materials are modified with acidic groups such as sulfonic acid groups and phosphoric acid groups in order to impart proton conductivity, and are water-soluble or water-swellable. In the case of water-solubility, it cannot be applied to a system that generates water such as a fuel cell. In the case of water-swellability, the electrode is damaged by the stress due to swelling. Can happen.
Furthermore, in order to achieve high proton conductivity, it is desirable to increase the number of acidic groups introduced into the electrolyte. However, if the amount introduced exceeds a certain level, it becomes difficult for the polymer material itself to maintain the membrane shape.

  In this way, ensuring dimensional stability and self-sustainability as an electrolyte membrane related to fuel cell reliability and improving ionic conductivity with the aim of improving battery performance are the sulfonic acid groups and phosphorus introduced into the resin. It is related to the amount of acid groups and the like, and both characteristics are in a trade-off relationship. Therefore, it is difficult to realize an electrolyte membrane having both characteristics because one improvement reduces the other characteristic.

  The present invention has been made in view of such problems of the prior art. The object of the present invention is to have high heat resistance, suppress swelling when containing water, and support operation in a higher temperature range. It is an object of the present invention to provide a proton conductive composite electrolyte membrane that can realize a fuel cell that can be used and a method for manufacturing the same.

  As a result of intensive studies to solve the above problems, the present inventors have arranged a hydrocarbon-based electrolyte material in the spherical pores of the inorganic porous body in which the spherical pores are regularly and three-dimensionally formed. As a result, the present inventors have found that the above problems can be solved, and have completed the present invention.

  According to the present invention, a stable membranous form can be maintained, and higher ion conductivity can be exhibited than when a perfluorosulfonic acid electrolyte material is applied at the same cost.

  Hereinafter, the proton conductive composite electrolyte membrane of the present invention will be described in detail. In the present specification, “%” indicates a mass percentage unless otherwise specified.

The proton conductive composite electrolyte membrane of the present invention is formed by disposing a hydrocarbon-based electrolyte material in a plurality of spherical holes of an inorganic porous body. Each of the spherical holes has a substantially uniform inner diameter and exists three-dimensionally inside the porous body, and communicates with adjacent spherical holes through a communication port. The hydrocarbon-based electrolyte material is disposed (filled) so as to exhibit proton conductivity through the communication port. A schematic structure and a photograph of the present electrolyte membrane are shown in FIG.
As described above, since an inorganic porous body is used as a holding body and an electrolyte material such as an aromatic hydrocarbon polymer having excellent heat resistance can be disposed therein, an electrolyte membrane having excellent heat resistance can be obtained.
In a wet state, the inorganic porous body suppresses the swelling of the hydrocarbon electrolyte material. In particular, since the spherical pores existing in the porous body are formed with a substantially uniform diameter, the porous body receives a uniform and dispersed swelling force against the swelling of the electrolyte material when it contains water. Damage to the electrolyte is suppressed. In other words, the spherical pores of the inorganic porous body have a three-dimensional regular array structure, so that the swelling pressure of the electrolyte material is uniformly applied to the inorganic porous body. Therefore, it is suitable as a support for the electrolyte membrane that swells with water. Yes.
Furthermore, by controlling the spherical pores of the porous body almost evenly, the impregnation state of the electrolyte material becomes good, and the perfluorosulfonic acid electrolyte material that has been used in the past is applied to the same composite type electrolyte membrane. Compared to high proton conductivity.

Here, the inorganic porous body is preferably made of a material that forms an inorganic sol. In this case, a sol-gel method that is a simple inorganic material forming technique can be applied, and an inorganic porous body can be obtained at a low cost.
The material forming the inorganic sol is preferably an inorganic colloid. By using an inorganic colloid, an inorganic porous body having a regularly arranged shape using polymer particles as a template can be formed.
Furthermore, the inorganic porous body preferably includes, for example, those related to silica, titania, zirconia, or tantalum, and any combination thereof. At this time, it can be an inorganic colloid that can withstand practical use.
The inorganic porous body is obtained from, for example, a suspension obtained by mixing polymer fine particles and an inorganic material. By applying such a suspension, an inorganic porous body can be obtained using a three-dimensional regular array structure formed by stacking polymer fine particles as a template. In particular, an inorganic porous body having an arbitrary pore size structure can be designed by controlling the particle size and the lamination state of the polymer fine particles. The polymer fine particles in the pores are removed by heat treatment or the like, so that a space for the electrolyte material is secured.
Thus, by using an inorganic porous body having spherical pores regularly arranged three-dimensionally, it functions as a homogeneous support, and when combined with a polymer electrolyte, the electrolyte is supported by water content. Concentration of swelling force on the electrolyte can be suppressed, and damage to the electrolyte membrane can be prevented. In addition, since a high porosity exceeding 70% can be secured, a large amount of electrolyte material can be introduced, and excellent ion conductivity can be realized.

  On the other hand, as the hydrocarbon electrolyte material, it is preferable to use a material obtained by adding a functional group that expresses proton conductivity to an aromatic hydrocarbon polymer. By applying an aromatic hydrocarbon polymer excellent in heat resistance, an electrolyte membrane excellent in heat resistance can be obtained, and a material cheaper than conventional fluorine-based electrolyte materials can be applied.

Moreover, it is preferable that the hydrocarbon-based electrolyte material has an ion exchange capacity of at least 1 to 6 meq / g. In order to set the ion exchange amount within the above range, for example, the kind of the aromatic hydrocarbon electrolyte, the amount of the proton conductive functional group to be imparted, and the like may be appropriately adjusted. At this time, if the amount of the proton conductive functional group introduced into the aromatic hydrocarbon electrolyte is less than 1 meq / g, sufficient proton conductivity cannot be expressed, and if it exceeds 6 meq / g, the electrolyte material is It becomes difficult to maintain a solid state.
In addition, in the conventional fluorine-based electrolyte membrane represented by Nafion (trademark: manufactured by DuPont), those around 1 meq / g are marketed, but those above 2 meq / g are difficult, so that the present invention Then, an electrolyte membrane having higher proton conductivity than before can be designed.

Furthermore, it is preferable to use a polyether polymer as the hydrocarbon-based electrolyte material. Specifically, as shown in FIG. 2, polyether ether ketone or polyether sulfone obtained by sulfonating a polyether-based substance can be used. Typically, polyether ether sulfone is preferably used.
In this case, an inorganic porous body having a regularly arranged space can be impregnated with more electrolyte material than a conventional fluorine-based electrolyte, and an electrolyte superior in proton conductivity compared with a conventional product is obtained. be able to.

Next, the production method of the proton conductive composite electrolyte membrane of the present invention will be described in detail.
In the production method of the present invention, the following steps (1) to (8):
In producing the described proton conductive composite electrolyte membrane,
(1) Step of mixing inorganic sol and spherical organic resin in solvent (2) Step of stirring this mixed solution (3) Step of forming a film of this mixed solution by filtration (4) Excess water content contained in filtration molded membrane Removal step (5) Filtration molded membrane drying step from which excess water has been removed (6) Filtration molded membrane heating and firing step obtained by drying (7) Hydrocarbon to inorganic porous body obtained by this heating and firing Step of impregnating the system electrolyte material (8) A step of drying the inorganic / organic composite type electrolyte membrane impregnated with the electrolyte material is performed to produce the above-described proton conductive composite type electrolyte membrane. FIG. 3 shows the flow of the manufacturing procedure.

In the step (1) and the step (2), an inorganic porous body composed of a homogeneous inorganic support can be obtained by mixing the inorganic colloid and the organic resin material in a homogeneous state.
In the step (3), the filtration is suitable as a method for filling the gap between the organic resin templates with the inorganic sol. Furthermore, in the step (4), the drying time in the next drying step can be shortened by previously removing the solvent contained in the membrane formed by filtration.
In step (5), the filtration film is dried at room temperature in advance, thereby facilitating the handling of the film in the firing step or the like. Next, in step (6), the filtration film is heated and fired, whereby an inorganic support made of an inorganic sol is fired and a porous material can be formed by baking and removing the template resin.
Further, in the step (7) and the step (8), the intended inorganic / organic composite electrolyte membrane can be easily obtained by impregnating and drying the obtained porous material with an electrolyte material. In particular, the drying time can be shortened by applying a temperature at which the polymer electrolyte does not break during drying, and when the polymer electrolyte is impregnated with a crosslinking agent, the crosslinking reaction is promoted. A strong film can also be obtained.

By passing through the said process (1)-(6), the organic porous material is used as a template and the inorganic porous body by which the three-dimensional regular arrangement was carried out is obtained. In particular, the filtration step (3) is suitable as a method for satisfactorily filling an inorganic colloid using a spherical organic resin as a template. As the spherical organic resin, for example, a polyolefin resin typified by polyethylene of about 100 nm to 1500 nm, a polystyrene resin, a crosslinked acrylic resin, a methyl methacrylate resin, a polyamide resin, and the like can be appropriately selected. If it is smaller than 100 nm, it becomes difficult to obtain particles having a uniform particle size distribution at low cost. On the other hand, if it exceeds 1500 nm, the homogeneity of the support structure constituting the inorganic support is disturbed, which is not preferable.
Further, the filtration can be performed at a reduced pressure of about 10 to 60 kPa as appropriate from the size of the spherical pores of the inorganic porous body, the pore density, and the like.
Furthermore, in the step (6), it is preferable to perform preliminary firing for removing the organic resin material in the filtration membrane and then sinter the inorganic porous body. Temporary baking is performed at a heating rate of 1 to 10 ° C./min, preferably 2 to 5 ° C./min, 400 to 500 ° C., more preferably 430 to 470 ° C., and heat treatment is performed for 30 minutes or longer. Can do. Moreover, baking can perform the heat processing for about 30 to 100 minutes, for example at 800-900 degreeC or more. Further, the main baking may be repeated a plurality of times.
In the step (7), the electrolyte material to be impregnated may be in any form of powder, bead, gel, or solution as long as it can be used for the following impregnation step. In addition, water, linear or branched alcohols typified by methanol, ethanol, n-propanol, isopropanol, etc., olefins such as n-hexane, aromatic solvents typified by cyclohexane, toluene and xylene, dimethyl ether Ethers such as ethyl acetate, methyl acetate, acetonitrile, dimethyl sulfoxide (DMSO), dichloroethane (EDC), dioxane, tetrahydrofuran (THF), dimethylformamide (DMF), N-methylpyrrolidone (NMP), etc. Can be appropriately selected from the above and used as an impregnation solution. In use, the above solvents may be used singly or plural may be appropriately selected and mixed.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in full detail, this invention is not limited to these Examples.

Example 1
By using a porous silica membrane as a matrix and introducing a conductive polymer into the pores, an inorganic / organic composite type electrolyte membrane was prepared.
1) Production of inorganic porous body As an organic resin material for controlling the pore diameter of the inorganic porous body, polystyrene spherical particles having an average diameter of about 500 nm were used.
The polystyrene spherical particles and colloidal silica having a diameter of 70 to 100 nm were mixed and prepared so that the solute volume contained in the suspension solution had a predetermined film thickness. As a procedure, first, a predetermined amount of polystyrene was weighed and added to water, and then a solution containing colloidal silica was added to a solution containing polystyrene spherical fine particles. In order to disperse these particles uniformly, ultrasonic stirring was performed.

Next, inorganic porous material was formed by filtration of the suspension solution. The membrane filter was set in a filter holder, the pressure was reduced to a pressure of 10 kPa or less with respect to atmospheric pressure using a manual vacuum pump, and the suspension solution was filtered.
After all of the suspended solution has been filtered, the excess solvent contained in the filter-formed membrane is removed using excess water such as filter paper as a water-absorbing material, and after sufficient drying at room temperature, it is peeled off from the membrane filter. Thus, a film made of a mixture of polystyrene and silica was obtained.
This mixture film was heat-treated as follows. First, in order to remove polystyrene, the temperature was raised to 450 ° C. at a temperature raising rate of 3 ° C./min, and calcination was performed at that temperature for 60 minutes. Moreover, in order to sinter the silica, a heat treatment was performed at 800 ° C. or higher for about 60 minutes after the preliminary firing. In order to further improve the mechanical strength, heat treatment was performed at a temperature of 900 ° C. or higher for 15 minutes, and the temperature was slowly returned to room temperature, thereby obtaining a target inorganic porous material.

2) Impregnation of polymer electrolyte material A polyether electrolyte material was produced by sulfonating a commercially available polymer. Poly (oxy-1,4-phenylene-1,4-phenylenesulfyl-1,4-phenylene) was used as a starting material, and a polymer electrolyte material obtained by sulfonating this was used. The synthesized polymer solution was introduced into the pores to produce a composite electrolyte membrane. Specifically, a composite electrolyte membrane was produced by impregnating a porous silica membrane with a sulfonated polyether electrolyte aqueous solution adjusted to a predetermined concentration and evaporating water. A cross-sectional SEM image of the obtained inorganic / organic composite electrolyte membrane is shown in FIG. From this, it was observed that the electrolyte resin was present on the surface of the inorganic porous body.
Moreover, the amount of sulfonic acid groups per unit weight constituting the dried aromatic hydrocarbon polymer was determined by neutralization titration, and the ion exchange capacity of the obtained electrolyte material was calculated. Here, an ion exchange capacity of 3.2 meq / g was used. This value is more than three times the ion exchange capacity of Nafion, which is a typical fluorine-based electrolyte membrane, and the obtained polymer electrolyte material has a high sulfonic acid group density, which is more advantageous for the expression of proton conductivity. It was something that worked.

(Comparative Example 1)
A composite electrolyte membrane was prepared by repeating the same operation as in Example 1 except that a Nafion (trademark: manufactured by DuPont) solution was used as the polymer electrolyte material impregnated in the inorganic porous body. For impregnation, a 20% Nafion solution was used, and after dripping and impregnating the Nafion solution on the surface of the porous silica membrane produced in the same manner as in Example 1, the solvent was evaporated in a dryer to remove Nafion. An impregnated membrane was obtained.

(Evaluation measurement)
1) Quantification of ion conductive functional group introduced into inorganic / organic composite electrolyte membrane The inorganic / organic composite electrolyte membrane obtained in Example 1 was bound to the polymer electrolysis mass impregnated in the electrolyte membrane. The amount of introduced functional groups responsible for proton conductivity was analyzed by compositional element analysis of the sample using energy dispersive X-ray spectroscopy (EDS method). The EDS method can measure the energy of characteristic X-rays emitted from a sample and perform composition element analysis of the sample. The analysis results are shown in FIG.
As shown in FIG. 5, Si element constituting the inorganic porous material and S element derived from the sulfonic acid group responsible for proton conduction introduced into the aromatic hydrocarbon polymer electrolyte are detected in the EDS spectrum. From these detection peaks, the amount of each element was calculated by sensitivity correction, and the element ratio S / Si was obtained.

In the electrolyte membrane of Example 1, it was found that S / Si = 15.9 and a sufficient electrolytic mass was present. On the other hand, the Nafion impregnated film obtained in Comparative Example 1 had S / Si of less than 0.1. Thus, in the electrolyte membrane of the present invention, more electrolyte is introduced into the inorganic porous body than the Nafion-impregnated membrane.
At present, this mechanism is not clear, but according to the results of Gebel's X-ray and neutron scattering measurements (G. Gebel, Polymer, 41, 5829-5838 (2000)), Nafion in the solution state is composed of polymers. It has been reported that sulfonic acid groups surround the network and water surrounds the rod-shaped formation. From this, it can be inferred that the polymer micelles configured in this rod shape inhibit the introduction of Nafion into the inorganic porous pores whose pores are controlled in the nanometer order.

2) Proton conductivity evaluation of the inorganic / organic composite electrolyte membrane The proton conductivity of the obtained composite electrolyte membrane was measured by placing a gold electrode with a predetermined area between both sides and applying an AC wave of 100 Hz to 1 MHz. The impedance was evaluated. The ionic conductivity here was calculated based on the area in contact with the gold electrode without considering the porosity. The measurement was performed by adjusting the environment of temperature and humidity so that the water vapor partial pressure was saturated. The result is shown in FIG.

  As shown in FIG. 6, the electrolyte membrane obtained in Example 1 showed higher ionic conductivity than the Nafion-impregnated membrane. On the other hand, in the Nafion-impregnated membrane, the dimensional change was clearly confirmed visually. However, the electrolyte membrane obtained in Example 1 was not visually recognized even when the environmental humidity was changed, and the electrolyte swelled with water content. The effect was recognized.

It is the schematic which shows the structure of the electrolyte membrane of this invention typically. 2 is a structural formula showing an example of a polyether-based polymer. It is a flowchart which shows the preparation procedures of a proton conductive composite type electrolyte membrane. It is a photograph which shows the cross-sectional SEM image of a composite type electrolyte membrane. It is a graph which shows the example of a measurement of an EDS spectrum. 3 is a graph showing proton conductivity of electrolyte membranes obtained in Example 1 and Comparative Example 1. FIG.

Claims (10)

A proton conductive composite electrolyte membrane comprising a hydrocarbon electrolyte material disposed in a plurality of spherical pores of an inorganic porous body,
The spherical holes have a substantially uniform inner diameter and are three-dimensionally present inside the porous body and have a communication port between adjacent spherical holes, and the hydrocarbon electrolyte material passes through the communication port. A proton conductive composite electrolyte membrane characterized by exhibiting proton conductivity.   2. The proton conductive composite electrolyte membrane according to claim 1, wherein the inorganic porous body is made of a material that forms an inorganic sol.   3. The proton conductive composite electrolyte membrane according to claim 2, wherein the material forming the inorganic sol is an inorganic colloid.   The proton conductive composite according to any one of claims 1 to 3, wherein the inorganic porous material includes at least one selected from the group consisting of silica, titania, zirconia and tantalum. Type electrolyte membrane.   The proton conductive composite electrolyte membrane according to any one of claims 1 to 4, wherein the inorganic porous material is obtained from a suspension obtained by mixing polymer fine particles and an inorganic material.   The proton according to any one of claims 1 to 5, wherein the hydrocarbon electrolyte material is formed by adding a functional group that expresses proton conductivity to an aromatic hydrocarbon polymer. Conductive composite electrolyte membrane.   The proton conductive composite electrolyte membrane according to any one of claims 1 to 6, wherein the hydrocarbon electrolyte material has an ion exchange capacity of at least 1 meq / g to 6 meq / g.   The proton conductive composite electrolyte membrane according to any one of claims 1 to 7, wherein the hydrocarbon-based electrolyte material is made of a polyether-based polymer.   The proton conductive composite electrolyte membrane according to any one of claims 1 to 8, wherein the hydrocarbon electrolyte material is polyether ether sulfone. In producing the proton conductive composite electrolyte membrane according to any one of claims 1 to 9,
A step of mixing the inorganic sol and the spherical organic resin using a solvent, a step of stirring the mixed solution, a step of forming a film of the mixed solution by filtration, a step of removing excess water contained in the filtration molded membrane, A step of drying the filtration molded membrane from which excess water has been removed, a step of heating and baking the filter molded membrane obtained by drying, and a step of impregnating the hydrocarbon-based electrolyte material into the inorganic porous body obtained by heating and baking And a step of drying the composite electrolyte membrane impregnated with the electrolyte material. A method for producing a proton-conductive composite electrolyte membrane.

Images