JP5332212B2 - Electrolyte membrane-catalyst layer assembly with gasket, electrolyte membrane-electrode assembly with gasket and solid polymer fuel cell using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrolyte membrane-catalyst layer assembly with a gasket capable of preventing certainly gas leak and an electrolyte membrane-electrode assembly with a gasket using the same, and a solid polymer fuel cell. <P>SOLUTION: The electrolyte membrane-electrode assembly with a gasket includes a solid polymer electrolyte membrane 2, a catalyst layer 3 formed on both faces of the electrolyte membrane 2, and a frame shape gasket 4 which is installed on the outer periphery part 31 of each catalyst layer 3, and has an aperture 41 in the center. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an electrolyte membrane-catalyst layer assembly with a gasket, an electrolyte membrane-electrode assembly with a gasket using the same, and a polymer electrolyte fuel cell.

  A fuel cell is a cell in which electrodes are arranged on both sides of an electrolyte and generates electricity by an electrochemical reaction between hydrogen and oxygen, and only water is generated during power generation. Thus, unlike the conventional internal combustion engine, it is expected to spread as a next-generation clean energy system because it does not generate environmental load gas such as carbon dioxide. In particular, the polymer electrolyte fuel cell has a low operating temperature and low electrolyte resistance. In addition, it uses a highly active catalyst, so it can obtain high output even in a small size. Is expected to be put to practical use.

This polymer electrolyte fuel cell uses a solid polymer electrolyte membrane having proton conductivity, and a catalyst layer and a gas diffusion layer are sequentially laminated on both surfaces of the electrolyte membrane. And it has the structure which has arrange | positioned the gasket so that the circumference | surroundings of the electrode which consists of this catalyst layer and a gas diffusion layer may be enclosed, and also this was pinched | interposed with the separator (for example, refer patent document 1). In order to generate power in this polymer electrolyte fuel cell, a fuel gas such as hydrogen is supplied to one electrode and an oxidant gas such as oxygen is supplied to the other electrode.
JP-A-9-274926

  However, in the polymer electrolyte fuel cell, a gap is formed between the gasket and the electrode, and the electrolyte membrane corresponding to the gap is not pressed by either the electrode or the gasket. ing. For this reason, when an electrolyte membrane repeats a wet state and a dry state, and expansion and contraction are repeated, stress is generated in the electrolyte membrane, resulting in fatigue, and the electrolyte membrane may be damaged. As a result, a gas leak occurs through the damaged portion of the electrolyte membrane, causing a problem that the fuel gas and the oxidant gas are mixed.

  Accordingly, the present invention provides an electrolyte membrane-catalyst layer assembly with a gasket capable of reliably preventing gas leakage, an electrolyte membrane-electrode assembly with a gasket using the same, and a polymer electrolyte fuel cell. Let it be an issue.

  The gasket-attached electrolyte membrane-catalyst layer assembly according to the present invention is made to solve the above-mentioned problems, and includes a solid polymer electrolyte membrane, catalyst layers formed on both surfaces of the electrolyte membrane, and A frame-like gasket having an opening at the center, which is installed on the outer peripheral edge of each catalyst layer.

  The electrolyte membrane-catalyst layer assembly with a gasket thus configured usually forms a gas diffusion layer on the catalyst layer exposed from the opening of the gasket to produce an electrolyte membrane-electrode assembly with a gasket. By installing a separator so as to sandwich the gasket-attached electrolyte membrane-electrode assembly, it is used as a polymer electrolyte fuel cell. This fuel cell can prevent gas leakage even if the electrolyte membrane is damaged by repeated expansion and contraction. That is, in the polymer electrolyte fuel cell using the gasket-attached electrolyte membrane-catalyst layer assembly having the above-described configuration, the gasket is installed on the outer peripheral edge of the catalyst layer. Since the damaged portion of the electrolyte membrane is located outside the catalyst layer, that is, outside the gasket, the fuel gas or oxidant gas supplied from the gas flow path of the separator is blocked by the gasket until the damaged portion of the electrolyte membrane. As a result, mixing of the oxidant gas and the fuel gas can be prevented.

  The gasket-attached electrolyte membrane-catalyst layer assembly can take various configurations. For example, the catalyst layer has an outer shape that matches the electrolyte membrane, and is formed on both surfaces of the electrolyte membrane. It is preferable. In this way, by making the electrolyte membrane the same size and shape as the catalyst layer, it is possible to minimize the use of the electrolyte membrane / catalyst layer that does not contribute to power generation.

  The gasket preferably has an adhesive layer on one side facing the catalyst layer. By comprising in this way, since a gasket and an electrolyte membrane-catalyst layer assembly can be handled as one body, handling becomes easy when installing a gas diffusion layer and a separator in a post process.

  Each gasket is formed to be slightly larger than the electrolyte membrane-catalyst layer assembly including the electrolyte membrane and the catalyst layer, and the adhesive layers adhere to each other outside the electrolyte membrane-catalyst layer assembly. Preferably it is. Thus, by bonding the adhesive layers together, the gasket can be more firmly bonded to the electrolyte membrane-catalyst layer assembly.

  Moreover, it is preferable that the said gasket has a heat resistant layer in the other surface side. As described above, the gasket-attached electrolyte membrane-catalyst layer assembly is usually used as a polymer electrolyte fuel cell by installing a gas diffusion layer and a separator, but this fuel cell has a high temperature separator during power generation. Therefore, it is preferable from the viewpoint of durability that a heat-resistant layer is formed on the surface of the gasket in contact with the separator to provide heat resistance.

  Moreover, it is preferable that the said gasket has elasticity. By giving elasticity to the gasket in this way, for example, by installing a gas diffusion layer thinner than the thickness of the gasket and pressing the gasket with a separator so that the gasket has the same thickness as the gas diffusion layer, more gaskets can be obtained. Can be adhered to the electrolyte membrane-catalyst layer assembly.

  In addition, an electrolyte membrane-electrode assembly with a gasket according to the present invention is made to solve the above problems, and any one of the above-described electrolyte membrane-catalyst layer assembly with a gasket and an opening of the catalyst layer are provided. A gas diffusion layer formed on the catalyst layer in the section to a thickness equal to or less than the thickness of the gasket.

  The polymer electrolyte fuel cell according to the present invention is made to solve the above-described problem, and sandwiches the electrolyte membrane-electrode assembly with gasket and the electrolyte membrane-electrode assembly with gasket. And a separator in which a gas flow path is formed in a region facing the gas diffusion layer.

  ADVANTAGE OF THE INVENTION According to this invention, the electrolyte membrane-catalyst layer assembly with a gasket which can prevent gas leak reliably, the electrolyte membrane-electrode assembly with a gasket using the same, and a polymer electrolyte fuel cell are provided. it can.

  Hereinafter, embodiments of an electrolyte membrane-catalyst layer assembly with gasket, an electrolyte membrane-electrode assembly with gasket, and a polymer electrolyte fuel cell according to the present invention will be described with reference to the drawings. FIG. 1 is a front sectional view of a polymer electrolyte fuel cell according to this embodiment, FIG. 2 is a plan view of the polymer electrolyte fuel cell according to this embodiment, and FIG. 3 is an outside of an electrolyte membrane-electrode assembly with a gasket. It is an expanded front sectional view showing details of a peripheral part. In FIG. 2, the description of the separator is omitted for easy understanding.

  As shown in FIGS. 1 and 2, the polymer electrolyte fuel cell 1 includes an electrolyte membrane 2 having a rectangular shape in plan view, and a plan view that is slightly smaller than the electrolyte membrane 2 on the upper and lower surfaces of the electrolyte membrane 2. A rectangular catalyst layer 3 is formed. A structure in which the catalyst layer 3 is formed on both surfaces of the electrolyte membrane 2 is referred to as an electrolyte membrane-catalyst layer assembly 10. Thus, since the catalyst layer 3 is formed slightly smaller than the electrolyte membrane 2, the catalyst layer 3 is not formed on the outer peripheral edge 21 of the electrolyte membrane 2. In addition, it is preferable that the distance C (refer FIG. 3) from the outer periphery of the electrolyte membrane 2 to the outer periphery of the catalyst layer 3 is 0-5 mm.

  And the frame-shaped gasket 4 which has the opening part 41 in the center is installed in the upper surface and lower surface of this electrolyte membrane-catalyst layer assembly 10, respectively. The gasket 4 is composed of a gasket body 40 having elasticity, and an adhesive layer 42 is formed on a surface (one surface) facing the electrolyte membrane-catalyst layer assembly 10 of the gasket body 40, and the other surface, That is, the heat-resistant layer 43 is formed on the surface (the other surface) facing the separator 6 described later. The thickness of the gasket 4 itself is not particularly limited, but is preferably 100 to 500 μm. Among these, the film thickness of the adhesive layer 42 is preferably 5 to 100 μm. The film thickness is preferably 5 to 100 μm. In a state where the gasket 4 is installed in the electrolyte membrane-catalyst layer assembly 10, the catalyst layer 3 is exposed from the opening 41 of the gasket 4 except for the outer peripheral edge 31, and the outer peripheral edge of the catalyst layer 3. The gasket 4 is bonded onto the outer peripheral edge portion 31 of the electrolyte 31 and the electrolyte 2. In addition, it is preferable that the distance B (refer FIG. 3) from the outer periphery of the catalyst layer 3 to the inner periphery of the gasket 4 shall be 1-5 mm. Further, since the gasket 4 is formed to be slightly larger than the electrolyte membrane 2, the outer peripheral edge portions 45 of the gaskets 4 protruding from the electrolyte membrane 2 are bonded to each other outside the electrolyte membrane 2. The distance D (see FIG. 3) from the outer peripheral edge of the gasket 4 to the outer peripheral edge of the electrolyte membrane 2 is preferably 10 to 100 mm. As described above, the electrolyte membrane-catalyst layer assembly 10 provided with the gasket 4 corresponds to the gasket-attached electrolyte membrane-catalyst layer assembly of the present invention.

  A gas diffusion layer 5 having a rectangular shape in plan view is disposed on the catalyst layer 3 exposed from the opening 41 of the gasket 4. The thickness of the gas diffusion layer 5 is the same as the thickness of the gasket 4 or about 20 to 200 μm thinner than the thickness of the gasket 4. The distance A (see FIG. 3) from the outer peripheral edge of the gas diffusion layer 5 to the inner peripheral edge of the gasket 4 is preferably 0 to 5 mm. Thus, the gas diffusion layer 5 is formed on the catalyst layer 3 to constitute the electrode E, and the electrode E formed on both surfaces of the electrolyte membrane 2 is called an electrolyte membrane-electrode assembly 20. In addition, like this embodiment, what the gasket 4 was installed in the electrolyte membrane-electrode assembly 20 is equivalent to the electrolyte membrane-electrode assembly with a gasket of this invention.

  Separators 6 are installed on the upper and lower surfaces of the electrolyte membrane-electrode assembly with gasket so as to sandwich the electrolyte membrane-electrode assembly with gasket. In the separator 6, a gas flow path 71 is formed in a region facing the gas diffusion layer 5.

  Next, the material of each component of the polymer electrolyte fuel cell 1 configured as described above will be described.

  The electrolyte membrane 2 is formed, for example, by applying a solution containing a hydrogen ion conductive polymer electrolyte on a substrate and drying it. Examples of the hydrogen ion conductive polymer electrolyte include a perfluorosulfonic acid-based fluorine ion exchange resin, more specifically, a perfluorocarbonsulfonic acid-based resin in which the C—H bond of a hydrocarbon ion-exchange membrane is substituted with fluorine. Examples include polymers (PFS polymers). By introducing a fluorine atom having high electronegativity, it is chemically very stable, the dissociation degree of the sulfonic acid group is high, and high ion conductivity can be realized. Specific examples of such a hydrogen ion conductive polymer electrolyte include “Nafion” (registered trademark) manufactured by DuPont, “Flemion” (registered trademark) manufactured by Asahi Glass Co., Ltd., and “Aciplex” manufactured by Asahi Kasei Corporation. ”(Registered trademark),“ Gore Select ”(registered trademark) manufactured by Gore, and the like. The concentration of the hydrogen ion conductive polymer electrolyte contained in the hydrogen ion conductive polymer electrolyte-containing solution is usually about 5 to 60% by weight, preferably about 20 to 40% by weight. In addition, the film thickness of the electrolyte membrane 2 is about 20-250 micrometers normally, Preferably it is about 20-80 micrometers.

  The catalyst layer 3 is a known platinum-containing catalyst layer (cathode catalyst and anode catalyst). Specifically, the catalyst layer 3 contains carbon particles supporting catalyst particles and a hydrogen ion conductive polymer electrolyte. Examples of the catalyst particles include platinum and platinum compounds. Examples of the platinum compound include an alloy of platinum and at least one metal selected from the group consisting of ruthenium, palladium, nickel, molybdenum, iridium, iron and the like. In general, the catalyst particles contained in the cathode catalyst layer are platinum, and the catalyst particles contained in the anode catalyst layer are an alloy of the metal and platinum. Moreover, as a hydrogen ion conductive polymer electrolyte, the same material as what is used for the electrolyte membrane 2 mentioned above can be used.

  The gasket 4 includes a gasket body 40, an adhesive layer 42, and a heat resistant layer 43. As the gasket body 40, a fibrous sheet, a porous sheet, paper, or the like can be used. As a fiber or resin constituting the fibrous sheet and the porous sheet, heat resistance, acid resistance, hydrolysis resistance and flexibility are required. As the fiber, for example, natural fibers such as cellulose, wool, silk, cotton, hemp, etc., or glass fibers, carbon fibers, rock fibers, or well-known heat resistant synthetic resins such as polyester, polyamide, polyimide, polymethylpentene, etc. An unstretched sheet made of the above-described chemical fiber, or the above heat-resistant synthetic resin, or a stretched sheet made porous. Examples of the paper include craft paper, crepe paper, high-quality paper, coated paper, and Japanese paper. For example, acetate fiber cloth, polyester nonwoven fabric, paper, or a composite base material thereof can be used. Further, as the material of the adhesive layer 42, a synthetic resin adhesive can be used, and for example, acrylic, rubber, and silicone can be used. More specifically, acrylic ester copolymers, methacrylic ester copolymers, natural rubber (NR), synthetic natural rubber (IR), styrene-butadiene rubber (SBR), polyisobutylene (PIB), butyl rubber (IIR) And silicon rubber. Examples of the material for the heat resistant layer 43 include polyester, polyimide, polyamide, polymethylpentene, polyether ether ketone, and the like.

  As the gas diffusion layer 5, various types of gas diffusion layers constituting a fuel electrode and an air electrode can be used. In order to efficiently supply fuel gas and oxidant gas as fuel to the catalyst layer 3, the gas diffusion layer 5 is porous. It is made of a conductive substrate. Examples of the porous conductive substrate include carbon paper and carbon cloth.

  The separator 6 may be any known conductive plate that is known and stable even in the environment within the fuel cell. In general, a carbon plate in which a gas flow path 71 is formed is used. In addition, the separator 6 is made of a metal such as stainless steel, and a film made of a conductive material such as chromium, a platinum group metal or oxide thereof, or a conductive polymer is formed on the surface of the metal. It is also possible to use a metal having a metal surface plated with a material such as silver, a platinum group composite oxide, or chromium nitride.

  Next, a method for producing the above-described polymer electrolyte fuel cell 1 will be described with reference to the drawings. FIG. 4 is an explanatory view showing a method for producing the polymer electrolyte fuel cell 1 according to this embodiment.

  First, the electrolyte membrane 2 made of the above-described material is prepared, and the catalyst layer forming transfer sheet 8 is placed on both surfaces of the electrolyte membrane 2 (FIG. 4A). Here, the transfer sheet 8 for forming a catalyst layer is one in which the transferred catalyst layer 3 is formed on a transfer substrate 81. The production method of the catalyst layer forming transfer sheet 8 will be described. First, the above-described carbon particles supporting the catalyst particles and the hydrogen ion conductive polymer electrolyte are mixed and dispersed in an appropriate solvent to prepare a catalyst paste. . Then, the catalyst paste is applied onto the transfer substrate 81 through a release layer as necessary in accordance with a known method so that the formed catalyst layer 3 has a desired film thickness. At this time, the catalyst paste is applied to the transfer substrate 81 so that the catalyst layer 3 has a shape slightly smaller than the electrolyte membrane 2. Examples of the method for applying the catalyst paste include known coating methods such as screen printing, spray coating, die coating, and knife coating. Examples of the solvent include various alcohols, various ethers, various dialkyl sulfoxides, water, or a mixture thereof. Of these, alcohols are preferable. Examples of alcohols include monohydric alcohols having 1 to 4 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and tert-butanol, and various polyhydric alcohols. Examples of the transfer base material 81 include polyimide, polyethylene terephthalate, polyparvanic acid aramid, polyamide (nylon), polysulfone, polyethersulfone, polyphenylene sulfide, polyether ether ketone, polyetherimide, polyarylate, and polyethylene naphthalate. And the like. In addition, heat resistance of ethylene tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroperfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), etc. Fluorine resin can also be used. Further, the transfer substrate 81 may be coated paper such as art paper, coated paper, lightweight coated paper, non-coated paper such as notebook paper, copy paper, etc. in addition to the polymer film. The thickness of the transfer substrate 81 is usually about 6 to 100 μm, preferably about 10 to 30 μm, from the viewpoints of handleability and economy. Therefore, the transfer substrate 81 is preferably a polymer film that is inexpensive and easily available, and more preferably polyethylene terephthalate.

  Then, after applying the catalyst paste, the catalyst layer 3 is formed on the transfer substrate 81 by drying at a predetermined temperature and time. A drying temperature is about 40-100 degreeC normally, Preferably it is about 60-80 degreeC. Although depending on the drying temperature, the drying time is usually about 5 minutes to 2 hours, preferably about 10 minutes to 1 hour.

  Continuing the description of the method for producing a polymer electrolyte fuel cell, the transfer sheet 8 for forming a catalyst layer produced as described above is arranged so that the catalyst layer 3 faces the electrolyte membrane 1 (FIG. 4 (a)). Then, a heat press is applied from the back side of the transfer sheet 8 to transfer the catalyst layer 3 to the electrolyte membrane 2, and the transfer substrate 81 of the transfer sheet 8 is peeled off (FIG. 4B). In consideration of workability, it is preferable to simultaneously laminate the catalyst layer 3 on both surfaces of the electrolyte membrane 2, but the catalyst layer 3 can also be formed on each side. The pressure level of the heating press is usually about 0.5 to 20 MPa, preferably about 1 to 10 MPa in order to avoid transfer failure. Further, it is preferable to heat the pressing surface during this pressing operation in order to avoid transfer failure. The heating temperature is usually 200 ° C. or lower, preferably 150 ° C. or lower, in order to avoid damage or deformation of the electrolyte membrane 2. Thus, the electrolyte membrane-catalyst layer assembly 10 is formed by forming the catalyst layers 3 on both surfaces of the electrolyte membrane 2. At this time, since the catalyst layer 3 is slightly smaller than the electrolyte membrane 2, the outer peripheral edge 21 of the electrolyte membrane 2 is exposed.

  Next, the gasket 4 is attached to the electrolyte membrane-catalyst layer assembly 10 thus formed (FIG. 4C). More specifically, the gaskets 4 are respectively disposed on the upper surface and the lower surface of the electrolyte membrane-catalyst layer assembly 10. At this time, the gaskets 4 are arranged so that the adhesive layers 42 of the gaskets 4 face each other. The gasket 4 is bonded onto the outer peripheral edge 31 of the catalyst layer 3 and the outer peripheral edge 21 of the electrolyte membrane 2 so that the catalyst layer 3 is exposed from the opening 41 of the gasket 4 except for the outer peripheral edge 31.

  Subsequently, the gas diffusion layer 5 is laminated on the catalyst layer 3 exposed from the opening 41 of the above-described electrolyte membrane-catalyst layer assembly with gasket by thermocompression bonding, and the electrolyte membrane-electrode assembly with gasket is formed. Is completed (FIG. 4D). And the separator 6 is installed so that this electrolyte membrane electrode assembly with a gasket may be clamped. At this time, the gas flow path 61 of the separator 6 faces the gas diffusion layer 5. Thus, the polymer electrolyte fuel cell 1 is completed (FIG. 4E).

  As described above, in the present embodiment, the outer peripheral edge portion 21 of the electrolyte membrane 2 is restrained by the gasket 4, so that the expansion / contraction of the electrolyte membrane 2 can be suppressed. Breakage can be prevented. Even if the outer peripheral edge 21 of the electrolyte membrane 2 is damaged, the gas supplied from the gas flow path 61 of the separator 6 because the gasket 4 is installed on the outer peripheral edge 31 of the catalyst layer 3. Ensures that the fuel gas supplied to the anode electrode and the oxidant gas supplied to the cathode electrode are mixed without being obstructed by the gasket 4 and reaching the damaged portion at the outer peripheral edge 21 of the electrolyte membrane 2. Can be prevented.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention. For example, in the above embodiment, the gasket 4 is formed to be slightly larger than the electrolyte membrane-catalyst layer assembly 10, but the present invention is not particularly limited thereto, and as shown in FIG. It is also possible to form the gasket 4 approximately the same size as the catalyst layer 3 and install the gasket 4 only on the outer peripheral edge 31 of the catalyst layer 3.

  Moreover, in the said embodiment, although the catalyst layer 3 is formed slightly smaller than the electrolyte membrane 2, it is not specifically limited to this, The catalyst layer 3 is formed in the same magnitude | size as the electrolyte membrane 2. You can also. That is, as shown in FIG. 7, the electrolyte membrane 2 can be formed to have the same size and the same shape as the catalyst layer 3 so that the catalyst layer 3 covers both surfaces of the electrolyte membrane 2. Thus, by omitting the outer peripheral edge 21 of the electrolyte membrane 2 that has not contributed to power generation, it is possible to suppress the use of the generally expensive electrolyte membrane 2 and to reduce the cost.

  Moreover, in the said embodiment, although the gasket 4 forms the adhesive layer 42 in the one surface of the gasket main body 42 which has elasticity, and forms the heat resistant layer 43 in the other surface, the adhesive layer 42 and the heat resistant layer 43 are formed. However, it is also possible to adopt a configuration with only the gasket main body 42.

  In the above embodiment, the electrolyte membrane 2, the catalyst layer 3, and the gas diffusion layer 5 constituting the solid polymer fuel cell 1 are all described as a rectangular shape in plan view, but the shape is not particularly limited, For example, it can be a circular shape in plan view.

  The present invention will be described more specifically with reference to the following examples and comparative examples. In addition, this invention is not limited to the following Example.

Example 1
As the electrolyte membrane 2, NRE212CS (manufactured by Dupont) having a film thickness of 53 μm cut to a size of 63 × 63 mm was used.

Next, a catalyst-forming transfer sheet 8 was produced in the following manner. First, 2 g of platinum catalyst-supported carbon (platinum supported amount: 45.7 wt%, manufactured by Tanaka Kikinzoku Co., Ltd., TEC10E50E), 1 g of 1-butanol, 10 g of 3-butanol, 20 g of a fluororesin (5 wt% Nafion binder, manufactured by DuPont) and 6 g of water was added, and these were stirred and mixed with a disperser to prepare an ink composition for forming a catalyst. Next, the ink was applied to a polyester film (Toray, X44, 25 μm) so that the weight of platinum after drying the catalyst layer was 0.4 mg / cm ² to prepare a transfer sheet 8 for forming a catalyst.

  The catalyst-forming transfer sheet 8 produced as described above was cut into a size of 60 × 60 mm, and placed on both surfaces of the electrolyte membrane 2 so that the catalyst layer 3 was directed to the electrolyte membrane 2 side. The catalyst layer 3 was formed on both surfaces of the electrolyte membrane 2 by hot pressing under conditions of 135 ° C., 5.0 MPa, 150 seconds, and the electrolyte membrane-catalyst layer assembly 10 was produced. The catalyst layer 3 has a thickness of 20 μm.

  Subsequently, a highly insulating tape (manufactured by Nitto Denko Corporation, No. 341) was used as the gasket 4. This highly insulating tape is composed of a gasket body 40 made of a polyester nonwoven fabric having a thickness of 375 μm, an adhesive layer 42 made of an acrylic resin having a thickness of 50 μm, and a heat-resistant layer 43 made of a polyester film having a thickness of 25 μm. Yes. The gasket 4 was cut into a size of 80 × 80 mm, and an opening 41 having a size of 50 × 50 mm was formed at the center. Then, the gasket 4 is bonded to the electrolyte membrane-catalyst layer assembly 10 by placing the gasket 4 in the center on both surfaces of the electrolyte membrane-catalyst layer assembly 10 and pressing the gasket 4 to bond the gasket 4 to the electrolyte membrane-catalyst layer assembly 10. The body was made.

  Subsequently, on the catalyst layer 3 exposed from the opening 41, a carbon paper (TGP-H-090, manufactured by Toray Industries, Inc., thickness 280 μm) cut into a size of 49 × 49 mm as the gas diffusion layer 5 is used. ) To form a gasketed electrolyte membrane-electrode assembly.

(Comparative Example 1)
As the electrolyte membrane 2, NRE212CS (manufactured by Dupont) having a film thickness of 53 μm cut to a size of 80 × 80 mm was used.

  Next, the same catalyst-forming transfer sheet 8 as in the first embodiment is cut into a size of 50 × 50 mm, and the center is aligned so that the catalyst layer 3 faces the electrolyte membrane 2 side on each side of the electrolyte membrane 2. Arranged. The catalyst layer 3 was formed on both surfaces of the electrolyte membrane 2 by hot pressing under conditions of 135 ° C., 5.0 MPa, 150 seconds, and the electrolyte membrane-catalyst layer assembly 10 was produced. The catalyst layer 3 has a thickness of 20 μm.

  Subsequently, as the gasket, polyethylene naphthalate having a thickness of 100 μm was used as a gasket body, and a silicon rubber layer having a thickness of 100 μm was formed on the upper surface and the lower surface thereof. This gasket was cut into a size of 80 × 80 mm, and an opening 41 having a size of 51 × 51 mm was formed at the center. On the catalyst layer 3 exposed from the opening 41, a carbon paper (TGP-H-090, thickness: 280 μm) cut into a size of 49 × 49 mm is laminated as the gas diffusion layer 5. Then, an electrolyte membrane-electrode assembly with a gasket was formed. As shown in FIG. 6, the gasket is installed on the outer peripheral edge of the electrolyte membrane 2, and a gap is formed between the gasket and the catalyst layer.

(Evaluation method)
About the electrolyte membrane-electrode assembly with a gasket of Example 1 and Comparative Example 1, the separator 6 was installed and the polymer electrolyte fuel cell was produced, respectively, and the load fluctuation cycle test was implemented. The measurement conditions at this time were a cell temperature of 80 ° C., a fuel utilization rate of 70%, an oxidant utilization rate of 40%, and a humidification temperature of 50 ° C. As a result of the current voltage measurement evaluation, the durability time of the fuel cell of Example 1 was 1000 hours, and no damage to the electrolyte membrane was observed after the evaluation. On the other hand, the durability time of the fuel cell of Comparative Example 1 was 300 hours. After the evaluation for 300 hours, damage to the electrolyte membrane 2 was visually confirmed. Further, as a result of measuring the leakage current amount after the load fluctuation cycle test, the leakage current amount of the fuel battery cell of Example 1 was 1 mA / cm ² or less, whereas the leakage current amount of the fuel battery cell of Comparative Example 1 was 20 mA / cm ^2. Gas leakage due to breakage of the electrolyte membrane was observed at cm ² or more.

  As described above, in the polymer electrolyte fuel cell of Example 1, since the durability time is increased, it is understood that the problem of the electrolyte membrane breakage was solved by using the polymer electrolyte fuel cell of the present invention. .

1 is a front sectional view showing an embodiment of a polymer electrolyte fuel cell according to the present invention. 1 is a plan view showing an embodiment of a polymer electrolyte fuel cell according to the present invention. It is an expanded front sectional view which shows the detail of the outer periphery part of the electrolyte membrane-electrode assembly with a gasket which concerns on this embodiment. It is explanatory drawing which shows the manufacturing method of the polymer electrolyte fuel cell which concerns on this embodiment. It is front sectional drawing which shows other embodiment of the polymer electrolyte fuel cell which concerns on this invention. 6 is a front cross-sectional view showing an electrolyte membrane-electrode assembly with a gasket according to Comparative Example 1. FIG. It is front sectional drawing which shows other embodiment of the solid oxide fuel cell which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid polymer fuel cell 2 Electrolyte membrane 21 Outer peripheral edge part 3 of electrolyte membrane Catalyst layer 31 Outer peripheral edge part 4 of catalyst layer Gasket 40 Gasket body 41 Opening part 42 Adhesive layer 43 Heat-resistant layer 45 Outer peripheral edge part 5 of gasket Gas diffusion Layer 6 Separator 10 Electrolyte membrane-catalyst layer assembly 20 Electrolyte membrane-electrode assembly

Claims (8)

A solid polymer electrolyte membrane;
Catalyst layers respectively formed on both surfaces of the electrolyte membrane;
A frame-like gasket having an opening in the center, directly installed on the outer peripheral edge of each catalyst layer;
An electrolyte membrane-catalyst layer assembly with a gasket, comprising: The catalyst layer, the electrolyte membrane and has an outer shape you meet, the are formed on the entire both surfaces of the electrolyte membrane, gasketed electrolyte membrane according to claim 1 - catalyst layer assembly.   The electrolyte membrane-catalyst layer assembly with gasket according to claim 1 or 2, wherein the gasket has an adhesive layer on one side facing the catalyst layer. The outer peripheral edge of each gasket is formed to be slightly larger than the electrolyte membrane-catalyst layer assembly composed of the electrolyte membrane and the catalyst layer, and the adhesive layers are formed outside the electrolyte membrane-catalyst layer assembly. The electrolyte membrane-catalyst layer assembly with gasket according to claim 3, wherein:   The gasket-attached electrolyte membrane-catalyst layer assembly according to any one of claims 1 to 4, wherein the gasket has a heat-resistant layer on the other surface side.   The electrolyte membrane-catalyst layer assembly with gasket according to any one of claims 1 to 5, wherein the gasket has elasticity. An electrolyte membrane-catalyst layer assembly with gasket according to any one of claims 1 to 6,
On the catalyst layer in the opening of the gasket , a gas diffusion layer formed to a thickness equal to or less than the thickness of the gasket;
An electrolyte membrane-electrode assembly with a gasket, comprising: An electrolyte membrane-electrode assembly with gasket according to claim 7,
A separator installed so as to sandwich the gasket-attached electrolyte membrane-electrode assembly, and a gas channel formed in a region facing the gas diffusion layer;
A solid polymer fuel cell comprising:

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