KR20070090557A - Method for producing polymer electrolyte membrane for fuel cell - Google Patents

Abstract

The present invention relates to a method for producing a polymer electrolyte membrane for a fuel cell, wherein the manufacturing method is applied to a release film to form a polymer electrolyte membrane-forming composition to form a polymer electrolyte layer, the polymer electrolyte layer is separated from the release film to a polymer electrolyte A process for producing the membrane.

The present invention can easily produce a polymer electrolyte membrane by using a release film in the production of a polymer electrolyte membrane, thereby easily forming a pattern and minimizing damage to the polymer electrolyte membrane during peeling from the release film. In addition, the prepared polymer electrolyte membrane may have a uniform thickness and pattern to improve the performance of the fuel cell.

Description

Manufacturing method of polymer electrolyte membrane for fuel cell {METHOD OF PREPARING POLYMER MEMBRANE}

1 is a view schematically showing a membrane-electrode assembly for a fuel cell according to an embodiment of the present invention,

2 is a view schematically showing the structure of a fuel cell system according to another embodiment of the present invention.

[Industrial use]

The present invention relates to a method for producing a polymer electrolyte membrane for a fuel cell, and more particularly, to a method for producing a polymer electrolyte membrane for a fuel cell that is easy to form a pattern and minimizes damage to the polymer electrolyte membrane during peeling from a release film. .

[Prior art]

A fuel cell is a power generation system that directly converts the chemical reaction energy of hydrogen and oxygen contained in hydrocarbon-based materials such as methanol, ethanol and natural gas into electrical energy.

This fuel cell is a clean energy source that can replace fossil energy, and has the advantage of generating a wide range of outputs by stacking unit cells, and having an energy density of 4-10 times that of a small lithium battery. It is attracting attention as a compact and mobile portable power source.

Representative examples of the fuel cell include a polymer electrolyte fuel cell (PEMFC) and a direct oxidation fuel cell (Direct Oxidation Fuel Cell). The use of methanol as fuel in the direct oxidation fuel cell is called a direct methanol fuel cell (DMFC).

The polymer electrolyte fuel cell has an advantage of having a high energy density and a high output, but requires attention to handling hydrogen gas and reforms fuel for reforming methane, methanol, natural gas, etc. to produce hydrogen as fuel gas. There is a problem that requires additional equipment such as a device.

On the other hand, the direct oxidation fuel cell has a lower energy density than the polymer electrolyte fuel cell, but it is easy to handle fuel and has a low operating temperature, so that it can be operated at room temperature, in particular, it does not require a fuel reformer.

In such fuel cell systems, the stack that substantially generates electricity comprises several unit cells consisting of a membrane-electrode assembly (MEA) and a separator (also called a bipolar plate). It has a structure laminated to several tens. The membrane-electrode assembly is called an anode electrode (also called "fuel electrode" or "oxidation electrode") and a cathode electrode (also called "air electrode" or "reduction electrode") with a polymer electrolyte membrane containing hydrogen ion conductive polymer therebetween. Has a structure in which

The principle of generating electricity in a fuel cell is that fuel is supplied to an anode electrode, which is a fuel electrode, adsorbed to a catalyst of the anode electrode, and the fuel is oxidized to generate hydrogen ions and electrons. Reaching the cathode electrode, hydrogen ions pass through the polymer electrolyte membrane and are delivered to the cathode electrode. An oxidant is supplied to the cathode, and the oxidant, hydrogen ions, and electrons react on the catalyst of the cathode to generate electricity while producing water.

An object of the present invention is to provide a method for producing a polymer electrolyte membrane for a fuel cell that is easy to form a pattern and can minimize damage of the polymer electrolyte membrane during peeling.

In order to achieve the above object, the present invention is a fuel comprising a step of applying a composition for forming a polymer electrolyte membrane to a release film to form a polymer electrolyte layer, and separating the polymer electrolyte layer from the release film to produce a polymer electrolyte membrane A method for producing a polymer electrolyte membrane for batteries is provided.

Hereinafter, the present invention will be described in more detail.

The polymer electrolyte membrane of the fuel cell serves as an insulator for electrically separating the anode electrode and the cathode electrode, or acts as a medium for transferring hydrogen ions from the anode electrode to the cathode electrode during cell operation, and simultaneously serves to separate the reaction gas or liquid. . Therefore, the polymer electrolyte membrane should have excellent electrochemical stability, low ohmic loss at high current density, excellent resolution of reactants during cell operation, and a certain level of mechanical properties and dimensional stability for stack construction. Is required.

In general, a polymer electrolyte membrane is prepared by a solvent casting method of coating a resin composition comprising a polymer resin having a hydrogen ion conductivity and a solvent on a glass substrate.

However, at this time, if the surface of the glass substrate is not smooth and fine, it is difficult to form a polymer electrolyte membrane having a uniform thickness as a whole, and there is a problem that the film is damaged when peeling from the glass substrate after the film formation.

In contrast, in the present invention, by using a release film instead of the glass substrate, damage to the polymer electrolyte membrane upon peeling from the substrate can be minimized, and a pattern can be easily formed on the polymer electrolyte membrane. In addition, the prepared polymer electrolyte membrane may have a uniform thickness and pattern to improve the performance of the fuel cell.

That is, in the method of manufacturing a polymer electrolyte membrane according to an embodiment of the present invention, a polymer electrolyte membrane-forming composition is applied to a release film to form a polymer electrolyte layer, and the polymer electrolyte layer is separated from the release film to prepare a polymer electrolyte membrane. It includes a process to make.

The polymer electrolyte membrane-forming composition may be prepared by dissolving a cation exchange resin in a solvent.

As the cation exchange resin, any of a cationic polymer resin having hydrogen ion conductivity can be used. Representative examples thereof include a polymer resin having a cation exchange group selected from the group consisting of sulfonic acid group, carboxylic acid group, phosphoric acid group, phosphonic acid group and derivatives thereof in the side chain.

Representative examples of the polymer resin include a fluorine polymer, a benzimidazole polymer, a polyimide polymer, a polyetherimide polymer, a polyphenylene sulfide polymer, a polysulfone polymer, a polyether sulfone polymer and a polyether ketone At least one hydrogen ion conductive polymer selected from a polymer, a polyether-etherketone-based polymer and a polyphenylquinoxaline-based polymer may be used, and more preferably poly (perfluorosulfonic acid), poly (perfluorocarboxyl) Acid), copolymers of tetrafluoroethylene and fluorovinyl ether containing sulfonic acid groups, defluorinated sulfide polyether ketones, aryl ketones, poly (2,2'-m-phenylene) -5,5'-bi One or more selected from the group consisting of benzimidazole (poly (2,2 '-(m-phenylene) -5,5'-bibenzimidazole) and poly (2,5-benzimidazole) can be used.

As said solvent, the solvent which shows polarity is preferable, For example, Water; Alcohol solvents such as methanol, ethanol and isopropyl alcohol; Amide solvents such as N, N-dimethylacetamide (DMAC), N-methyl pyrrolidone (NMP) and dimethylformamide (DMF); And sulfoxide solvents such as dimethyl sulfoxide and the like.

The polymer electrolyte membrane-forming composition may further include an inorganic additive for increasing hydrogen ion conductivity of the polymer electrolyte membrane.

Examples of the inorganic additives include silica (fumed silica), trade names include Aerosil, Cab-O-sil, etc., alumina, mica, and zeolite (trade names SAPO-5, XSM-5, AIPO- 5, VPI-5, MCM-41, etc.), barium titanate, ceramic, inorganic silicate, zirconium hydrogen phosphate, α-Zr (O _a1 PCH _a2 OH) _a (O _b1 PC _b2 H _b4 SO _b5 H) _b · nH ₂ O (where, a1, a2, a, b1 , b2, b4, b5 and b are the same or independently represent an integer of 0 to 14 to each other, n is an integer of 0 to 50), ν-Zr ( PO _a1 ) (H _a2 PO _a3 ) _a (HO _b1 PC _b2 H _b3 SO _b4 H) _b nH ₂ O (where a1, a2, a3, a, b1, b2, b3, b4 and b are the same or Independently of each other, an integer from 0 to 14, n is an integer from 0 to 50), Zr (O _a1 PC _a2 H _a3 ) _a Y _b (where a1, a2, a3, a and b are the same or independently of each other) an integer of from 0 to _{14), Zr (O a1 PCH} a2 OH) a Y b · nH 2 O ( where, a1, a2, a and b are same or Are independently from 0 to 14, an integer to each other, n is an integer of 0 to 50), α-Zr (O a1 PC a2 H a3 SO a4 H) a · nH 2 O ( where, a1, a2, a3, a4 and a is the same or independently of each other is an integer from 0 to 14, n is an integer from 0 to 50), α-Zr (O _a1 POH) H ₂ O (where a1 is an integer from 0 to 14), (P ₂ O ₅ ) _a (ZrO ₂ ) _b (where a and b are the same or independently of each other an integer from 0 to 14) glass and P ₂ O ₅ -ZrO ₂ -SiO ₂ One or more mixtures selected from the group consisting of glass are preferred, with inorganic silicates being most preferred.

The prepared polymer electrolyte membrane-forming composition may preferably have a viscosity of 2000 to 10000 cps, and more preferably 3000 to 7000 cps. If the viscosity of the composition is less than 2000 cps, uniform dispersion and stability are inferior, and if it is more than 100 cps, coating becomes uneven, which is not preferable.

Thereafter, the prepared polymer electrolyte membrane-forming composition may be uniformly mixed by mechanical mixing or ultrasonic mixing.

The polymer electrolyte membrane-forming composition prepared as described above is applied to one surface of a release film and dried to form a polymer electrolyte layer.

In this case, as the release film, polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene / tetra Fluorine-based resin films such as fluoroethylene (Ethylene / Tetrafluoroethylene (ETFE)), polyvinylidene fluoride, or polyimide (Kapton ^® , manufactured by DuPont), polyethylene, polypropylene, polypropylene, polyethylene Non-fluorine-based polymer films such as terephthalate (polyethylene terephthalate) or polyester (Mylar ^® , manufactured by DuPont) can be used.

The thickness of the release film is preferably 50 to 100 μm, and when the thickness of the release film is less than 50 μm, it is easy to tear during peeling of the polymer electrolyte membrane, and thus, it is difficult to control the tension. Is not

In addition, the release film may have a pattern. Accordingly, when the polymer electrolyte membrane having a pattern is to be manufactured, the pattern may be formed simultaneously with the preparation of the electrolyte membrane without the need for undergoing an additional pattern forming process for the prepared polymer electrolyte membrane.

The pattern formed on the release film may be formed in an appropriate shape according to the pattern to be formed on the polymer electrolyte membrane, and the pattern formation method on the release film may be formed using a conventional pattern formation method.

The coating process of the composition for forming the polymer electrolyte film to the release film may be screen printing, spray coating, coating using a doctor blade, gravure coating, dip coating, silk screening, painting, depending on the viscosity of the composition. And the slot die (slot die) method may be performed by a method selected from the group consisting of, but is not limited thereto. More preferably, the doctor blade method can be used.

Thereafter, the coated polymer electrolyte membrane-forming composition is dried to form a polymer electrolyte layer.

Subsequently, the polymer electrolyte layer may be separated from the release film to prepare a polymer electrolyte membrane.

The polymer electrolyte membrane prepared by the manufacturing method as described above has no damage to the membrane upon separation from the release film, and has a uniform thickness as a whole.

The polymer electrolyte membrane prepared as described above may be positioned between the cathode electrode and the anode electrode to form a membrane-electrode assembly.

1 is a schematic cross-sectional view of a membrane-electrode assembly for a fuel cell of the present invention.

Referring to FIG. 1, the membrane-electrode assembly 10 according to an exemplary embodiment of the present invention may include the polymer electrolyte membrane 50 and the fuel cell electrodes 20 and 20 disposed on both surfaces of the polymer electrolyte membrane 50, respectively. Include '). The electrode includes electrode substrates 40 and 40 'and catalyst layers 30 and 30' formed on the surface of the electrode substrate.

In the membrane-electrode assembly 10, the electrode 20 disposed on one surface of the polymer electrolyte membrane 50 is called an anode electrode (or a cathode electrode), and the electrode 20 ′ disposed on the other surface is called a cathode electrode ( Or anode electrode). The anode electrode 20 causes an oxidation reaction to generate hydrogen ions and electrons from the fuel delivered to the catalyst layer 30 through the electrode base 40, and the polymer electrolyte membrane 50 is hydrogen generated from the anode electrode 20. Ions are moved to the cathode electrode 20 ', and the cathode electrode 20' passes through the hydrogen ions supplied through the polymer electrolyte membrane 50 and the electrode base 40 'and is transferred to the catalyst layer 30'. Causes a reduction reaction to produce water.

 The electrode substrates 40 and 40 'play a role of supporting the electrode while diffusing the fuel and the oxidant to the catalyst layer, thereby serving to easily access the fuel and the oxidant to the catalyst layer. The electrode substrate is a conductive substrate, and representative examples thereof include carbon paper, carbon cloth, carbon felt, or metal cloth (porous film or polymer fiber composed of metal cloth in a fibrous state). The metal film is formed on the surface of the cloth formed of (referred to as metalized polymer fiber) may be used, but is not limited thereto.

In addition, it is preferable to use a water-repellent treatment with a fluorine-based resin as the electrode base material because it can prevent the reactant diffusion efficiency from being lowered by water generated when the fuel cell is driven. As the fluorine-based resin, polyvinylidene fluoride, polytetrafluoroethylene, fluorinated ethylene propylene, polychlorotrifluoroethylene, or fluoroethylene polymer may be used.

The catalyst layers 30 and 30 'catalyze the related reactions (oxidation of fuel and reduction of oxidant) and include a metal catalyst and a binder resin.

The metal catalyst may be platinum, ruthenium, osmium, platinum-ruthenium alloy, platinum-osmium alloy, platinum-palladium alloy, platinum-M alloy, platinum-ruthenium-M alloy (M = Ga, Ti, V, Sn, W, One or more selected from the group consisting of Rh, Mo, Cr, Mn, Fe, Co, Ni, Cu, and Zn). As described above, the anode electrode and the cathode electrode may use the same material, but in order to prevent the catalyst poisoning caused by CO generated during the anode electrode reaction in the direct oxidation fuel cell, a platinum-ruthenium alloy catalyst is used as the anode. It is more preferable as an electrode catalyst. Representative examples include Pt, Pt / Ru, Pt / W, Pt / Ni, Pt / Sn, Pt / Mo, Pt / Pd, Pt / Fe, Pt / Cr, Pt / Co, Pt / Ru / W, Pt / One or more selected from the group consisting of Ru / Mo, Pt / Ru / V, Pt / Fe / Co, Pt / Ru / Rh / Ni, and Pt / Ru / Sn / W can be used.

In addition, such a metal catalyst may be used as the metal catalyst (black) itself, or may be supported on a carrier. As the carrier, carbon such as acetylene black, denka black, activated carbon, ketjen black, graphite may be used, or inorganic fine particles such as alumina, silica, titania, zirconia may be used, but carbon is generally used.

The catalyst layer may further include a binder resin for improving the adhesion of the catalyst layer and the transfer of hydrogen ions.

It is preferable to use a polymer resin having hydrogen ion conductivity as the binder resin, more preferably a cation exchange group selected from the group consisting of sulfonic acid group, carboxylic acid group, phosphoric acid group, phosphonic acid group and derivatives thereof in the side chain. Any polymer resin which has can be used. Preferably examples include fluorine polymer, benzimidazole polymer, polyimide polymer, polyetherimide polymer, polyphenylene sulfide polymer, polysulfone polymer, polyether sulfone polymer, polyether ketone polymer, One or more hydrogen ion conductive polymers selected from polyether-etherketone-based polymers and polyphenylquinoxaline-based polymers may be used, and more preferably poly (perfluorosulfonic acid) and poly (perfluorocarboxylic acid) , Copolymers of tetrafluoroethylene and fluorovinyl ether containing sulfonic acid groups, defluorinated sulfide polyether ketones, aryl ketones, poly (2,2'-m-phenylene) -5,5'-bibenziimi One or more hydrogen ion conductive polymers selected from the group consisting of poly (2,2 '-(m-phenylene) -5,5'-bibenzimidazole) and poly (2,5-benzimidazole)It can be used.

The binder resin may be used in the form of a single substance or a mixture, and may also be optionally used with a non-hydrogen ion conductive polymer for the purpose of further improving adhesion to the polymer electrolyte membrane. It is preferable to adjust the usage-amount so that it may be suitable for a purpose of use.

The non-hydrogen ion conductive polymer may be polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoro alkyl vinyl ether copolymer, ethylene / tetrafluoro Ethylene (ethylene / tetrafluoroethylene (ETFE)), ethylenechlorotrifluoro-ethylene copolymer (ECTFE), polyvinylidene fluoride, copolymers of polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP), dodecyl At least one selected from the group consisting of benzenesulfonic acid and sorbitol is more preferred.

In addition, a microporous layer may be further included on the electrode substrate to enhance the diffusion effect of the reactants on the electrode substrate. These microporous layers are generally conductive powders having a small particle diameter, such as carbon powder, carbon black, acetylene black, activated carbon, carbon fiber, fullerene, carbon nanotubes, carbon nanowires, and carbon nanohorns. -horn or carbon nano ring.

The microporous layer is prepared by coating a composition comprising a conductive powder, a binder resin and a solvent on the electrode substrate. As the binder resin, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl alcohol, cellulose acetate, and the like may be preferably used. The solvent may be ethanol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, or the like. Alcohol, water, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone and the like can be preferably used. The coating process may be screen printing, spray coating, or coating using a doctor blade according to the viscosity of the composition, but is not limited thereto.

The fuel cell electrode having the above structure may be used as at least one of an anode or a cathode, and more preferably, both.

The membrane-electrode assembly including such an electrode includes a polymer electrolyte membrane 50 positioned between the anode and the cathode electrode.

The polymer electrolyte membrane functions as an ion exchange to transfer hydrogen ions generated in the catalyst layer of the anode electrode to the catalyst layer of the cathode electrode, which is the same as described above.

The membrane-electrode assembly comprising the polymer electrolyte membrane can be applied to a fuel cell system.

The fuel cell system of the present invention includes at least one electricity generating portion, a fuel supply portion and an oxidant supply portion.

The electricity generating portion includes a membrane-electrode assembly and a separator (also called bipolar plate). The membrane-electrode assembly includes a polymer electrolyte membrane and cathode and anode electrodes existing on both sides of the polymer electrolyte membrane. The electricity generation unit serves to generate electricity through the oxidation reaction of the fuel and the reduction reaction of the oxidant.

The fuel supply unit serves to supply fuel to the electricity generation unit, and the oxidant supply unit serves to supply an oxidant such as oxygen or air to the electricity generation unit.

In the present invention, the fuel may include hydrogen or hydrocarbon fuel in gas or liquid state. Representative examples of the hydrocarbon fuel include methanol, ethanol, propanol, butanol or natural gas.

A schematic structure of the fuel cell system of the present invention is shown in FIG. 2, which will be described in more detail with reference to the following. Although the structure shown in FIG. 2 shows a system for supplying fuel and oxidant to an electric generator using a pump, the fuel cell system of the present invention is not limited to such a structure, and a fuel cell using a diffusion method without using a pump is shown. Of course, it can also be used for system architecture.

The fuel cell system 100 of the present invention includes at least one electricity generation unit 115 for generating electrical energy through an oxidation reaction of a fuel and a reduction reaction of an oxidant, a fuel supply unit 120 for supplying the fuel, And an oxidant supply unit 130 for supplying an oxidant to the electricity generating unit 115.

In addition, the fuel supply unit 120 for supplying the fuel may include a fuel tank 122 storing fuel and a fuel pump 124 connected to the fuel tank 122. The fuel pump 124 serves to discharge the fuel stored in the fuel tank 122 by a predetermined pumping force.

The oxidant supply unit 130 supplying the oxidant to the electricity generating unit 115 includes at least one oxidant pump 132 that sucks the oxidant with a predetermined pumping force.

The electricity generator 115 includes a membrane-electrode assembly 112 for oxidizing and reducing a fuel and an oxidant, and a separator 114 and 114 'for supplying fuel and an oxidant to both sides of the membrane-electrode assembly. At least one electricity generating unit 115 gathers to form a stack 110.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited to the following examples.

(Example 1)

A commercially available 5 wt% Nafion / H ₂ O / 2-propanol (Solution Technology Inc., EW = 1,100) solution was stirred at room temperature and evaporated under reduced pressure, and then dimethylacetamide (DMAc) at a concentration of 10 wt%. ) Was added and mechanically stirred at 100 ° C. for 24 hours to prepare a composition for polymer electrolyte membrane formation.

The prepared polymer electrolyte membrane-forming composition was applied to a polytetrafluoroethylene film by a doctor blade method and then dried to form a polymer electrolyte layer. The polymer electrolyte layer was separated from the polytetrafluoroethylene film to prepare a polymer electrolyte membrane.

(Example 2)

A commercially available 5 wt% Nafion / H ₂ O / 2-propanol (Solution Technology Inc., EW = 1,100) solution was stirred at room temperature and evaporated under reduced pressure, and then dimethylacetamide (DMAc) at a concentration of 10 wt%. ) And mechanical stirring at 100 ° C. for 24 hours to prepare a cation exchange resin solution (10 wt% Nafion / DMF) with hydrogen ion conductivity. 3 parts by weight of an inorganic additive of phosphotungstic acid supported on montmorillonite was further dispersed with respect to 100 parts by weight of the cation exchange resin to prepare a composition for forming a polymer electrolyte membrane.

A polytetrafluoroethylene film was placed on one side of a stainless steel mesh having a diameter of 30 m of metal fibers and a distance of 87 m of fibers, and then subjected to a heat of 135 ° C. and a pressure of 300 kgf / cm ² . A polytetrafluoroethylene film was formed in which irregularities were regularly formed on cotton.

The prepared polymer electrolyte membrane-forming composition was coated on a patterned polytetrafluoroethylene film by a doctor blade method and dried to form a polymer electrolyte layer. The polymer electrolyte layer was separated from the polytetrafluoroethylene film to prepare a polymer electrolyte membrane.

(Comparative Example 1)

A commercially available 5 wt% Nafion / H ₂ O / 2-propanol (Solution Technology Inc., EW = 1,100) solution was stirred at room temperature and evaporated under reduced pressure, and then dimethylacetamide (DMAc) at a concentration of 10 wt%. ) Was added and mechanically stirred at 100 ° C. for 24 hours to prepare a composition for polymer electrolyte membrane formation.

The polymer electrolyte membrane-forming composition prepared above was applied to a glass substrate by a doctor blade method and then dried to form a polymer electrolyte layer. The polymer electrolyte layer was separated from the glass substrate to prepare a polymer electrolyte membrane.

(Comparative Example 2)

A commercially available 5 wt% Nafion / H ₂ O / 2-propanol (Solution Technology Inc., EW = 1,100) solution was stirred at room temperature and evaporated under reduced pressure, and then dimethylacetamide (DMAc) at a concentration of 10 wt%. ) And mechanical stirring at 100 ° C. for 24 hours to prepare a cation exchange resin solution (10 wt% Nafion / DMF) with hydrogen ion conductivity. 3 parts by weight of an inorganic additive of phosphotungstic acid supported on montmorillonite was further dispersed with respect to 100 parts by weight of the cation exchange resin to prepare a composition for forming a polymer electrolyte membrane.

The polymer electrolyte membrane-forming composition prepared above was applied to a glass substrate by a doctor blade method and then dried to form a polymer electrolyte layer. The polymer electrolyte layer was separated from the glass substrate to prepare a polymer electrolyte membrane.

The prepared polymer electrolyte membrane was placed on one side of a stainless steel mesh having a diameter of metal fiber of 30 mu m and a distance between the fibers of 87 mu m, and then subjected to 135 ° C heat and 300 kgf / cm ² pressure. A polymer electrolyte membrane was formed in which irregularities were regularly formed on cotton.

(Example 3)

Aqueous dispersion of 10 wt% Nafion (Nafion ^® , manufactured by Dupont) in 3.0 g of Pt black (Hispec ^® 1000, manufactured by Johnson Matthey) and Pt / Ru black (Hispec ^® 6000, manufactured by Johnson Matthey) in 3 ml of isopropyl alcohol 4.5 g was added dropwise, followed by mechanical stirring to prepare a composition for forming a catalyst layer.

The composition for forming the catalyst layer was coated on one surface of carbon paper with an area of 5 × ⁵ cm ² and a thickness of 50 mm to prepare an electrode. Thereafter, two electrodes were manufactured in the same manner, and used as a cathode electrode and an anode electrode, respectively.

A membrane-electrode assembly was prepared by placing the polymer electrolyte membrane prepared in Example 2 between the cathode electrode and the anode electrode and performing heat treatment at 110 ° C.

The prepared membrane-electrode assembly was inserted between two gaskets, and then inserted into two separators having a predetermined gas flow channel and cooling channel, and pressed between copper end plates to prepare a unit cell. .

(Comparative Example 3)

A single cell was manufactured by the same method as Example 3, except that the polymer electrolyte membrane prepared in Comparative Example 2 was used.

The surfaces of the polymer electrolyte membranes prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were observed.

As a result, the surface of the polymer electrolyte membranes of Examples 1 and 2 produced by the manufacturing method of the present invention was smooth, but in Comparative Examples 1 and 2, the surface of the polymer electrolyte membrane was not smooth due to the damage occurring in the peeling process and the pattern forming process. Did.

In addition, 1M methanol solution was used as the anode fuel for the cells prepared in Example 3 and Comparative Example 3, and air was injected into the cathode to observe voltage-current characteristics at 70 degrees.

As a result of the measurement, the fuel cell of Example 3 using the polymer electrolyte membrane prepared using the patterned release film was superior to the unit cell of Comparative Example 3 using the polymer electrolyte membrane subjected to the patterning process after formation of the electrolyte membrane on the glass substrate. The power density is shown. This result is because in the case of Comparative Example 3, the polymer electrolyte membrane was damaged in the peeling process and the pattern forming process from the glass substrate during the production of the polymer electrolyte membrane, and thus the uniform thickness and pattern were not formed.

The polymer electrolyte membrane production method of the present invention was able to minimize damage to the polymer electrolyte membrane and to easily form a pattern on the polymer electrolyte membrane. In addition, the prepared polymer electrolyte membrane may have a uniform thickness and pattern to improve the performance of the fuel cell.

Claims (7)

The polymer electrolyte membrane-forming composition is applied to a release film to form a polymer electrolyte layer, And separating the polymer electrolyte layer from the release film to produce a polymer electrolyte membrane. The method of claim 1, The polymer electrolyte membrane-forming composition is a method for producing a polymer electrolyte membrane for a fuel cell comprising a cation exchange resin. The method of claim 2, And said cation exchange resin is a polymer resin having a cation exchange group selected from the group consisting of sulfonic acid group, carboxylic acid group, phosphoric acid group, phosphonic acid group and derivatives thereof in the side chain. The method of claim 1, The polymer electrolyte membrane-forming composition further comprises an inorganic additive. The method of claim 1, The polymer electrolyte membrane-forming composition is a method for producing a polymer electrolyte membrane for a fuel cell having a viscosity of 2000 to 10000cps. The method of claim 1, The release film may be polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkylvinylether copolymer, ethylene / tetrafluoroethylene, polyvinylidene fluoride, poly A method for producing a polymer electrolyte membrane for a fuel cell, comprising one or more selected from the group consisting of mead, polyethylene, polypropylene, polyethylene terephthalate and polyester.  The method of claim 1, The release film is a method of producing a polymer electrolyte membrane for a fuel cell having a pattern.

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