US20140017590A1 - Electrolyte membrane-electrode assembly for fuel cells, and method for producing same - Google Patents
Electrolyte membrane-electrode assembly for fuel cells, and method for producing same Download PDFInfo
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- US20140017590A1 US20140017590A1 US14/008,193 US201214008193A US2014017590A1 US 20140017590 A1 US20140017590 A1 US 20140017590A1 US 201214008193 A US201214008193 A US 201214008193A US 2014017590 A1 US2014017590 A1 US 2014017590A1
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- electrode
- resin
- frame member
- resin frame
- gas diffusion
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/1004—Fuel cells with solid electrolytes characterised by membrane-electrode assemblies [MEA]
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
- H01M8/0276—Sealing means characterised by their form
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0267—Collectors; Separators, e.g. bipolar separators; Interconnectors having heating or cooling means, e.g. heaters or coolant flow channels
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
- H01M8/0273—Sealing or supporting means around electrodes, matrices or membranes with sealing or supporting means in the form of a frame
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M2008/1095—Fuel cells with polymeric electrolytes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
- H01M8/0286—Processes for forming seals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Definitions
- the present invention relates to a fuel cell membrane electrode assembly (electrolyte membrane-electrode assembly for fuel cells), and a method of producing the fuel cell membrane electrode assembly.
- the fuel cell membrane electrode assembly includes a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane.
- Each of the first electrode and the second electrode includes an electrode catalyst layer and a gas diffusion layer.
- the outer size of the first electrode is smaller than the outer size of the second electrode.
- a solid polymer electrolyte fuel cell employs a solid polymer electrolyte membrane.
- the solid polymer electrolyte membrane is a polymer ion exchange membrane.
- the fuel cell includes a membrane electrode assembly (MEA) where an anode and a cathode are provided on both sides of the solid polymer electrolyte membrane.
- Each of the anode and the cathode includes a catalyst layer (electrode catalyst layer) and a gas diffusion layer (porous carbon).
- the membrane electrode assembly is sandwiched between separators (bipolar plates).
- a predetermined number of the fuel cells are stacked together to form a fuel cell stack.
- the fuel cell stack is mounted in a fuel cell electric vehicle as an in-vehicle fuel cell stack.
- the membrane electrode assembly has structure where components of the MEA have different sizes, i.e., the surface size (surface area) of one of diffusion layers is smaller than the surface size (surface area) of the solid polymer electrolyte membrane, and the surface size of the other of the gas diffusion layers is the same as the surface size of the solid polymer electrolyte membrane (a stepped-type MEA).
- a membrane electrode assembly disclosed in Japanese Laid-Open Patent Publication No. 2007-066766 (hereinafter referred to as conventional technique) includes an electrolyte membrane 1 , a cathode catalyst layer 2 a provided on one side of the electrolyte membrane 1 , an anode catalyst layer 2 b provided on the other surface of the electrolyte membrane 1 , and gas diffusion layers 3 a , 3 b provided on both sides of the electrolyte membrane 1 .
- the surface area of the gas diffusion layer 3 b of the anode is equal to the surface area of the electrolyte membrane 1 , and larger than the surface area of the gas diffusion layer 3 a of the cathode.
- a gasket structure body 4 is provided in an edge area of the membrane electrode assembly (MEA), and the outer end of the electrolyte membrane 1 adjacent to the gas diffusion layer 3 a is joined to the gasket structure body 4 through an adhesive layer 5 .
- the MEA and the gasket structure body 4 are fixed to the outer marginal portion of the electrolyte membrane 1 exposed to the outside from the gas diffusion layer 3 a , through the adhesive layer 5 only. Therefore, the strength of joining the MEA and the gasket structure body 4 is low, and the desired strength cannot be obtained.
- the present invention has been made to solve the problem of this type, and an object of the present invention is to provide a fuel cell membrane electrode assembly and a method of producing the fuel cell membrane electrode assembly in which it is possible to firmly and easily join a resin frame member around a solid polymer electrolyte membrane, and suitably suppress deformation of the resin frame member.
- the present invention relates to a fuel cell membrane electrode assembly, and a method of producing the fuel cell membrane electrode assembly.
- the fuel cell membrane electrode assembly includes a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane.
- Each of the first electrode and the second electrode includes an electrode catalyst layer and a gas diffusion layer.
- An outer size of the first electrode is smaller than an outer size of the second electrode.
- the membrane electrode assembly includes a resin frame member provided around the solid polymer electrolyte membrane and an impregnation portion for joining the resin frame member and at least one of an outer marginal portion of the first electrode and an outer marginal portion of the second electrode together.
- the production method includes the steps of forming the first electrode and the second electrode on both sides of the solid polymer electrolyte membrane, forming a resin frame member, and overlapping an outer marginal portion of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member around the solid polymer electrolyte membrane.
- the production method includes the steps of overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode, forming the electrode catalyst layers on both surfaces of the solid polymer electrolyte membrane, and combining the gas diffusion layer of the first electrode joined to the resin frame member and the gas diffusion layer of the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
- the production method includes the steps of overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode, forming the electrode catalyst layer on the gas diffusion layer of the second electrode and forming the electrode catalyst layer of the first electrode on one side of the solid polymer electrolyte membrane, and combining the first electrode joined to the resin frame member and the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
- the impregnation portion joining the resin frame member and the at least one of the outer marginal portion of the first electrode and the outer marginal portion of the second electrode together is provided.
- the joining strength for joining the resin frame member to at least one of the first electrode and the second electrode is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- the resin frame member is joined only to the first electrode. Therefore, the portion of the resin frame member where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of the resin frame member. Thus, it is possible to firmly and easily join the resin frame member around the solid polymer electrolyte membrane, and suitably suppress deformation of the resin frame member.
- the outer ends of the gas diffusion layers of the first electrode and the second electrode and the resin frame member are impregnated with resin to form the resin impregnation portion integrally.
- the joining strength for joining the resin frame member to the first electrode and the second electrode is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- the outer end of the gas diffusion of the second electrode and the resin frame member are impregnated with resin to form the resin impregnation portion integrally. Therefore, the portion of the resin frame member where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of the resin frame member. Further, since the resin impregnation portion is provided only at the second electrode having the large size, as the resin member, resin mixed with a glass filler is adopted, and it becomes possible to use resin having high melting temperature.
- FIG. 1 is an exploded perspective view showing main components of a solid polymer electrolyte fuel cell including a membrane electrode assembly according to a first embodiment of the present invention
- FIG. 2 is a cross sectional view showing the fuel cell, taken along a line II-II in FIG. 1 ;
- FIG. 3 is a front view showing a cathode of the membrane electrode assembly
- FIG. 4 is a partial cross sectional view showing an MEA having different sizes of components in a production method according to the first embodiment of the present invention
- FIG. 5 is a view showing a resin frame member
- FIG. 6 is a view showing a process of joining the MEA and the resin frame member
- FIG. 7 is a diagram showing steps of a production method according to a second embodiment of the present invention.
- FIG. 8 is a diagram showing steps of a production method according to a third embodiment of the present invention.
- FIG. 9 is a cross sectional view showing a solid polymer electrolyte fuel cell including a membrane electrode assembly according to a fourth embodiment of the present invention.
- FIG. 10 is a front view showing a cathode of the membrane electrode assembly
- FIG. 11 is a front view showing an anode of the membrane electrode assembly
- FIG. 12 is a view showing a method of producing the membrane electrode assembly
- FIG. 13 is a view showing a comparative example of the membrane electrode assembly
- FIG. 14 is a cross sectional view showing main components of a membrane electrode assembly according to a fifth embodiment of the present invention.
- FIG. 15 is a cross sectional view showing main components of a membrane electrode assembly according to a sixth embodiment of the present invention.
- FIG. 16 is a cross sectional view showing main components of a membrane electrode assembly according to a seventh embodiment of the present invention.
- FIG. 17 is a cross sectional view showing a solid polymer electrolyte fuel cell including a membrane electrode assembly according to an eighth embodiment of the present invention.
- FIG. 18 is a view showing a method of producing the membrane electrode assembly.
- FIG. 19 is a view showing a membrane electrode assembly disclosed in Japanese Laid-Open Patent Publication No. 2007-066766.
- a solid polymer electrolyte fuel cell 12 including a membrane electrode assembly 10 according to a first embodiment of the present invention is formed by sandwiching the membrane electrode assembly 10 between a first separator 14 and a second separator 16 .
- the first separator 14 and the second separator 16 are made of metal plates such as steel plates, stainless steel plates, aluminum plates, plated steel sheets, or metal plates having anti-corrosive surfaces by surface treatment.
- carbon members may be used as the first separator 14 and the second separator 16 .
- the membrane electrode assembly 10 includes a solid polymer electrolyte membrane 18 , and an anode (second electrode) 20 and a cathode (first electrode) 22 sandwiching the solid polymer electrolyte membrane 18 .
- the solid polymer electrolyte membrane 18 is formed by impregnating a thin membrane of perfluorosulfonic acid with water, for example.
- a fluorine based electrolyte may be used as the solid polymer electrolyte membrane 18 .
- an HC (hydrocarbon) based electrolyte may be used as the solid polymer electrolyte membrane 18 .
- the surface size (surface area) of the cathode 22 is smaller than the surface sizes (surface areas) of the solid polymer electrolyte membrane 18 and the anode 20 . It should be noted that the surface size of the cathode 22 may be equal to or larger than the surface size of the anode 20 .
- the anode 20 is provided on one surface 18 a of the solid polymer electrolyte membrane 18 and the cathode 22 is provided on the other surface 18 b of the solid polymer electrolyte membrane 18 such that a frame shaped outer portion of the solid polymer electrolyte membrane 18 is exposed.
- the anode 20 includes an electrode catalyst layer 20 a joined to the surface 18 a of the solid polymer electrolyte membrane 18 and a gas diffusion layer 20 c stacked on the electrode catalyst layer 20 a through an intermediate layer (underlying layer) 20 b .
- the cathode 22 includes an electrode catalyst layer 22 a joined to the surface 18 b of the solid polymer electrolyte membrane 18 and a gas diffusion layer 22 c stacked on the electrode catalyst layer 22 a through an intermediate layer (underlying layer) 22 b.
- Each of the electrode catalyst layers 20 a , 22 a is formed by carbon black supporting platinum particles as catalyst particles.
- polymer electrolyte As an ion conductive binder, polymer electrolyte is used. Catalyst paste formed by mixing the catalyst particles uniformly in the solution of this polymer electrolyte is printed, applied (coated) or transferred on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 to form the electrode catalyst layers 20 a , 22 a.
- Carbon black and FEP (fluorinated ethylene-propylene copolymer) particles and carbon nanotube are prepared in a form of paste, and coated on the gas diffusion layer 20 c , 22 c to form the intermediate layers 20 b , 22 b .
- the gas diffusion layers 20 c , 22 c are made of carbon papers or the like, and the surface size of the gas diffusion layer 20 c is larger that the surface size of the gas diffusion layer 22 c.
- the membrane electrode assembly 10 includes a resin frame member 24 formed around the solid polymer electrolyte membrane 18 , and joined only to the cathode 22 of the solid polymer electrolyte membrane 18 .
- the resin frame member 24 is made of PPS (poly phenylene sulfide), PPA (polyphthalamide), etc., and includes an impregnation portion 26 for impregnation of only the outer marginal portion of the cathode 22 with the inner marginal portion of the resin frame member 24 .
- an oxygen-containing gas supply passage 30 a for supplying an oxygen-containing gas, a coolant supply passage 32 a for supplying a coolant, and a fuel gas discharge passage 34 b for discharging a fuel gas such as a hydrogen-containing gas are arranged in a vertical direction indicated by an arrow C.
- the oxygen-containing gas supply passage 30 a , the coolant supply passage 32 a , and the fuel gas discharge passage 34 b extend through the fuel cell 12 in a stacking direction indicated by an arrow A.
- a fuel gas supply passage 34 a for supplying the fuel gas, a coolant discharge passage 32 b for discharging the coolant, and an oxygen-containing gas discharge passage 30 b for discharging the oxygen-containing gas are arranged in the direction indicated by the arrow C.
- the fuel gas supply passage 34 a , the coolant discharge passage 32 b , and the oxygen-containing gas discharge passage 30 b extend through the fuel cell 12 in the direction indicated by the arrow A.
- the second separator 16 has an oxygen-containing gas flow field 36 on its surface 16 a facing the membrane electrode assembly 10 .
- the oxygen-containing gas flow field 36 is connected to the oxygen-containing gas supply passage 30 a and the oxygen-containing gas discharge passage 30 b.
- the first separator 14 has a fuel gas flow field 38 on its surface 14 a facing the membrane electrode assembly 10 .
- the fuel gas flow field 38 is connected to the fuel gas supply passage 34 a and the fuel gas discharge passage 34 b .
- a coolant flow field 40 is formed between a surface 14 b of the first separator 14 and a surface 16 b of the second separator 16 .
- the coolant flow field 40 is connected to the coolant supply passage 32 a and the coolant discharge passage 32 b.
- a first seal member 42 is formed integrally with the surfaces 14 a , 14 b of the first separator 14 , around the outer end of the first separator 14 .
- a second seal member 44 is formed integrally with the surfaces 16 a , 16 b of the second separator 16 , around the outer end of the second separator 16 .
- the first seal member 42 includes a first ridge seal 42 a which contacts the resin frame member 24 of the membrane electrode assembly 10 , and a second ridge seal 42 b interposed between the first separator 14 and the second separator 16 .
- the second seal member 44 is a flat surface seal. Instead of providing the second ridge seal 42 b , the second seal member 44 may have a ridge seal (not shown).
- Each of the first seal member 42 and the second seal members 44 is made of seal material, cushion material, or packing material such as an EPDM (ethylene propylene diene monomer) rubber, an NBR (nitrile butadiene rubber), a fluoro rubber, a silicone rubber, a fluorosilicone rubber, a butyl rubber, a natural rubber, a styrene rubber, a chloroprene rubber, or an acrylic rubber.
- EPDM ethylene propylene diene monomer
- NBR nitrile butadiene rubber
- fluoro rubber a silicone rubber
- fluorosilicone rubber a butyl rubber
- natural rubber a styrene rubber
- chloroprene rubber a chloroprene rubber
- acrylic rubber acrylic rubber
- the first separator 14 has supply holes 46 connecting the fuel gas supply passage 34 a to the fuel gas flow field 38 , and discharge holes 48 connecting the fuel gas flow field 38 to the fuel gas discharge passage 34 b.
- an MEA 50 having different sizes of components is produced. Specifically, the electrode catalyst layers 20 a , 22 a are coated on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 , and the intermediate layers 20 b , 22 b each comprising a mixture of water-repellent agent and carbon particles are coated on the gas diffusion layers 20 c , 22 c.
- the gas diffusion layer 20 c is placed on a side adjacent to the surface 18 a of the solid polymer electrolyte membrane 18 , i.e., the gas diffusion layer 20 c is placed such that the intermediate layer 20 b faces the electrode catalyst layer 20 a .
- the gas diffusion layer 22 c is placed on a side adjacent to the surface 18 b of the solid polymer electrolyte membrane 18 , i.e., the gas diffusion layer 22 c is placed such that the intermediate layer 22 b faces the electrode catalyst layer 22 a .
- the resin frame member 24 is formed by an injection molding machine (not shown) beforehand.
- the dimension (width) H 1 of the resin frame member 24 and the dimension (thickness) H 1 of the MEA 50 are the same.
- the resin frame member 24 has an inner extension 24 a at its inner marginal portion.
- the thickness H 2 of the inner extension 24 a and the thickness H 2 of the cathode 22 of the MEA 50 are the same.
- the extension length L of the inner extension 24 a is the sum of the distance from the front end of the solid polymer electrolyte membrane 18 of the MEA 50 to the front end of the cathode 22 and the length of the impregnation portion 26 .
- the MEA 50 is placed on a base table 52 such that the anode 20 is positioned on the lower side.
- the front end of the inner extension 24 a of the resin frame member 24 is overlapped with the outer marginal portion of the cathode 22 of the MEA 50 .
- a glass plate 54 is placed on the resin frame member 24 .
- a load F is applied to the resin frame member 24 through the glass plate 54 , toward the base table 52 , and a laser beam Lb is radiated from a laser machine 56 through the glass plate 54 to the overlapped portions (an area where the outer marginal portion of the cathode 22 and the inner marginal portion of the resin frame member 24 are overlapped with each other).
- the inner extension 24 a of the resin frame member 24 as the inner marginal portion is locally heated in a concentrated manner, and melted.
- the gas diffusion layer 22 c of the cathode 22 is impregnated with the melted resin of the inner extension 24 a of the resin frame member 24 . Therefore, as shown in FIG. 2 , the resin frame member 24 is joined to the cathode 22 by the impregnation portion 26 where only the outer marginal portion of the cathode 22 is impregnated with the melted resin of the inner marginal portion of the resin frame member 24 . In this manner, the membrane electrode assembly 10 is produced.
- the joining strength for joining the resin frame member 24 to the cathode 22 is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- the resin frame member 24 is joined only to the cathode 22 , the portion of the resin frame member 24 where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of the resin frame member 24 .
- the heating treatment is applied only to the overlapped portions in a concentrated manner by laser heating using the laser machine 56 . Therefore, since the resin frame member 24 is heated only locally, the time required for melting is reduced. Accordingly, cost reduction is achieved, and deformation is reduced as much as possible. It should be noted that infrared welding, impulse welding or the like may be adopted instead of laser welding using the laser machine 56 .
- an oxygen-containing gas is supplied to the oxygen-containing gas supply passage 30 a , and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas supply passage 34 a . Further, coolant such as pure water, ethylene glycol, or oil is supplied to the coolant supply passage 32 a.
- the oxygen-containing gas flows from the oxygen-containing gas supply passage 30 a to the oxygen-containing gas flow field 36 of the second separator 16 .
- the oxygen-containing gas moves in the direction indicated by the arrow B, and the oxygen-containing gas is supplied to the cathode 22 of the membrane electrode assembly 10 .
- the fuel gas flows from the fuel gas supply passage 34 a through the supply holes 46 into the fuel gas flow field 38 of the first separator 14 .
- the fuel gas flows along the fuel gas flow field 38 in the direction indicated by the arrow B, and the fuel gas is supplied to the anode 20 of the membrane electrode assembly 10 .
- the oxygen-containing gas supplied to the cathode 22 and the fuel gas supplied to the anode 20 are partially consumed in the electrochemical reactions in the electrode catalyst layers for generating electricity.
- the oxygen-containing gas partially consumed at the cathode 22 flows along the oxygen-containing gas discharge passage 30 b , and the oxygen-containing gas is discharged in the direction indicated by the arrow A.
- the fuel gas partially consumed at the anode 20 flows through the discharge holes 48 .
- the fuel gas flow along the fuel gas discharge passage 34 b , and the fuel gas is discharged in the direction indicated by the arrow A.
- the coolant supplied to the coolant supply passage 32 a flows into the coolant flow field 40 between the first separator 14 and the second separator 16 . Then, the coolant flows in the direction indicated by the arrow B. After the coolant cools the membrane electrode assembly 10 , the coolant is discharged into the coolant discharge passage 32 b.
- FIG. 7 is a diagram showing steps of a method of producing the membrane electrode assembly 10 according to a second embodiment of the present invention.
- the intermediate layer 20 b is coated on the gas diffusion layer of the anode (S 1 ), and the intermediate layer 22 b is coated on the gas diffusion layer 22 c of the cathode (S 2 ).
- the resin frame member 24 formed by injection molding beforehand is joined to the gas diffusion layer 22 c (S 3 ).
- the process of joining the gas diffusion layer 22 c of the cathode 22 to the resin frame member 24 is substantially the same as in the case of the first embodiment.
- the gas diffusion layer 22 c and the resin frame member 24 are joined together by placing the gas diffusion layer 22 c on the base table 52 shown in FIG. 6 . In this manner, the resin frame member 24 and the gas diffusion layer 22 c of the cathode 22 are combined into one piece by the impregnation portion 26 .
- the electrode catalyst layers 20 a , 22 a are coated on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 (S 4 ). Further, the gas diffusion layer 20 c of the anode and the gas diffusion layer 22 c joined to the resin frame member 24 are placed on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 , respectively. These components are subjected to hot pressing treatment to produce the membrane electrode assembly 10 (S 5 ).
- FIG. 8 is a diagram showing steps of a method of producing a membrane electrode assembly 10 according to a third embodiment of the present invention.
- the electrode catalyst layer 20 a is coated on the intermediate layer 20 b of the gas diffusion layer 20 c (S 12 ).
- the resin frame member 24 is joined to the gas diffusion layer 22 c (S 14 ). The process of joining the gas diffusion layer 22 c to the resin frame member 24 is the same as in the cases of the first and second embodiments.
- the electrode catalyst layer 22 a of the cathode is coated on the surface 18 b of the solid polymer electrolyte membrane 18 (S 15 ). Then, the gas diffusion layer 20 c of the anode and the gas diffusion layer 22 c of the cathode joined to the resin frame member 24 are placed on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 , respectively. These components are subjected to hot pressing treatment to produce the membrane electrode assembly 10 (S 16 ).
- FIG. 9 is a cross sectional view showing a solid polymer electrolyte fuel cell 62 including a membrane electrode assembly 60 according to a fourth embodiment of the present invention.
- the constituent elements of the solid polymer electrolyte fuel cell 62 that are identical to those of the solid polymer electrolyte fuel cell 12 including the membrane electrode assembly 10 according to the first embodiment are labeled with the same reference numerals, and descriptions thereof will be omitted.
- the constituent elements that are identical to those of the solid polymer electrolyte fuel cell 12 including the membrane electrode assembly 10 according to the first embodiment are labeled with the same reference numerals, and descriptions thereof will be omitted.
- the anode 20 includes an electrode catalyst layer 20 a joined to the surface 18 a of the solid polymer electrolyte membrane 18 and a gas diffusion layer 20 c stacked on the electrode catalyst layer 20 a .
- the cathode 22 includes an electrode catalyst layer 22 a joined to the surface 18 b of the solid polymer electrolyte membrane 18 and a gas diffusion layer 22 c stacked on the electrode catalyst layer 22 a .
- the electrode catalyst layer 20 a and the gas diffusion layer 20 c may be provided through an intermediate layer (underlying layer).
- the electrode catalyst layer 22 a and the gas diffusion layer 22 c may be provided through an intermediate layer (underlying layer).
- the resin frame member 24 and the gas diffusion layer 22 c of the cathode 22 are combined into one piece by a first resin impregnation portion 26 a
- the resin frame member 24 and the gas diffusion layer 20 c of the anode 20 are combined into one piece by a second resin impregnation portion 26 b.
- the first resin impregnation portion 26 a is formed over the entire circumference of the gas diffusion layer 22 c of the cathode 22 .
- the width L 1 on the long side of the first resin impregnation portion 26 a (side extending in the direction indicated by the arrow B) is larger than the width L 2 on the short side of the first resin impregnation portion 26 a (side extending in the direction indicated by the arrow C) (L 1 >L 2 ).
- the second resin impregnation portion 26 b is formed over the entire circumference of the gas diffusion layer 20 c of the anode 20 .
- the width L 3 on the long side of the second resin impregnation portion 26 b (side extending in the direction indicated by the arrow B) is larger than the width L 4 on the short side of the second resin impregnation portion 26 b (side extending in the direction indicated by the arrow C) (L 3 >L 4 ).
- the second resin impregnation portion 26 b is terminated at a position spaced outward of a first inner circumferential portion 24 c of the resin frame member 24 adjacent to the cathode 22 by the distance H. That is, the second resin impregnation portion 26 b is not provided at a position overlapped with the cathode 22 in the stacking direction.
- an MEA 64 having different sizes of components (stepped-type MEA) of the membrane electrode assembly 60 is produced.
- the electrode catalyst layers 20 a , 22 a are coated on both surfaces 18 a , 18 b of the solid polymer electrolyte membrane 18 .
- the gas diffusion layer 20 c is placed adjacent to the surface 18 a of the solid polymer electrolyte membrane 18 , i.e., on the electrode catalyst layer 20 a
- the gas diffusion layer 22 c is placed adjacent to the surface 18 b of the solid polymer electrolyte membrane 18 , i.e., on the electrode catalyst layer 22 a .
- These components are stacked together, and subjected to hot pressing treatment to produce the MEA 64 .
- the resin frame member 24 is formed beforehand by an injection molding machine (not shown).
- the resin frame member 24 is positioned in alignment with the MEA 64 .
- the resin frame member 24 has the first inner circumferential portion 24 c and a second inner circumferential portion 24 d .
- the end of the cathode 22 is positioned at the first inner circumferential portion 24 c
- the end of the anode 20 is positioned at the second inner circumferential portion 24 d.
- a first resin member 26 aa forming the first resin impregnation portion 26 a is prepared at the cathode 22
- a second resin member 26 bb forming the second resin impregnation portion 26 b is prepared at the anode 20 .
- Each of the first resin member 26 aa and the second resin member 26 bb has a frame shape, and is made of the same material as the resin frame member 24 , for example.
- the resin frame member 24 uses resin material enforced by mixing a filler with the resin material.
- the first resin member 26 aa and the second resin member 26 bb may be made of resin material which is not mixed with any filler.
- the MEA 64 and the resin frame member 24 can be joined together.
- the first resin member 26 aa and the second resin member 26 bb are placed over the MEA 64 and the resin frame member 24 and a load is applied to the MEA 64 and the resin frame member 24 through the first resin member 26 aa and the second resin member 26 bb , the first resin member 26 aa and the second resin member 26 bb are heated.
- a heating method any of laser welding, infrared welding, and impulse welding, etc. is adopted.
- the first resin member 26 aa and the second resin member 26 bb are melted by heating.
- Both of the gas diffusion layer 22 c of the cathode 22 and the resin frame member 24 are impregnated with the melted resin of the first resin member 26 aa
- both of the gas diffusion layer 20 c of the anode 20 and the resin frame member 24 are impregnated with the melted resin of the second resin member 26 bb.
- the first resin impregnation portion 26 a is formed over the gas diffusion layer 22 c of the cathode 22 and the resin frame member 24
- the second resin impregnation portion 26 b is formed over the gas diffusion layer 20 c of the anode 20 and the resin frame member 24 to produce the membrane electrode assembly 60 .
- the outer ends of the gas diffusion layers 22 c , 20 c of the cathode 22 and the anode 20 and the resin frame member 24 are impregnated with resin, respectively, and formed integrally with the first resin impregnation portion 26 a and the second resin impregnation portion 26 b.
- the joining strength for joining the resin frame member 24 to the cathode 22 and the anode 20 is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- the width L 1 on the long side of the first resin impregnation portion 26 a is larger than the width L 2 on the short side of the first resin impregnation portion 26 a (L 1 >L 2 ) (see FIG. 10 ).
- the width L 3 on the long side of the second resin impregnation portion 26 b is larger than the width L 4 on the short side of the second resin impregnation portion 26 b (L 3 >L 4 ) (see FIG. 11 ).
- the second resin impregnation portion 26 b is terminated at a position spaced outward of the first inner circumferential portion 24 c of the resin frame member 24 adjacent to the cathode 22 , by the distance H.
- the distance H In the range of the distance H, since the electrode catalyst layer 22 a of the cathode 22 facing the anode 20 is not present, abnormal reaction does not occur.
- the gas diffusion layer 22 c of the cathode 22 and the resin frame member 24 are combined into one piece by a first resin impregnation portion 27 a .
- the gas diffusion layer 20 c of the anode 20 and the resin frame member 24 are combined into one piece by a second resin impregnation portion 27 b .
- the second resin impregnation portion 27 b extends inward of the end of the first resin impregnation portion 27 a by the distance Ha.
- the electrode catalyst layer 22 a of the cathode 22 is present in the range of the distance Ha where the second resin impregnation portion 27 b is provided.
- shortage of hydrogen occurs at the anode 20 in the range of the distance Ha, and abnormal reaction tends to occur at the cathode 22 .
- FIG. 14 is a cross sectional view showing main components of a membrane electrode assembly 70 according to a fifth embodiment of the present invention.
- the membrane electrode assembly 70 includes a resin frame member 72 joined to the cathode 22 and the anode 20 .
- a first resin protrusion 74 a and a second resin protrusion 74 b are formed integrally with the resin frame member 72 for combining the resin frame member 72 and the gas diffusion layer 22 c of the cathode 22 into one piece, and combining the resin frame member 72 and the gas diffusion layer 20 c of the anode 20 into one piece.
- the first resin protrusion 74 a is formed in a frame shape around the first inner circumferential portion 24 c
- the second resin protrusion 74 b is formed in a frame shape around the second inner circumferential portion 24 d .
- the first resin protrusion 74 a has an inclined surface 74 as as an end surface opposite to the first inner circumferential portion 24 c , and the inclined surface 74 as is inclined in a direction spaced from the resin frame member 72 .
- the second resin protrusion 74 b has an inclined surface 74 bs as an end surface opposite to the second inner circumferential portion 24 d , and the inclined surface 74 bs is inclined in a direction spaced from the resin frame member 72 .
- the first resin protrusion 74 a and the second resin protrusion 74 b are heated by a heating machine (not shown), and melted.
- a heating machine not shown
- the gas diffusion layers 22 c , 20 c are impregnated with the melted resin of the first resin protrusion 74 a and the second resin protrusion 74 b .
- the first resin impregnation portion 26 a and the second resin impregnation portion 26 b are formed.
- FIG. 15 is a cross sectional view showing main components of a membrane electrode assembly 80 according to a sixth embodiment of the present invention.
- the membrane electrode assembly 80 includes a resin frame member 82 joined to the cathode 22 and the anode 20 .
- the resin frame member 82 includes a first resin member 84 a and a second resin member 84 b for combining the resin frame member 82 and the gas diffusion layer 22 c of the cathode 22 into one piece, and combining the resin frame member 82 and the gas diffusion layer 20 c of the anode 20 into one piece.
- the first resin member 84 a and the second resin member 84 b are formed integrally with the resin frame member 82 by insert molding beforehand.
- the first resin member 84 a and the second resin member 84 b are heated by a heating machine (not shown), and melted.
- a heating machine not shown
- the gas diffusion layers 22 c , 20 c are impregnated with the melted resin of the first resin member 84 a and the second resin member 84 b .
- the first resin impregnation portion 26 a and the second resin impregnation portion 26 b are formed.
- FIG. 16 is a cross sectional view showing a membrane electrode assembly 90 according to a seventh embodiment of the present invention.
- the membrane electrode assembly 90 includes a resin frame member 92 joined to the cathode 22 and the anode 20 .
- a first resin protrusion 94 a and a second resin protrusion 94 b are provided integrally with the resin frame member 92 for combining the resin frame member 92 and the gas diffusion layer 22 c of the cathode 22 into one piece, and combining the resin frame member 92 and the gas diffusion layer 20 c of the anode 20 into one piece.
- the first resin protrusion 94 a is formed in a frame shape around the first inner circumferential portion 24 c
- the second resin protrusion 94 b is formed in a frame shape around the second inner circumferential portion 24 d.
- Each of the first resin protrusion 94 a and the second resin protrusion 94 b has a rectangular shape in cross section.
- the first resin protrusion 94 a and the second resin protrusion 94 b are formed by eliminating the inclined surfaces 74 as , 74 bs of the first resin protrusion 74 a and the second resin protrusion 74 b in the membrane electrode assembly 70 according to the fifth embodiment.
- the first resin protrusion 94 a and the second resin protrusion 94 b are heated by a heating machine (not shown), and melted.
- the gas diffusion layers 22 c , 20 c are impregnated with the melted resin of the first resin protrusion 94 a and the second resin protrusion 94 b .
- the first resin impregnation portion 26 a and the second resin impregnation portion 26 b are formed.
- FIG. 17 is a cross sectional view showing a solid polymer electrolyte fuel cell 102 including a membrane electrode assembly 100 according to an eighth embodiment of the present invention.
- the resin frame member 24 and the gas diffusion layer 20 c of the anode 20 are combined into one piece by a resin impregnation portion 104 . That is, the resin frame member 24 is joined only to the anode 20 which is larger than the cathode 22 .
- an MEA 106 having different sizes of components (stepped-type MEA) of the membrane electrode assembly 100 is produced.
- a resin member 104 a for forming the resin impregnation portion 104 is prepared.
- the resin member 104 a has a frame shape, and uses resin material enforced by mixing a glass filler with the resin material.
- the resin member 104 a is heated.
- the heated resin member 104 a is melted to form the resin impregnation portion 104 over the gas diffusion layer 20 c of the anode 20 and the resin frame member 24 .
- the membrane electrode assembly 100 is produced.
- the glass filler when the resin member 104 a is heated, and melted, the glass filler does not enter the gas diffusion layer 20 c . Therefore, the resin member 104 a does not directly contact the solid polymer electrolyte membrane 18 .
- the resin member 104 a it become possible to adopt resin mixed with a glass filler, and use resin having high melting temperature.
- the resin used for the resin member 104 a can be adopted from a wide variety of selection advantageously.
Abstract
An electrolyte membrane-electrode assembly is provided with: a solid polymer electrolyte membrane; and an anode-side electrode and a cathode-side electrode that sandwich the solid polymer electrolyte membrane. The cathode-side electrode has smaller planar dimensions than the anode-side electrode. In the electrolyte membrane-electrode assembly, a resin frame member is provided around the outer periphery of the solid polymer electrolyte membrane. The resin frame member is bonded to the cathode-side electrode by having only the outer peripheral portion of the cathode-side electrode being impregnated with the inner peripheral portion of the resin frame member.
Description
- The present invention relates to a fuel cell membrane electrode assembly (electrolyte membrane-electrode assembly for fuel cells), and a method of producing the fuel cell membrane electrode assembly. The fuel cell membrane electrode assembly includes a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane. Each of the first electrode and the second electrode includes an electrode catalyst layer and a gas diffusion layer. The outer size of the first electrode is smaller than the outer size of the second electrode.
- In general, a solid polymer electrolyte fuel cell employs a solid polymer electrolyte membrane. The solid polymer electrolyte membrane is a polymer ion exchange membrane. The fuel cell includes a membrane electrode assembly (MEA) where an anode and a cathode are provided on both sides of the solid polymer electrolyte membrane. Each of the anode and the cathode includes a catalyst layer (electrode catalyst layer) and a gas diffusion layer (porous carbon). In the fuel cell, the membrane electrode assembly is sandwiched between separators (bipolar plates). A predetermined number of the fuel cells are stacked together to form a fuel cell stack. For example, the fuel cell stack is mounted in a fuel cell electric vehicle as an in-vehicle fuel cell stack.
- In certain cases, the membrane electrode assembly has structure where components of the MEA have different sizes, i.e., the surface size (surface area) of one of diffusion layers is smaller than the surface size (surface area) of the solid polymer electrolyte membrane, and the surface size of the other of the gas diffusion layers is the same as the surface size of the solid polymer electrolyte membrane (a stepped-type MEA).
- Normally, in the fuel cell stack, a large number of membrane electrode assemblies are stacked together. In order to reduce the cost, there is a demand to produce the membrane electrode assembly at low cost. Therefore, in particular, for the purpose of reducing the amount of expensive material used for the solid polymer electrolyte membrane, and simplify the structure of the solid polymer electrolyte membrane, various proposals have been made.
- For example, as shown in
FIG. 19 , a membrane electrode assembly disclosed in Japanese Laid-Open Patent Publication No. 2007-066766 (hereinafter referred to as conventional technique) includes anelectrolyte membrane 1, acathode catalyst layer 2 a provided on one side of theelectrolyte membrane 1, ananode catalyst layer 2 b provided on the other surface of theelectrolyte membrane 1, andgas diffusion layers electrolyte membrane 1. - The surface area of the
gas diffusion layer 3 b of the anode is equal to the surface area of theelectrolyte membrane 1, and larger than the surface area of thegas diffusion layer 3 a of the cathode. Agasket structure body 4 is provided in an edge area of the membrane electrode assembly (MEA), and the outer end of theelectrolyte membrane 1 adjacent to thegas diffusion layer 3 a is joined to thegasket structure body 4 through anadhesive layer 5. - However, in the conventional technique, the MEA and the
gasket structure body 4 are fixed to the outer marginal portion of theelectrolyte membrane 1 exposed to the outside from thegas diffusion layer 3 a, through theadhesive layer 5 only. Therefore, the strength of joining the MEA and thegasket structure body 4 is low, and the desired strength cannot be obtained. - The present invention has been made to solve the problem of this type, and an object of the present invention is to provide a fuel cell membrane electrode assembly and a method of producing the fuel cell membrane electrode assembly in which it is possible to firmly and easily join a resin frame member around a solid polymer electrolyte membrane, and suitably suppress deformation of the resin frame member.
- The present invention relates to a fuel cell membrane electrode assembly, and a method of producing the fuel cell membrane electrode assembly. The fuel cell membrane electrode assembly includes a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane. Each of the first electrode and the second electrode includes an electrode catalyst layer and a gas diffusion layer. An outer size of the first electrode is smaller than an outer size of the second electrode.
- The membrane electrode assembly includes a resin frame member provided around the solid polymer electrolyte membrane and an impregnation portion for joining the resin frame member and at least one of an outer marginal portion of the first electrode and an outer marginal portion of the second electrode together.
- Further, the production method includes the steps of forming the first electrode and the second electrode on both sides of the solid polymer electrolyte membrane, forming a resin frame member, and overlapping an outer marginal portion of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member around the solid polymer electrolyte membrane.
- Further, the production method includes the steps of overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode, forming the electrode catalyst layers on both surfaces of the solid polymer electrolyte membrane, and combining the gas diffusion layer of the first electrode joined to the resin frame member and the gas diffusion layer of the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
- Further, the production method includes the steps of overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate only the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode, forming the electrode catalyst layer on the gas diffusion layer of the second electrode and forming the electrode catalyst layer of the first electrode on one side of the solid polymer electrolyte membrane, and combining the first electrode joined to the resin frame member and the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
- In the present invention, the impregnation portion joining the resin frame member and the at least one of the outer marginal portion of the first electrode and the outer marginal portion of the second electrode together is provided. In the structure, in comparison with the case where the resin frame member is joined to the first electrode or the second electrode by adhesion, the joining strength for joining the resin frame member to at least one of the first electrode and the second electrode is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- In the production method of the present invention, the resin frame member is joined only to the first electrode. Therefore, the portion of the resin frame member where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of the resin frame member. Thus, it is possible to firmly and easily join the resin frame member around the solid polymer electrolyte membrane, and suitably suppress deformation of the resin frame member.
- Further, in the present invention, the outer ends of the gas diffusion layers of the first electrode and the second electrode and the resin frame member are impregnated with resin to form the resin impregnation portion integrally. In the structure, in comparison with the case where the resin frame member is joined to the first electrode and the second electrode by adhesion, the joining strength for joining the resin frame member to the first electrode and the second electrode is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible.
- Further, in the present invention, the outer end of the gas diffusion of the second electrode and the resin frame member are impregnated with resin to form the resin impregnation portion integrally. Therefore, the portion of the resin frame member where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of the resin frame member. Further, since the resin impregnation portion is provided only at the second electrode having the large size, as the resin member, resin mixed with a glass filler is adopted, and it becomes possible to use resin having high melting temperature.
-
FIG. 1 is an exploded perspective view showing main components of a solid polymer electrolyte fuel cell including a membrane electrode assembly according to a first embodiment of the present invention; -
FIG. 2 is a cross sectional view showing the fuel cell, taken along a line II-II inFIG. 1 ; -
FIG. 3 is a front view showing a cathode of the membrane electrode assembly; -
FIG. 4 is a partial cross sectional view showing an MEA having different sizes of components in a production method according to the first embodiment of the present invention; -
FIG. 5 is a view showing a resin frame member; -
FIG. 6 is a view showing a process of joining the MEA and the resin frame member; -
FIG. 7 is a diagram showing steps of a production method according to a second embodiment of the present invention; -
FIG. 8 is a diagram showing steps of a production method according to a third embodiment of the present invention; -
FIG. 9 is a cross sectional view showing a solid polymer electrolyte fuel cell including a membrane electrode assembly according to a fourth embodiment of the present invention; -
FIG. 10 is a front view showing a cathode of the membrane electrode assembly; -
FIG. 11 is a front view showing an anode of the membrane electrode assembly; -
FIG. 12 is a view showing a method of producing the membrane electrode assembly; -
FIG. 13 is a view showing a comparative example of the membrane electrode assembly; -
FIG. 14 is a cross sectional view showing main components of a membrane electrode assembly according to a fifth embodiment of the present invention; -
FIG. 15 is a cross sectional view showing main components of a membrane electrode assembly according to a sixth embodiment of the present invention; -
FIG. 16 is a cross sectional view showing main components of a membrane electrode assembly according to a seventh embodiment of the present invention; -
FIG. 17 is a cross sectional view showing a solid polymer electrolyte fuel cell including a membrane electrode assembly according to an eighth embodiment of the present invention; -
FIG. 18 is a view showing a method of producing the membrane electrode assembly; and -
FIG. 19 is a view showing a membrane electrode assembly disclosed in Japanese Laid-Open Patent Publication No. 2007-066766. - As shown in
FIGS. 1 and 2 , a solid polymerelectrolyte fuel cell 12 including amembrane electrode assembly 10 according to a first embodiment of the present invention is formed by sandwiching themembrane electrode assembly 10 between afirst separator 14 and asecond separator 16. For example, thefirst separator 14 and thesecond separator 16 are made of metal plates such as steel plates, stainless steel plates, aluminum plates, plated steel sheets, or metal plates having anti-corrosive surfaces by surface treatment. Alternatively, carbon members may be used as thefirst separator 14 and thesecond separator 16. - As shown in
FIG. 2 , themembrane electrode assembly 10 includes a solidpolymer electrolyte membrane 18, and an anode (second electrode) 20 and a cathode (first electrode) 22 sandwiching the solidpolymer electrolyte membrane 18. The solidpolymer electrolyte membrane 18 is formed by impregnating a thin membrane of perfluorosulfonic acid with water, for example. A fluorine based electrolyte may be used as the solidpolymer electrolyte membrane 18. Alternatively, an HC (hydrocarbon) based electrolyte may be used as the solidpolymer electrolyte membrane 18. - The surface size (surface area) of the
cathode 22 is smaller than the surface sizes (surface areas) of the solidpolymer electrolyte membrane 18 and theanode 20. It should be noted that the surface size of thecathode 22 may be equal to or larger than the surface size of theanode 20. - The
anode 20 is provided on onesurface 18 a of the solidpolymer electrolyte membrane 18 and thecathode 22 is provided on theother surface 18 b of the solidpolymer electrolyte membrane 18 such that a frame shaped outer portion of the solidpolymer electrolyte membrane 18 is exposed. - The
anode 20 includes anelectrode catalyst layer 20 a joined to thesurface 18 a of the solidpolymer electrolyte membrane 18 and agas diffusion layer 20 c stacked on theelectrode catalyst layer 20 a through an intermediate layer (underlying layer) 20 b. Thecathode 22 includes anelectrode catalyst layer 22 a joined to thesurface 18 b of the solidpolymer electrolyte membrane 18 and agas diffusion layer 22 c stacked on theelectrode catalyst layer 22 a through an intermediate layer (underlying layer) 22 b. - Each of the electrode catalyst layers 20 a, 22 a is formed by carbon black supporting platinum particles as catalyst particles. As an ion conductive binder, polymer electrolyte is used. Catalyst paste formed by mixing the catalyst particles uniformly in the solution of this polymer electrolyte is printed, applied (coated) or transferred on both
surfaces polymer electrolyte membrane 18 to form the electrode catalyst layers 20 a, 22 a. - Carbon black and FEP (fluorinated ethylene-propylene copolymer) particles and carbon nanotube are prepared in a form of paste, and coated on the
gas diffusion layer intermediate layers gas diffusion layer 20 c is larger that the surface size of thegas diffusion layer 22 c. - As shown in
FIGS. 2 and 3 , themembrane electrode assembly 10 includes aresin frame member 24 formed around the solidpolymer electrolyte membrane 18, and joined only to thecathode 22 of the solidpolymer electrolyte membrane 18. For example, theresin frame member 24 is made of PPS (poly phenylene sulfide), PPA (polyphthalamide), etc., and includes animpregnation portion 26 for impregnation of only the outer marginal portion of thecathode 22 with the inner marginal portion of theresin frame member 24. - As shown in
FIG. 1 , at one end of thefuel cell 12 in a direction indicated by an arrow B (horizontal direction inFIG. 1 ), an oxygen-containinggas supply passage 30 a for supplying an oxygen-containing gas, acoolant supply passage 32 a for supplying a coolant, and a fuelgas discharge passage 34 b for discharging a fuel gas such as a hydrogen-containing gas are arranged in a vertical direction indicated by an arrow C. The oxygen-containinggas supply passage 30 a, thecoolant supply passage 32 a, and the fuelgas discharge passage 34 b extend through thefuel cell 12 in a stacking direction indicated by an arrow A. - At the other end of the
fuel cell 12 in the direction indicated by the arrow B, a fuelgas supply passage 34 a for supplying the fuel gas, acoolant discharge passage 32 b for discharging the coolant, and an oxygen-containinggas discharge passage 30 b for discharging the oxygen-containing gas are arranged in the direction indicated by the arrow C. The fuelgas supply passage 34 a, thecoolant discharge passage 32 b, and the oxygen-containinggas discharge passage 30 b extend through thefuel cell 12 in the direction indicated by the arrow A. - The
second separator 16 has an oxygen-containinggas flow field 36 on itssurface 16 a facing themembrane electrode assembly 10. The oxygen-containinggas flow field 36 is connected to the oxygen-containinggas supply passage 30 a and the oxygen-containinggas discharge passage 30 b. - The
first separator 14 has a fuelgas flow field 38 on itssurface 14 a facing themembrane electrode assembly 10. The fuelgas flow field 38 is connected to the fuelgas supply passage 34 a and the fuelgas discharge passage 34 b. Acoolant flow field 40 is formed between asurface 14 b of thefirst separator 14 and asurface 16 b of thesecond separator 16. Thecoolant flow field 40 is connected to thecoolant supply passage 32 a and thecoolant discharge passage 32 b. - As shown in
FIGS. 1 and 2 , afirst seal member 42 is formed integrally with thesurfaces first separator 14, around the outer end of thefirst separator 14. Asecond seal member 44 is formed integrally with thesurfaces second separator 16, around the outer end of thesecond separator 16. - As shown in
FIG. 2 , thefirst seal member 42 includes afirst ridge seal 42 a which contacts theresin frame member 24 of themembrane electrode assembly 10, and asecond ridge seal 42 b interposed between thefirst separator 14 and thesecond separator 16. Thesecond seal member 44 is a flat surface seal. Instead of providing thesecond ridge seal 42 b, thesecond seal member 44 may have a ridge seal (not shown). - Each of the
first seal member 42 and thesecond seal members 44 is made of seal material, cushion material, or packing material such as an EPDM (ethylene propylene diene monomer) rubber, an NBR (nitrile butadiene rubber), a fluoro rubber, a silicone rubber, a fluorosilicone rubber, a butyl rubber, a natural rubber, a styrene rubber, a chloroprene rubber, or an acrylic rubber. - As shown in
FIG. 1 , thefirst separator 14 hassupply holes 46 connecting the fuelgas supply passage 34 a to the fuelgas flow field 38, and discharge holes 48 connecting the fuelgas flow field 38 to the fuelgas discharge passage 34 b. - In this
fuel cell 12, a method of producing themembrane electrode assembly 10 according to a first embodiment of the present invention will be described below. - Firstly, as shown in
FIG. 4 , anMEA 50 having different sizes of components is produced. Specifically, the electrode catalyst layers 20 a, 22 a are coated on bothsurfaces polymer electrolyte membrane 18, and theintermediate layers - Then, the
gas diffusion layer 20 c is placed on a side adjacent to thesurface 18 a of the solidpolymer electrolyte membrane 18, i.e., thegas diffusion layer 20 c is placed such that theintermediate layer 20 b faces theelectrode catalyst layer 20 a. Further, thegas diffusion layer 22 c is placed on a side adjacent to thesurface 18 b of the solidpolymer electrolyte membrane 18, i.e., thegas diffusion layer 22 c is placed such that theintermediate layer 22 b faces theelectrode catalyst layer 22 a. These components are stacked together, and subjected to hot pressing treatment to produce theMEA 50. - As shown in
FIG. 5 , theresin frame member 24 is formed by an injection molding machine (not shown) beforehand. The dimension (width) H1 of theresin frame member 24 and the dimension (thickness) H1 of theMEA 50 are the same. Theresin frame member 24 has aninner extension 24 a at its inner marginal portion. The thickness H2 of theinner extension 24 a and the thickness H2 of thecathode 22 of theMEA 50 are the same. The extension length L of theinner extension 24 a is the sum of the distance from the front end of the solidpolymer electrolyte membrane 18 of theMEA 50 to the front end of thecathode 22 and the length of theimpregnation portion 26. - Next, as shown in
FIG. 6 , theMEA 50 is placed on a base table 52 such that theanode 20 is positioned on the lower side. The front end of theinner extension 24 a of theresin frame member 24 is overlapped with the outer marginal portion of thecathode 22 of theMEA 50. Aglass plate 54 is placed on theresin frame member 24. A load F is applied to theresin frame member 24 through theglass plate 54, toward the base table 52, and a laser beam Lb is radiated from alaser machine 56 through theglass plate 54 to the overlapped portions (an area where the outer marginal portion of thecathode 22 and the inner marginal portion of theresin frame member 24 are overlapped with each other). - Thus, the
inner extension 24 a of theresin frame member 24 as the inner marginal portion is locally heated in a concentrated manner, and melted. Thegas diffusion layer 22 c of thecathode 22 is impregnated with the melted resin of theinner extension 24 a of theresin frame member 24. Therefore, as shown inFIG. 2 , theresin frame member 24 is joined to thecathode 22 by theimpregnation portion 26 where only the outer marginal portion of thecathode 22 is impregnated with the melted resin of the inner marginal portion of theresin frame member 24. In this manner, themembrane electrode assembly 10 is produced. - In the first embodiment, after the
MEA 50 and theresin frame member 24 are produced separately, only the outer marginal portion of thecathode 22 is impregnated with the melted resin of the inner marginal portion of theresin frame member 24 to join theresin frame member 24 to thecathode 22. Thus, in comparison with the case where theresin frame member 24 is joined to thecathode 22 by adhesion, the joining strength for joining theresin frame member 24 to thecathode 22 is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible. - Further, since the
resin frame member 24 is joined only to thecathode 22, the portion of theresin frame member 24 where heat contraction occurs is reduced, and it becomes possible to suppress occurrence of warpage or the like of theresin frame member 24. - In particular, the heating treatment is applied only to the overlapped portions in a concentrated manner by laser heating using the
laser machine 56. Therefore, since theresin frame member 24 is heated only locally, the time required for melting is reduced. Accordingly, cost reduction is achieved, and deformation is reduced as much as possible. It should be noted that infrared welding, impulse welding or the like may be adopted instead of laser welding using thelaser machine 56. - Operation of the
fuel cell 12 will be described. - Firstly, as shown in
FIG. 1 , an oxygen-containing gas is supplied to the oxygen-containinggas supply passage 30 a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuelgas supply passage 34 a. Further, coolant such as pure water, ethylene glycol, or oil is supplied to thecoolant supply passage 32 a. - Thus, the oxygen-containing gas flows from the oxygen-containing
gas supply passage 30 a to the oxygen-containinggas flow field 36 of thesecond separator 16. The oxygen-containing gas moves in the direction indicated by the arrow B, and the oxygen-containing gas is supplied to thecathode 22 of themembrane electrode assembly 10. In the meanwhile, the fuel gas flows from the fuelgas supply passage 34 a through the supply holes 46 into the fuelgas flow field 38 of thefirst separator 14. The fuel gas flows along the fuelgas flow field 38 in the direction indicated by the arrow B, and the fuel gas is supplied to theanode 20 of themembrane electrode assembly 10. - Thus, in each of the
membrane electrode assemblies 10, the oxygen-containing gas supplied to thecathode 22 and the fuel gas supplied to theanode 20 are partially consumed in the electrochemical reactions in the electrode catalyst layers for generating electricity. - Then, the oxygen-containing gas partially consumed at the
cathode 22 flows along the oxygen-containinggas discharge passage 30 b, and the oxygen-containing gas is discharged in the direction indicated by the arrow A. Likewise, the fuel gas partially consumed at theanode 20 flows through the discharge holes 48. Then, the fuel gas flow along the fuelgas discharge passage 34 b, and the fuel gas is discharged in the direction indicated by the arrow A. - Further, the coolant supplied to the
coolant supply passage 32 a flows into thecoolant flow field 40 between thefirst separator 14 and thesecond separator 16. Then, the coolant flows in the direction indicated by the arrow B. After the coolant cools themembrane electrode assembly 10, the coolant is discharged into thecoolant discharge passage 32 b. -
FIG. 7 is a diagram showing steps of a method of producing themembrane electrode assembly 10 according to a second embodiment of the present invention. - In the second embodiment, the
intermediate layer 20 b is coated on the gas diffusion layer of the anode (S1), and theintermediate layer 22 b is coated on thegas diffusion layer 22 c of the cathode (S2). Theresin frame member 24 formed by injection molding beforehand is joined to thegas diffusion layer 22 c (S3). The process of joining thegas diffusion layer 22 c of thecathode 22 to theresin frame member 24 is substantially the same as in the case of the first embodiment. For example, thegas diffusion layer 22 c and theresin frame member 24 are joined together by placing thegas diffusion layer 22 c on the base table 52 shown inFIG. 6 . In this manner, theresin frame member 24 and thegas diffusion layer 22 c of thecathode 22 are combined into one piece by theimpregnation portion 26. - The electrode catalyst layers 20 a, 22 a are coated on both
surfaces gas diffusion layer 20 c of the anode and thegas diffusion layer 22 c joined to theresin frame member 24 are placed on bothsurfaces polymer electrolyte membrane 18, respectively. These components are subjected to hot pressing treatment to produce the membrane electrode assembly 10 (S5). - Accordingly, in the second embodiment, the same advantages as in the case of the first embodiment are obtained.
-
FIG. 8 is a diagram showing steps of a method of producing amembrane electrode assembly 10 according to a third embodiment of the present invention. - In the third embodiment, after the
intermediate layer 20 b is coated on thegas diffusion layer 20 c of the anode (S11), theelectrode catalyst layer 20 a is coated on theintermediate layer 20 b of thegas diffusion layer 20 c (S12). Further, after theintermediate layer 22 b is coated on thegas diffusion layer 22 c of the cathode (S13), theresin frame member 24 is joined to thegas diffusion layer 22 c (S14). The process of joining thegas diffusion layer 22 c to theresin frame member 24 is the same as in the cases of the first and second embodiments. - Further, the
electrode catalyst layer 22 a of the cathode is coated on thesurface 18 b of the solid polymer electrolyte membrane 18 (S15). Then, thegas diffusion layer 20 c of the anode and thegas diffusion layer 22 c of the cathode joined to theresin frame member 24 are placed on bothsurfaces polymer electrolyte membrane 18, respectively. These components are subjected to hot pressing treatment to produce the membrane electrode assembly 10 (S16). - Accordingly, in the third embodiment, the same advantages as in the cases of the first and second embodiments are obtained.
-
FIG. 9 is a cross sectional view showing a solid polymerelectrolyte fuel cell 62 including amembrane electrode assembly 60 according to a fourth embodiment of the present invention. The constituent elements of the solid polymerelectrolyte fuel cell 62 that are identical to those of the solid polymerelectrolyte fuel cell 12 including themembrane electrode assembly 10 according to the first embodiment are labeled with the same reference numerals, and descriptions thereof will be omitted. Likewise, also in fifth and subsequent embodiments described later, the constituent elements that are identical to those of the solid polymerelectrolyte fuel cell 12 including themembrane electrode assembly 10 according to the first embodiment are labeled with the same reference numerals, and descriptions thereof will be omitted. - In the
membrane electrode assembly 60, theanode 20 includes anelectrode catalyst layer 20 a joined to thesurface 18 a of the solidpolymer electrolyte membrane 18 and agas diffusion layer 20 c stacked on theelectrode catalyst layer 20 a. Thecathode 22 includes anelectrode catalyst layer 22 a joined to thesurface 18 b of the solidpolymer electrolyte membrane 18 and agas diffusion layer 22 c stacked on theelectrode catalyst layer 22 a. Though not shown, theelectrode catalyst layer 20 a and thegas diffusion layer 20 c may be provided through an intermediate layer (underlying layer). Likewise, theelectrode catalyst layer 22 a and thegas diffusion layer 22 c may be provided through an intermediate layer (underlying layer). - The
resin frame member 24 and thegas diffusion layer 22 c of thecathode 22 are combined into one piece by a firstresin impregnation portion 26 a, and theresin frame member 24 and thegas diffusion layer 20 c of theanode 20 are combined into one piece by a secondresin impregnation portion 26 b. - As shown in
FIG. 10 , the firstresin impregnation portion 26 a is formed over the entire circumference of thegas diffusion layer 22 c of thecathode 22. The width L1 on the long side of the firstresin impregnation portion 26 a (side extending in the direction indicated by the arrow B) is larger than the width L2 on the short side of the firstresin impregnation portion 26 a (side extending in the direction indicated by the arrow C) (L1>L2). - As shown in
FIG. 11 , the secondresin impregnation portion 26 b is formed over the entire circumference of thegas diffusion layer 20 c of theanode 20. The width L3 on the long side of the secondresin impregnation portion 26 b (side extending in the direction indicated by the arrow B) is larger than the width L4 on the short side of the secondresin impregnation portion 26 b (side extending in the direction indicated by the arrow C) (L3>L4). - As shown in
FIG. 9 , the secondresin impregnation portion 26 b is terminated at a position spaced outward of a first innercircumferential portion 24 c of theresin frame member 24 adjacent to thecathode 22 by the distance H. That is, the secondresin impregnation portion 26 b is not provided at a position overlapped with thecathode 22 in the stacking direction. - Next, a method of producing the
membrane electrode assembly 60 will be described below. - Firstly, as shown in
FIG. 12 , anMEA 64 having different sizes of components (stepped-type MEA) of themembrane electrode assembly 60 is produced. Specifically, the electrode catalyst layers 20 a, 22 a are coated on bothsurfaces polymer electrolyte membrane 18. Thegas diffusion layer 20 c is placed adjacent to thesurface 18 a of the solidpolymer electrolyte membrane 18, i.e., on theelectrode catalyst layer 20 a, and thegas diffusion layer 22 c is placed adjacent to thesurface 18 b of the solidpolymer electrolyte membrane 18, i.e., on theelectrode catalyst layer 22 a. These components are stacked together, and subjected to hot pressing treatment to produce theMEA 64. - In the meanwhile, the
resin frame member 24 is formed beforehand by an injection molding machine (not shown). Theresin frame member 24 is positioned in alignment with theMEA 64. Theresin frame member 24 has the first innercircumferential portion 24 c and a second innercircumferential portion 24 d. The end of thecathode 22 is positioned at the first innercircumferential portion 24 c, and the end of theanode 20 is positioned at the second innercircumferential portion 24 d. - A
first resin member 26 aa forming the firstresin impregnation portion 26 a is prepared at thecathode 22, and asecond resin member 26 bb forming the secondresin impregnation portion 26 b is prepared at theanode 20. Each of thefirst resin member 26 aa and thesecond resin member 26 bb has a frame shape, and is made of the same material as theresin frame member 24, for example. - The
resin frame member 24 uses resin material enforced by mixing a filler with the resin material. Thefirst resin member 26 aa and thesecond resin member 26 bb may be made of resin material which is not mixed with any filler. In the structure, using the robustresin frame member 24, theMEA 64 and theresin frame member 24 can be joined together. - Then, in the state where the
first resin member 26 aa and thesecond resin member 26 bb are placed over theMEA 64 and theresin frame member 24 and a load is applied to theMEA 64 and theresin frame member 24 through thefirst resin member 26 aa and thesecond resin member 26 bb, thefirst resin member 26 aa and thesecond resin member 26 bb are heated. As a heating method, any of laser welding, infrared welding, and impulse welding, etc. is adopted. - Thus, the
first resin member 26 aa and thesecond resin member 26 bb are melted by heating. Both of thegas diffusion layer 22 c of thecathode 22 and theresin frame member 24 are impregnated with the melted resin of thefirst resin member 26 aa, and both of thegas diffusion layer 20 c of theanode 20 and theresin frame member 24 are impregnated with the melted resin of thesecond resin member 26 bb. - Thus, as shown in
FIG. 9 , the firstresin impregnation portion 26 a is formed over thegas diffusion layer 22 c of thecathode 22 and theresin frame member 24, and the secondresin impregnation portion 26 b is formed over thegas diffusion layer 20 c of theanode 20 and theresin frame member 24 to produce themembrane electrode assembly 60. - In the fourth embodiment, the outer ends of the gas diffusion layers 22 c, 20 c of the
cathode 22 and theanode 20 and theresin frame member 24 are impregnated with resin, respectively, and formed integrally with the firstresin impregnation portion 26 a and the secondresin impregnation portion 26 b. - In the structure, in comparison with the case where the
resin frame member 24 is joined to thecathode 22 and theanode 20 by adhesion, the joining strength for joining theresin frame member 24 to thecathode 22 and theanode 20 is improved suitably, and it is possible to suppress occurrence of peeling or the like as much as possible. - Further, the width L1 on the long side of the first
resin impregnation portion 26 a is larger than the width L2 on the short side of the firstresin impregnation portion 26 a (L1>L2) (seeFIG. 10 ). Moreover, the width L3 on the long side of the secondresin impregnation portion 26 b is larger than the width L4 on the short side of the secondresin impregnation portion 26 b (L3>L4) (seeFIG. 11 ). Thus, further improvement in the joining strength for joining theresin frame member 24 to thecathode 22 and theanode 20 is achieved suitably, - Further, as shown in
FIG. 9 , the secondresin impregnation portion 26 b is terminated at a position spaced outward of the first innercircumferential portion 24 c of theresin frame member 24 adjacent to thecathode 22, by the distance H. In the range of the distance H, since theelectrode catalyst layer 22 a of thecathode 22 facing theanode 20 is not present, abnormal reaction does not occur. - For example, in a comparative example shown in
FIG. 13 , thegas diffusion layer 22 c of thecathode 22 and theresin frame member 24 are combined into one piece by a firstresin impregnation portion 27 a. Further, thegas diffusion layer 20 c of theanode 20 and theresin frame member 24 are combined into one piece by a secondresin impregnation portion 27 b. The secondresin impregnation portion 27 b extends inward of the end of the firstresin impregnation portion 27 a by the distance Ha. - In the comparative example, the
electrode catalyst layer 22 a of thecathode 22 is present in the range of the distance Ha where the secondresin impregnation portion 27 b is provided. In the structure, shortage of hydrogen occurs at theanode 20 in the range of the distance Ha, and abnormal reaction tends to occur at thecathode 22. - Specifically, by reactions of H2O→1/2O2+2H++2e−, C+2H2O→CO2+4H++4e−, and Pt→PT2++2e−, dissolution of corrosive Pt of the supporting carbon occurs, and consequently, the performance is lowered undesirably.
-
FIG. 14 is a cross sectional view showing main components of amembrane electrode assembly 70 according to a fifth embodiment of the present invention. - The
membrane electrode assembly 70 includes aresin frame member 72 joined to thecathode 22 and theanode 20. Afirst resin protrusion 74 a and asecond resin protrusion 74 b are formed integrally with theresin frame member 72 for combining theresin frame member 72 and thegas diffusion layer 22 c of thecathode 22 into one piece, and combining theresin frame member 72 and thegas diffusion layer 20 c of theanode 20 into one piece. - The
first resin protrusion 74 a is formed in a frame shape around the first innercircumferential portion 24 c, and thesecond resin protrusion 74 b is formed in a frame shape around the second innercircumferential portion 24 d. Preferably, thefirst resin protrusion 74 a has an inclined surface 74 as as an end surface opposite to the first innercircumferential portion 24 c, and the inclined surface 74 as is inclined in a direction spaced from theresin frame member 72. - Likewise, preferably, the
second resin protrusion 74 b has an inclined surface 74 bs as an end surface opposite to the second innercircumferential portion 24 d, and the inclined surface 74 bs is inclined in a direction spaced from theresin frame member 72. - The
first resin protrusion 74 a and thesecond resin protrusion 74 b are heated by a heating machine (not shown), and melted. By applying a load to thefirst resin protrusion 74 a and thesecond resin protrusion 74 b, the gas diffusion layers 22 c, 20 c are impregnated with the melted resin of thefirst resin protrusion 74 a and thesecond resin protrusion 74 b. In this manner, the firstresin impregnation portion 26 a and the secondresin impregnation portion 26 b are formed. Thus, in the fifth embodiment, the same advantages as in the case of the fourth embodiment are obtained. -
FIG. 15 is a cross sectional view showing main components of amembrane electrode assembly 80 according to a sixth embodiment of the present invention. - The
membrane electrode assembly 80 includes aresin frame member 82 joined to thecathode 22 and theanode 20. Theresin frame member 82 includes afirst resin member 84 a and asecond resin member 84 b for combining theresin frame member 82 and thegas diffusion layer 22 c of thecathode 22 into one piece, and combining theresin frame member 82 and thegas diffusion layer 20 c of theanode 20 into one piece. Thefirst resin member 84 a and thesecond resin member 84 b are formed integrally with theresin frame member 82 by insert molding beforehand. - The
first resin member 84 a and thesecond resin member 84 b are heated by a heating machine (not shown), and melted. By applying a load to thefirst resin member 84 a and thesecond resin member 84 b, the gas diffusion layers 22 c, 20 c are impregnated with the melted resin of thefirst resin member 84 a and thesecond resin member 84 b. In this manner, the firstresin impregnation portion 26 a and the secondresin impregnation portion 26 b are formed. Thus, in the sixth embodiment, the same advantages as in the case of the fourth and fifth embodiments are obtained. -
FIG. 16 is a cross sectional view showing amembrane electrode assembly 90 according to a seventh embodiment of the present invention. - The
membrane electrode assembly 90 includes aresin frame member 92 joined to thecathode 22 and theanode 20. Afirst resin protrusion 94 a and asecond resin protrusion 94 b are provided integrally with theresin frame member 92 for combining theresin frame member 92 and thegas diffusion layer 22 c of thecathode 22 into one piece, and combining theresin frame member 92 and thegas diffusion layer 20 c of theanode 20 into one piece. - The
first resin protrusion 94 a is formed in a frame shape around the first innercircumferential portion 24 c, and thesecond resin protrusion 94 b is formed in a frame shape around the second innercircumferential portion 24 d. - Each of the
first resin protrusion 94 a and thesecond resin protrusion 94 b has a rectangular shape in cross section. In effect, thefirst resin protrusion 94 a and thesecond resin protrusion 94 b are formed by eliminating the inclined surfaces 74 as, 74 bs of thefirst resin protrusion 74 a and thesecond resin protrusion 74 b in themembrane electrode assembly 70 according to the fifth embodiment. - In the seventh embodiment, the
first resin protrusion 94 a and thesecond resin protrusion 94 b are heated by a heating machine (not shown), and melted. By applying a load to thefirst resin protrusion 94 a and thesecond resin protrusion 94 b, the gas diffusion layers 22 c, 20 c are impregnated with the melted resin of thefirst resin protrusion 94 a and thesecond resin protrusion 94 b. In this manner, the firstresin impregnation portion 26 a and the secondresin impregnation portion 26 b are formed. - Thus, in the seventh embodiment, the same advantage as in the case of the fourth to sixth embodiments are obtained. Further, in particular, operation of producing the
first resin protrusion 94 a and thesecond resin protrusion 94 b can be carried out simply. -
FIG. 17 is a cross sectional view showing a solid polymerelectrolyte fuel cell 102 including amembrane electrode assembly 100 according to an eighth embodiment of the present invention. - In the
membrane electrode assembly 100, theresin frame member 24 and thegas diffusion layer 20 c of theanode 20 are combined into one piece by aresin impregnation portion 104. That is, theresin frame member 24 is joined only to theanode 20 which is larger than thecathode 22. - At the time of producing the
membrane electrode assembly 100, as shown inFIG. 18 , anMEA 106 having different sizes of components (stepped-type MEA) of themembrane electrode assembly 100 is produced. In the state where theresin frame member 24 and theMEA 106 are positioned with respect to each other, aresin member 104 a for forming theresin impregnation portion 104 is prepared. Theresin member 104 a has a frame shape, and uses resin material enforced by mixing a glass filler with the resin material. - Then, in the state where the
resin member 104 a is placed, and a load is applied to theMEA 106 and theresin frame member 24, theresin member 104 a is heated. Thus, theheated resin member 104 a is melted to form theresin impregnation portion 104 over thegas diffusion layer 20 c of theanode 20 and theresin frame member 24. In this manner, themembrane electrode assembly 100 is produced. - In the eighth embodiment, when the
resin member 104 a is heated, and melted, the glass filler does not enter thegas diffusion layer 20 c. Therefore, theresin member 104 a does not directly contact the solidpolymer electrolyte membrane 18. - Further, when the
resin member 104 a is melted at high temperature, thegas diffusion layer 20 c and theelectrode catalyst layer 20 a, and in certain cases, anintermediate layer 20 b are present between the solidpolymer electrolyte membrane 18 and theresin member 104 a. Thus, thermal effect on the solidpolymer electrolyte membrane 18 is reduced. - Accordingly, as the
resin member 104 a, it become possible to adopt resin mixed with a glass filler, and use resin having high melting temperature. Thus, the resin used for theresin member 104 a can be adopted from a wide variety of selection advantageously.
Claims (13)
1. A fuel cell membrane electrode assembly comprising:
a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane, the first electrode and the second electrode each including an electrode catalyst layer and a gas diffusion layer, an outer size of the first electrode being smaller than an outer size of the second electrode,
the membrane electrode assembly further comprising:
a resin frame member provided around the solid polymer electrolyte membrane; and
an impregnation portion for joining the resin frame member and at least one of an outer marginal portion of the first electrode and an outer marginal portion of the second electrode together, by impregnation of resin in a thickness direction of the resin frame member.
2. The fuel cell membrane electrode assembly according to claim 1 , wherein in the impregnation portion, the outer marginal portion of the first electrode is impregnated with an inner circumferential portion of the resin frame member, and the inner circumferential portion of the resin frame member is joined to the first electrode.
3. The fuel cell membrane electrode assembly according to claim 2 , wherein the resin frame member includes an inner extension, and a thickness of the inner extension is smaller than a thickness of the outer end of the resin frame member; and
the inner extension has the inner marginal portion for impregnation of the outer marginal portion of the first electrode.
4. The fuel cell membrane electrode assembly according to claim 1 , wherein an outer end of the gas diffusion layer of the first electrode and an outer end of the gas diffusion layer of the second electrode are impregnated with resin such that resin impregnation portions as the impregnation portion joining the membrane electrode assembly and the resin frame member together are provided.
5. The fuel cell membrane electrode assembly according to claim 4 , wherein the resin impregnation portions are provided over entire circumferences of the outer ends of the gas diffusion layers, respectively.
6. The fuel cell membrane electrode assembly according to claim 4 , wherein the resin impregnation portions include a frame shaped first resin member placed over an entire circumference of the gas diffusion layer of the first electrode and a frame shaped second resin member (placed over an entire circumference of the gas diffusion layer of the second electrode.
7. The fuel cell membrane electrode assembly according to claim 4 , wherein the resin impregnation portions include:
a frame shaped first resin protrusion provided integrally with the resin frame member, and placed over an entire circumference of the gas diffusion layer of the first electrode; and
a frame shaped second resin protrusion provided integrally with the resin frame member, and placed over an entire circumference of the gas diffusion layer of the second electrode.
8. The fuel cell membrane electrode assembly according to claim 1 , wherein an outer end of the gas diffusion layer of the second electrode is impregnated with resin to form a resin impregnation portion as the impregnation portion joining the membrane electrode assembly and the resin frame member together.
9. The fuel cell membrane electrode assembly according to claim 8 , wherein the resin impregnation portion is provided over an entire circumference of the outer end of the gas diffusion layer.
10. The fuel cell membrane electrode assembly according to claim 8 , wherein the resin impregnation portion includes a frame shaped resin member placed over an entire circumference of the gas diffusion layer of the second electrode.
11. A method of producing a fuel cell membrane electrode assembly, the membrane electrode assembly comprising a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane, the first electrode and the second electrode each including an electrode catalyst layer and a gas diffusion layer, an outer size of the first electrode being smaller than an outer size of the second electrode,
the method comprising the steps of:
forming the first electrode and the second electrode on both sides of the solid polymer electrolyte membrane;
forming a resin frame member; and
overlapping an outer marginal portion of the first electrode and an inner marginal portion of the resin frame member with each other and heating the overlapped portions of the first electrode and the resin frame member to impregnate the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member around the solid polymer electrolyte membrane.
12. A method of producing a fuel cell membrane electrode assembly, the membrane electrode assembly comprising a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane, the first electrode and the second electrode each including an electrode catalyst layer and a gas diffusion layer, an outer size of the first electrode being smaller than an outer size of the second electrode,
the method comprising the steps of:
overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of a resin frame member with each other and heating the overlapped portions of the gas diffusion layer of the first electrode and the resin frame member to impregnate the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode;
forming the electrode catalyst layers on both surfaces of the solid polymer electrolyte membrane; and
combining the gas diffusion layer of the first electrode joined to the resin frame member and the gas diffusion layer of the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
13. A method of producing a fuel cell membrane electrode assembly, the membrane electrode assembly comprising a solid polymer electrolyte membrane and a first electrode and a second electrode provided on both sides of the solid polymer electrolyte membrane, the first electrode and the second electrode each including an electrode catalyst layer and a gas diffusion layer, an outer size of the first electrode being smaller than an outer size of the second electrode,
the method comprising the steps of:
overlapping an outer marginal portion of the gas diffusion layer of the first electrode and an inner marginal portion of a resin frame member with each other and heating the overlapped portions of the gas diffusion layer of the first electrode and the resin frame member to impregnate the outer marginal portion of the first electrode with the inner marginal portion of the resin frame member and join the resin frame member to the first electrode;
forming the electrode catalyst layer on the gas diffusion layer of the second electrode and forming the electrode catalyst layer of the first electrode on one side of the solid polymer electrolyte membrane; and
combining the first electrode joined to the resin frame member and the second electrode on both sides of the solid polymer electrolyte membrane into one piece.
Priority Applications (1)
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US15/857,807 US10658683B2 (en) | 2011-04-01 | 2017-12-29 | Method for producing electrolyte membrane electrode assembly for fuel cells |
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JP2011082175 | 2011-04-01 | ||
JP2011-082175 | 2011-04-01 | ||
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JP2011-134851 | 2011-06-17 | ||
PCT/JP2012/057507 WO2012137609A1 (en) | 2011-04-01 | 2012-03-23 | Electrolyte membrane-electrode assembly for fuel cells, and method for producing same |
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PCT/JP2012/057507 A-371-Of-International WO2012137609A1 (en) | 2011-04-01 | 2012-03-23 | Electrolyte membrane-electrode assembly for fuel cells, and method for producing same |
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US14/008,193 Abandoned US20140017590A1 (en) | 2011-04-01 | 2012-03-23 | Electrolyte membrane-electrode assembly for fuel cells, and method for producing same |
US15/857,807 Active 2032-06-12 US10658683B2 (en) | 2011-04-01 | 2017-12-29 | Method for producing electrolyte membrane electrode assembly for fuel cells |
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JP (1) | JP5681792B2 (en) |
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Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160190610A1 (en) * | 2013-08-08 | 2016-06-30 | Nissan Motor Co., Ltd. | Membrane electrode assembly with frame, fuel cell single cell, and fuel cell stack |
WO2017055815A1 (en) * | 2015-09-30 | 2017-04-06 | Intelligent Energy Limited | Fuel cell sub-assembly |
US10637077B2 (en) | 2018-03-02 | 2020-04-28 | Honda Motor Co., Ltd. | Frame equipped membrane electrode assembly and fuel cell |
US10665873B2 (en) | 2015-10-21 | 2020-05-26 | Honda Motor Co., Ltd. | Resin frame equipped membrane electrode assembly for fuel cell and method of producing the same |
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US20210226241A1 (en) * | 2020-01-17 | 2021-07-22 | Toyota Jidosha Kabushiki Kaisha | Fuel cell and method of manufacturing fuel cell |
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US11374240B2 (en) | 2019-09-30 | 2022-06-28 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
US11437632B2 (en) | 2019-09-30 | 2022-09-06 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
US11600831B2 (en) | 2019-09-30 | 2023-03-07 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6125903B2 (en) * | 2013-05-20 | 2017-05-10 | 本田技研工業株式会社 | Fuel cell |
JP6090791B2 (en) * | 2013-11-06 | 2017-03-08 | 本田技研工業株式会社 | Electrolyte membrane / electrode structure with resin frame for fuel cells |
DE102014205035A1 (en) * | 2014-03-18 | 2015-09-24 | Volkswagen Ag | Method for producing a membrane-electrode assembly, membrane-electrode assembly, fuel cell and motor vehicle with fuel cell |
JP6144650B2 (en) * | 2014-06-27 | 2017-06-07 | 本田技研工業株式会社 | Manufacturing method of fuel cell |
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JP6442393B2 (en) * | 2015-10-22 | 2018-12-19 | 本田技研工業株式会社 | Electrolyte membrane / electrode structure with resin frame for fuel cells |
JP6843730B2 (en) * | 2016-11-17 | 2021-03-17 | 本田技研工業株式会社 | Fuel cell and its operation method |
DE102016224611B4 (en) * | 2016-12-09 | 2021-07-08 | Audi Ag | Fuel cell structure and process for its manufacture |
KR20200072197A (en) | 2018-12-12 | 2020-06-22 | 현대자동차주식회사 | Elastomer cell frame for fuel cell and manufacturing method thereof and unit cell comprising thereof |
DE102019203249A1 (en) * | 2019-03-11 | 2020-09-17 | Audi Ag | Fuel cell structure, fuel cell system and fuel cell vehicle |
KR20210015384A (en) * | 2019-08-02 | 2021-02-10 | 현대자동차주식회사 | Elastomeric cell frame for fuel cell and manufacturing method thereof and unit cell comprising thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010123491A (en) * | 2008-11-21 | 2010-06-03 | Nissan Motor Co Ltd | Apparatus for manufacturing membrane electrode assembly |
JP2010192392A (en) * | 2009-02-20 | 2010-09-02 | Sumitomo Chemical Co Ltd | Porous membrane complex for fuel cell, electrolyte membrane-electrode-porous membrane complex for fuel cell, and manufacturing method of them |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1548164A1 (en) | 2002-09-30 | 2005-06-29 | Toray Industries, Inc. | Flame-resistant acrylic fiber nonwoven fabric, carbon fiber nonwoven fabric, and method for production thereof |
JP2005085594A (en) * | 2003-09-09 | 2005-03-31 | Fuji Electric Holdings Co Ltd | Solid polymer electrolyte type fuel cell and manufacturing method of the same |
US20060127738A1 (en) | 2004-12-13 | 2006-06-15 | Bhaskar Sompalli | Design, method and process for unitized mea |
JP2006210060A (en) * | 2005-01-26 | 2006-08-10 | Honda Motor Co Ltd | Fuel cell |
JP4931103B2 (en) * | 2005-01-31 | 2012-05-16 | 内山工業株式会社 | Fuel cell components |
JP5194346B2 (en) | 2005-08-31 | 2013-05-08 | 日産自動車株式会社 | Electrolyte membrane-electrode assembly |
JP2007109576A (en) | 2005-10-14 | 2007-04-26 | Japan Gore Tex Inc | Membrane electrode assembly and solid polymer fuel cell |
JP5184833B2 (en) * | 2007-07-18 | 2013-04-17 | 株式会社東芝 | Method for producing gas diffusion substrate for fuel cell |
JP2010186627A (en) * | 2009-02-12 | 2010-08-26 | Toyota Motor Corp | Fuel battery |
-
2012
- 2012-03-23 JP JP2013508809A patent/JP5681792B2/en active Active
- 2012-03-23 DE DE112012001547T patent/DE112012001547T5/en not_active Withdrawn
- 2012-03-23 CN CN201280016093.6A patent/CN103443981B/en active Active
- 2012-03-23 WO PCT/JP2012/057507 patent/WO2012137609A1/en active Application Filing
- 2012-03-23 US US14/008,193 patent/US20140017590A1/en not_active Abandoned
-
2017
- 2017-12-29 US US15/857,807 patent/US10658683B2/en active Active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010123491A (en) * | 2008-11-21 | 2010-06-03 | Nissan Motor Co Ltd | Apparatus for manufacturing membrane electrode assembly |
JP2010192392A (en) * | 2009-02-20 | 2010-09-02 | Sumitomo Chemical Co Ltd | Porous membrane complex for fuel cell, electrolyte membrane-electrode-porous membrane complex for fuel cell, and manufacturing method of them |
Non-Patent Citations (2)
Title |
---|
Translation of JP 2010-123491 * |
Translation of JP 2010-192392 * |
Cited By (15)
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US11056694B2 (en) | 2015-09-30 | 2021-07-06 | Intelligent Energy Limited | Fuel cell sub-assembly |
US10665873B2 (en) | 2015-10-21 | 2020-05-26 | Honda Motor Co., Ltd. | Resin frame equipped membrane electrode assembly for fuel cell and method of producing the same |
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US11374240B2 (en) | 2019-09-30 | 2022-06-28 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
US11437632B2 (en) | 2019-09-30 | 2022-09-06 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
US11600831B2 (en) | 2019-09-30 | 2023-03-07 | Toyota Jidosha Kabushiki Kaisha | Fuel-cell unit cell |
US20210226241A1 (en) * | 2020-01-17 | 2021-07-22 | Toyota Jidosha Kabushiki Kaisha | Fuel cell and method of manufacturing fuel cell |
US11588167B2 (en) * | 2020-01-17 | 2023-02-21 | Toyota Jidosha Kabushiki Kaisha | Fuel cell and method of manufacturing fuel cell |
Also Published As
Publication number | Publication date |
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US10658683B2 (en) | 2020-05-19 |
JPWO2012137609A1 (en) | 2014-07-28 |
CN103443981B (en) | 2016-08-17 |
US20180145359A1 (en) | 2018-05-24 |
WO2012137609A1 (en) | 2012-10-11 |
DE112012001547T5 (en) | 2013-12-24 |
JP5681792B2 (en) | 2015-03-11 |
CN103443981A (en) | 2013-12-11 |
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