JP5181969B2 - Fuel cell - Google Patents

Description

  The present invention relates to a fuel cell in which a gasket is integrally formed with a plurality of fuel cells to form one module, and a plurality of the modules are stacked to form a fuel cell stack.

  A fuel cell of a polymer electrolyte fuel cell has a membrane electrode assembly (MEA) formed from an ion-permeable electrolyte membrane and an anode-side and cathode-side catalyst layer sandwiching the electrolyte membrane. In addition, a gas flow path layer made of a porous body for providing fuel gas or oxidant gas and collecting electricity generated by an electrochemical reaction and a separator are arranged on both sides of the membrane electrode assembly. There is also a cell configuration in which a gas diffusion layer (GDL: Gas Diffusion Layer) is interposed between the membrane electrode assembly and the porous body. An actual fuel cell stack is formed by stacking and stacking a number of fuel cell cells according to required power.

  In the fuel cell having the above structure, a gasket for sealing a fluid such as a fuel gas and an oxidant gas supplied to the membrane electrode assembly and a coolant such as cooling water for suppressing the temperature rise of the cell is attached to the membrane electrode assembly. Formed on the periphery of the body and the porous body. In conventional fuel cells, a gasket is formed for each fuel cell, and stacking is performed after stacking a predetermined number of fuel cells each having a gasket on the periphery of the membrane electrode assembly and the porous body. . This gasket molding is generally performed by injection molding. More specifically, either the anode side or the cathode side separator is accommodated in the cavity of the molding die, and then the anode side or cathode serving as a gas flow path. One of the porous bodies on the side, and then the membrane electrode assembly (MEA) or the electrode body (MEGA) if it has a gas diffusion layer, and then the other porous body on the anode side or cathode side Thus, gasket molding is performed by injecting resin into the gasket forming cavity at the periphery of the membrane electrode assembly and the porous body.

  In this separator, in addition to the gas channel grooves and cooling water channel grooves formed on both sides of the separator, a plate in which a channel is formed between two plates made of titanium or stainless steel, for example, is interposed. There are layered three-layer separators. With regard to this three-layer separator, there is also a mode in which the cooling medium flow path is formed by projecting ribs that define a large number of dimples and flow paths from one of the two plates, using an intermediate layer as a resin frame material. Exists. The separator having the three-layer structure is either the anode side or the cathode side separator of the cell itself, and at the same time, is the other separator on the anode side or the cathode side of the adjacent cell in the stacked posture. When this three-layer structure separator is applied, a gas flow path layer made of a porous body such as expanded metal or foamed sintered body is disposed between the separator and the gas diffusion layer.

  As described above, the conventional fuel cell stack is stacked by stacking fuel cells in which gaskets are formed. For example, in the case where a fuel cell stack is formed by stacking about 200 to 400 fuel cells, each fuel cell is provided with a unique voltage sensor, and the cell voltage drops below a predetermined value. When the cell is specified, the fuel cell is extracted from the stack and replaced with another fuel cell.

  However, it is easy to understand that the task of releasing stacking from a fuel cell stack in which a large number of fuel cells are stacked, extracting only the fuel cells that need replacement and replacing them with separate cells is extremely complicated, Improvements are screamed in the field.

  By the way, the electrolyte membrane constituting the membrane electrode assembly is in a state of fluid communication with the outside through the gas diffusion layer having pores and the porous body. This electrolyte membrane greatly deteriorates its characteristics due to contamination of different materials. Therefore, in the present situation where all the fuel cells are individually injection molded and then assembled, all the fuel cells are subjected to injection molding (for example, contamination by volatile gas) or assembled. In addition, there is a risk that the electrolyte membrane is contaminated by different materials. From this point of view as well, review and improvement of the manufacturing method of forming a fuel cell stack by forming a gasket by injection molding or the like for each fuel cell, and a fuel cell stack made by this manufacturing method Improvement of the structure is inevitable, and development for that is an urgent issue. In particular, as the stationary type of houses, etc., or the mobile type of hybrid vehicles, electric vehicles, etc., the spread of fuel cells has been steadily expanding, and it is necessary to satisfy both performance improvement and productivity improvement. In view of this, it is extremely important to develop a fuel cell that can effectively solve the aforementioned urgent problems.

  Turning to the conventional published technique, Patent Document 1 discloses a technique relating to a method of manufacturing a fuel cell for the purpose of improving the assemblability and decomposability of the fuel cell. However, this technique also forms a gasket for each fuel cell, stacks the cells, and stacks them, so that the above-described problems cannot be effectively solved.

JP 2008-123883 A

  The present invention has been made in view of the above-described problems, and can effectively prevent foreign materials from being contaminated (attached, etc.) to the electrolyte membrane in each fuel cell forming the fuel cell stack. It is an object of the present invention to provide a fuel cell that is excellent in efficiency during maintenance such as extracting and replacing a fuel cell having degraded performance from the fuel cell stack.

  In order to achieve the above object, a fuel cell according to the present invention includes a membrane electrode assembly, an anode-side and cathode-side porous body that serves as a gas flow path for sandwiching the membrane-electrode assembly, and one of the anode-side and cathode-side. A plurality of fuel cells comprising a plurality of fuel cells are laminated, and a gasket formed integrally with the periphery of each laminated membrane electrode assembly and porous body is formed to form a single module comprising a plurality of fuel cells. A plurality of the modules are stacked to form a fuel cell stack.

  The fuel cell of the present invention is formed by forming a plurality of fuel cells as one module and stacking a plurality of the modules to form a fuel cell stack. In one module, for example, a plurality of fuels are formed in a mold. A battery cell (constituent member) is accommodated and injection molded to form a gasket in which each cell is formed at once, and a plurality of cells are connected by the integrally molded gasket.

  Therefore, for example, when one module is composed of 30 fuel cells, the membrane electrode assembly of the 28 fuel cells inside other than both ends is completely cut off from the outside during injection molding. In other words, it is possible to prevent the foreign material from being contaminated with the electrolyte membrane constituting the membrane electrode assembly.

  Further, in maintenance after the fuel cell is put into service, the replacement can be performed not in units of cells but in units of modules. That is, one module has a posture in which cells cannot be separated by an integrally molded gasket, and adjacent modules are only in contact with each other in a separable manner (a seal structure is formed at the contact portion). Further, it becomes easy to remove a module having a cell having a degraded performance, and it is easy to regenerate the fuel cell stack.

  There are various scales of modules constituting the fuel cell (fuel cell stack). For example, in the case where 300 fuel cells are stacked to constitute one fuel cell, the range is about 2 to 50 units. One module can be configured with the cell radix. In the case where a single module is formed by a plurality of fuel cells and a plurality of the modules are stacked to form a single fuel cell stack, this module can also be referred to as a multi-cell 1-module fuel cell or the like. .

  The fuel cell constituting this module is composed of a membrane electrode assembly (MEA), a porous body on the anode side and cathode side forming a gas flow path layer, and a separator on either the anode side or the cathode side. Has been. In addition, the form which the gas diffusion layer which consists only of a current collection layer (MPL) and a diffusion layer base material, or a current collection layer may interpose between a membrane electrode assembly and a porous body may be sufficient.

  Here, the porous body is made of an expanded metal or a metal fired sintered body, and in this fired sintered body, a metal material having excellent corrosion resistance such as titanium, stainless steel, copper, nickel or the like is preferably used. For example, it may be a foam in which chromium carbide or iron-chromium carbide is dispersed in stainless steel.

  Further, as described above, the separator is, for example, a separator having a three-layer structure, and two metal plates made of a conductive metal (stainless steel, titanium, etc.) and a cooling water flow path formed of a metal material therebetween. Examples include a configuration in which an intermediate layer is interposed, or a configuration in which a frame material made of a resin material is used as an intermediate layer, and a large number of dimples or flow path defining ribs protrude from one plate of two metal plates. be able to. In the form having a large number of dimples in the intermediate layer, the cooling water flows from the supply manifold to the drainage manifold while forming a turbulent flow in the dimples, thereby cooling the membrane electrode assembly.

  Here, as the material of the gasket formed on the periphery of the membrane electrode assembly and the porous body by injection molding or the like, butyl rubber, urethane rubber, silicone RTV rubber, methanol-resistant epoxy resin, epoxy modified A silicone resin, a silicone resin, a fluororesin, a hydrocarbon resin, etc. can be mentioned.

  According to the fuel cell of the present invention described above, so-called multi-cell 1 modules are stacked to form a fuel cell stack, so that the electrolyte membranes of most fuel cells constituting the fuel cell stack are different in the manufacturing process. It is possible to effectively prevent contamination with the material. Furthermore, the maintenance efficiency is remarkably improved by extracting the fuel cell having a poor performance in units of modules including the cell. In addition, according to the rule of thumb of the present inventors, the performance degradation of the fuel cell is that the performance degradation of a plurality of cells including neighboring cells is lower than the performance degradation of only one cell, The fact that performance degradation sites in the cells tend to be almost the same in each cell has been specified, and even from this fact, even more efficient maintenance can be realized by extracting modules. be able to.

  In another embodiment of the fuel cell according to the present invention, the fuel cell includes a plurality of manifolds through which at least one of fuel gas, oxidant gas, and cooling water flows. In addition, separators are disposed at both ends of the module, and an endless first sealing material surrounding the manifold is interposed between the separators of adjacent modules.

  In this embodiment, a separator having a three-layer structure, for example, is disposed on both ends (both sides) of a module, and the endless shape is formed between adjacent modules and around a fluid circulation manifold formed on both sides. The sealing material (first sealing material) is arranged.

  Here, the first sealing material is made of, for example, an O-ring made of a metal material (the shape of which is circular, rectangular, square, etc.) or a ring made of a standard resin material, and a plurality of modules are stacked and stacked. At this time, the sealing material is appropriately crushed so that a fluid seal structure can be formed around the manifold.

  Each module has a structure with separators at both ends, and a structure in which a sealing material is interposed between adjacent separators, so that the surroundings of the module to be removed by removing stacking during maintenance The maintenance efficiency can be further improved by taking out the sealing material and the module and stacking them by incorporating a new module and the sealing material. In addition, since a new sealing structure can be formed between the modules with a new sealing material during maintenance, the sealing performance of the fuel cell due to maintenance is not reduced.

  Further, in this embodiment of the fuel cell, endless concave grooves are formed at corresponding positions on the opposing surfaces of the separators of the adjacent modules and around the manifold, and the adjacent modules are connected to each other. In the stacked posture, a part or all of the first sealing material may be accommodated in an endless space defined by both concave grooves.

  In the present embodiment, endless grooves are formed around the manifolds on the opposing surfaces of the separators of the adjacent modules and corresponding positions, and both grooves are stacked in a posture in which the modules are stacked. By forming an endless space at and containing the sealing material described above in this space, the positioning of the sealing material is facilitated, and displacement of the sealing material can be prevented during stacking.

  Furthermore, when the contained sealing material is completely crushed by the compressive force during stacking and adjacent separators are in surface contact with each other, a series flow of current generated in the stacking direction of each module (during current collection) Flow).

  In a preferred embodiment of the fuel cell according to the present invention, the periphery of the separator is also embedded in the gasket, and the gasket is continuous in one module.

  In this embodiment, the peripheral edge of the separator that has been exposed to the outside is completely surrounded by the gasket so that electrical insulation can be ensured between the separator and the outside. In the fuel cell having the conventional structure, the stack is accommodated in a case made of an insulating material such as resin, so that the insulation between the separator and the outside is secured.

  According to the present embodiment, the separator of each fuel cell constituting the module is completely embedded in the gasket, so that all the separators constituting the fuel cell stack are completely insulated from the outside by the gasket. Can be formed. Therefore, the case of the conventional insulating material can be dispensed with, and the fuel cell stack can be further reduced in size and weight.

  Furthermore, in another embodiment of the fuel cell according to the present invention, an endless second sealing material having elasticity is interposed between the opposing end surfaces of the adjacent modules and on the periphery of the end surfaces. It is what has been.

  The gas diffusion layer (GDL) constituting the fuel cell has elasticity, and is formed slightly thick in the cell stacking direction before stacking. When the stack is stacked, the gas diffusion layer is elastically deformed and compressed. As a result, a design is made such that the compressive force during stacking is applied to the membrane electrode assembly.

  By the way, when a plurality of fuel cells are integrally connected with a gasket to form one module, a thicker gas diffusion layer is stacked in the number of cells constituting the module before stacking. On the other hand, since the end portion of the module is fixed with a gasket, the central region of the module bulges outward, so-called a drum shape.

  When the drum-shaped modules whose center swells outward and whose peripheral edge falls are stacked, both modules abut on the central side, and a gap is formed in the area where the peripheral manifold is formed. It is easy to understand that the surrounding fluid sealability cannot be secured.

  Therefore, in the present embodiment, by providing an elastic sealing material (second sealing material) around the manifold between the modules, the above-described deterioration in sealing performance that may occur in the case of a multi-cell 1 module is effectively suppressed. To do. In addition, this 2nd sealing material can further improve the sealing performance in the module connection part of a fuel cell stack by using together with a 1st sealing material.

  As can be understood from the above description, according to the fuel cell of the present invention, a plurality of fuel cells are formed as an integrated module by an integrally molded gasket, and a plurality of modules are stacked to form a fuel cell stack. Thus, most of the electrolyte membranes of the fuel cells constituting the fuel cell stack can be effectively protected from being contaminated with different materials during the manufacturing process of the fuel cells. Furthermore, instead of removing a fuel cell that has deteriorated in performance alone, after removing stacking, it is removed in units of modules including one or more defective fuel cells and replaced with a new module. As a result, maintenance efficiency can be significantly improved. In addition, the seal around the manifold between the modules is excellent, and in the case where the separator is embedded in the gasket, the fuel cell is further excellent in electrical insulation from the outside.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a module in which a plurality of fuel cells are integrated with a gasket formed integrally. In this module 100, for example, 10 to 50 fuel cells 10,... Are stacked, and the gasket 8 is integrally formed.

  Each fuel cell 10 includes one separator 7 having a three-layer structure (in the figure, an anode-side separator), an anode-side porous body 6, a membrane electrode assembly 1, and cathode-side and anode-side gas diffusion layers. 2 and 3, and a cathode-side porous body 5. In addition to the illustrated example, a fuel cell that does not include the gas diffusion layers 2 and 3 may be used.

  Here, the electrolyte membrane constituting the membrane electrode assembly 1 is, for example, a fluorine ion exchange membrane having a sulfonic acid group or a carbonyl group, a substituted phenylene oxide, a sulfonated polyaryletherketone, a sulfonated polyarylethersulfone, a sulfone. It is formed from a non-fluorine polymer such as fluorinated phenylene sulfide.

  The catalyst layer is a mixture of a conductive carrier (particulate carbon carrier, etc.) on which a catalyst is supported, an electrolyte, and a dispersion solvent (organic solvent) to produce a catalyst solution (catalyst ink). A catalyst layer is formed by stretching a film on a substrate such as an electrolyte membrane or a gas diffusion layer in a layer shape with a coating blade to form a coating film, and drying in a hot air drying furnace or the like. Here, the electrolyte forming the catalyst solution is a proton conductive polymer, an ion exchange resin having a skeleton of an organic fluorine-containing polymer, such as a perfluorocarbon sulfonic acid resin, a sulfonated polyether ketone, a sulfonated polyether. Sulfonated plastic electrolytes such as sulfone, sulfonated polyetherethersulfone, sulfonated polysulfone, sulfonated polysulfide, sulfonated polyphenylene, sulfoalkylated polyetheretherketone, sulfoalkylated polyethersulfone, sulfoalkylated polyetherethersulfone And sulfoalkylated plastic electrolytes such as sulfoalkylated polysulfone, sulfoalkylated polysulfide, and sulfoalkylated polyphenylene. Examples of commercially available materials include Nafion (registered trademark, manufactured by DuPont) and Flemion (registered trademark, manufactured by Asahi Glass Co., Ltd.). Examples of the dispersion solvent include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, and diethylene glycol, acetone, methyl ethyl ketone, dimethylformamide, dimethylimidazolidinone, dimethyl sulfoxide, dimethylacetamide, and N-methylpyrrolidone. , Propylene carbonate, esters such as ethyl acetate and butyl acetate, and various aromatic or halogen solvents, and these can be used alone or as a mixed solution. Furthermore, regarding a conductive carrier carrying a catalyst, examples of the conductive carrier include carbon materials such as carbon black, carbon nanotubes, and carbon nanofibers, and carbon compounds typified by silicon carbide. As this catalyst (metal catalyst), for example, any one of platinum, platinum alloy, palladium, rhodium, gold, silver, osmium, iridium, etc. can be used, preferably platinum or platinum alloy is used. It is good to do. Further, examples of the platinum alloy include platinum, aluminum, chromium, manganese, iron, cobalt, nickel, gallium, zirconium, molybdenum, ruthenium, rhodium, palladium, vanadium, tungsten, rhenium, osmium, iridium, titanium, and lead. An alloy with at least one of them can be mentioned.

  The gas diffusion layers 2 and 3 are each composed of a diffusion layer base material and a current collecting layer (MPL). The diffusion layer base material is not particularly limited as long as it has a low electrical resistance and can collect current. For example, those mainly composed of conductive inorganic substances can be mentioned. Examples of the conductive inorganic substances include calcined bodies from polyacrylonitrile, calcined bodies from pitch, graphite and expanded graphite. Examples thereof include carbon materials, nanocarbon materials thereof, stainless steel, molybdenum, and titanium. Further, the form of the conductive inorganic substance of the diffusion layer base material is not particularly limited. For example, the conductive inorganic substance is used in the form of fibers or particles, but is an inorganic conductive fiber from the viewpoint of gas permeability, and particularly carbon fiber. Is preferred. As the diffusion layer substrate using inorganic conductive fibers, a woven fabric or non-woven fabric structure can be used, and examples thereof include carbon paper and carbon cloth. The woven fabric is not particularly limited, such as plain weaving, crest weaving, and binding weaving, and examples of the nonwoven fabric include those made by a papermaking method, a needle punching method, and a water jet punching method. Further, examples of the carbon fiber include phenol-based carbon fiber, pitch-based carbon fiber, polyacrylonitrile (PAN) -based carbon fiber, and rayon-based carbon fiber. Furthermore, the current collecting layer serves as an electrode for collecting electrons from the catalyst layer on the anode side and the cathode side. Platinum, palladium, ruthenium, rhodium, iridium, gold, silver, copper, and these are conductive materials. Or a conductive carbon material.

  Although not shown, in the exposed area where the electrolyte membrane is not in close contact with the catalyst layer at the periphery of the catalyst layer, fuzz protruding from the gas diffusion layer is prevented from sticking into the electrolyte membrane, Furthermore, the protective polymer film which has the effect which reinforces an electrolyte membrane with respect to the gasket by which injection molding is carried out is adhere | attached. This protective polymer film is made of polytetrafluoroethylene, PVDF (polyvinyl fluoride), polyethylene, polyethylene naphthalate (PEN), polycarbonate, polyphenylene ether (PPE), polypropylene, polyester, polyamide, copolyamide, polyamide elastomer, polyimide, It is formed from polyurethane, polyurethane elastomer, silicone, silicon rubber, silicon-based elastomer or the like.

  The porous bodies 5 and 6 can be formed from expanded metal or a metal foam sintered body. For example, a porous body made of a metal material foam sintered body excellent in corrosion resistance such as titanium, stainless steel, copper, nickel, etc. is a gas. A flow path layer is formed.

  In the illustrated module 100, for example, fuel cells 10,... Corresponding to the number of constituent bases are accommodated in a mold (not shown), and a resin 8 is injected into the cavity in that posture to form a gasket 8. The module 100 is formed integrally.

  The gasket 8 is formed of a resin material such as butyl rubber, urethane rubber, silicone RTV rubber, methanol-resistant epoxy resin, epoxy-modified silicone resin, silicone resin, fluorine resin, or hydrocarbon resin.

  In the illustrated example, an endless rib 8a for sealing that surrounds the manifold M is provided at the upper end of the gasket 8, and when the modules 100 are stacked and stacked, the rib 8a can be crushed to form a sealing structure. It has become.

  FIG. 1 is a cross section taken through a fuel gas supply manifold M and an exhaust manifold M, for example, and each fuel cell 10 constituting the module 100 is fluid in the stacking direction in a stacking posture. A communicating manifold M is formed. FIG. 1 shows a structure in which the fuel gas supplied from the manifold M is provided to the anode-side porous body 6 via the gas flow path 7a in the separator 7 having a three-layer structure. Therefore, in another cross section, a manifold for providing the oxidizing gas to the porous body 5 on the cathode side is formed.

  The separator 7 having a three-layer structure is formed by interposing an intermediate layer 73 in which a cooling water passage is formed of a metal material between metal plates 71 and 72 made of stainless steel or titanium. It is also possible to adopt a form in which a frame material made of a resin material is used as an intermediate layer, and a large number of dimples or ribs for channel definition protrude from one of the two metal plates.

  For example, when the module 100 shown in FIG. 1 is composed of 20 fuel cells 10,... And the fuel cell stack is composed of 300 fuel cells 10,. A fuel cell stack is formed by stacking 15 illustrated modules 100 and stacking them.

  As is apparent from the figure, for example, in injection molding, most of the electrolyte membranes of the fuel cells 10,... Constituting the module 100 are made in contact with an external dissimilar material because a plurality of cells are laminated. Therefore, it is possible to prevent volatile gases and the like from being contaminated particularly during injection molding, and further prevent contamination of foreign materials and the like floating during the process of stacking cells.

  FIG. 2 is a modification of FIG. 1 and shows a module 200 in which the gasket 8A has a structure in which a separator 7 having a three-layer structure is completely embedded.

  According to this module 200, the end of the separator 7 can be completely insulated from the outside. For example, even if there is no case made of an insulating resin for housing a conventional fuel cell stack, the electric insulation of the fuel cell stack Can be secured.

FIG. 3 shows still another embodiment of the module.
In this module 300, as shown in the figure, two fuel cells 20 and 20 are integrated with a gasket 8, and a separate separator 7A is arranged on the other side not including the separator 7A having a three-layer structure ( Separators 7A and 7A are disposed at both ends of the module 300). An endless concave groove 7Aa in which a part of the endless first sealing material 9 (O-ring) is accommodated is formed around the manifold M of the separator 7A, and the modules 300 and 300 are stacked. In the posture, both concave grooves 7Aa and 7Aa can form a space for accommodating a part of the seal material 9, and the seal material 9 is positioned and fixed in the space.

  In the illustrated example, a gap is formed between the stacked modules 300 and 300. However, when the stacking is performed, the sealing material 9 is crushed so that the separators 7A and 7A of the modules 300 and 300 can come into surface contact. It is like that.

  A desired number of modules 300,... Are stacked and stacked to form a fuel cell stack 1000.

  According to the illustrated fuel cell stack 1000, when removing the module 300 including the fuel cell in which power generation has failed, the stacking can be released, and then the sealing material 9 and the module 300 can be easily removed. By placing the new sealant 9 on both ends of the module 300 and then stacking it again, maintenance can be performed very easily. Moreover, the new fuel cell stack 1000 can be regenerated without degrading the sealing performance of the replacement module even after maintenance.

  FIG. 4 shows a part of the fuel cell stack in which the second sealing material 9A made of an elastic material surrounding the manifold M is arranged on the outer periphery of the first sealing material 9.

  The gas diffusion layer (GDL) constituting the fuel cell has elasticity, and is formed slightly thick in the cell stacking direction before stacking. When the stack is stacked, the gas diffusion layer is elastically deformed and compressed. As a result, a design is made such that the compressive force during stacking is applied to the membrane electrode assembly. Therefore, as shown in FIG. 5, when a single module 300 is formed by integrally connecting a plurality of fuel cells with gaskets, a thicker gas diffusion layer is added to the module before stacking. Since the number of cells to be configured is stacked, while the end of the module is fixed with a gasket, the central region of the module 300 swells outward (X direction), and exhibits a so-called drum shape. When the drum-shaped modules 300 and 300 whose center bulges outward and the periphery of the drum-shaped modules 300 and 300 are stacked, both modules 300 and 300 come into contact with each other on the center side, and manifolds M and M of the periphery are formed. A gap is formed in the region, and the fluid sealability around the manifold M cannot be secured.

  Therefore, as shown by a two-dot chain line in FIG. 5, an endless second sealing material 9A made of, for example, rubber and having a relatively large thickness is arranged around the manifold M and stacked, as shown in FIG. The sealing material 9A can completely close the space between the modules 300 and 300 to ensure the sealing performance around the manifold M.

  In the illustrated example, a structure is shown in which a first sealing material 9 made of an O-ring and a second sealing material 9A made of rubber are arranged on the outer periphery thereof, but the first sealing material 9 is made of rubber. In the case of a sealing material, only the first sealing material 9 may be used.

  FIG. 6 is a modified example of FIG. 3 and shows a module 400 in which the gasket 8B has a structure in which separators 7 and 7A having a three-layer structure are completely embedded. A desired number of modules 400,... Are stacked and stacked to form a fuel cell stack 2000.

  The fuel cell stack described above includes an end plate, a tension plate, and the like on the outermost side, and a compressive force is applied between the tension plates at both ends to form a fuel cell. A fuel cell system mounted on an electric vehicle or the like includes this fuel cell, various tanks for storing hydrogen gas and air, a blower for supplying these gases to the fuel cell, a radiator for cooling the fuel cell, a fuel The battery is generally composed of a battery that stores electric power generated by the battery, a drive motor that is driven by the electric power, and the like.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

It is the longitudinal cross-sectional view which showed one Embodiment of the module integrated with the gasket by which the some fuel cell was integrally molded. It is the longitudinal cross-sectional view which showed other embodiment of the module. FIG. 5 is a longitudinal sectional view showing still another embodiment of the module and a fuel cell stack formed by stacking the modules. It is the longitudinal cross-sectional view which showed other embodiment of the module. It is a figure explaining the subject at the time of laminating | stacking modules. FIG. 5 is a longitudinal sectional view showing still another embodiment of the module and a fuel cell stack formed by stacking the modules.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Membrane electrode assembly (MEA), 2 ... (cathode side) gas diffusion layer, 3 ... (anode side) gas diffusion layer, 4 ... Electrode body (MEGA), 5 ... (cathode side) porous body, 6 ... ( Anode side) porous body, 7 ... separator, 71, 72 ... metal plate, 73 ... intermediate layer for flow path formation, 7a ... gas flow path, 8, 8A, 8B ... gasket, 8a ... endless rib for sealing, 9 ... 1st sealing material (O-ring), 9A ... 2nd sealing material, 10, 20 ... Fuel cell, 100, 200, 300, 400 ... Module, 1000, 2000 ... Fuel cell stack, M ... Manifold

Claims (4)

A plurality of fuel cells comprising a membrane electrode assembly, an anode-side and cathode-side porous body that serves as a gas flow path sandwiching the membrane-electrode assembly, and a separator on either the anode-side or the cathode-side are stacked, A gasket formed integrally with the periphery of each laminated membrane electrode assembly and porous body is formed to form one module composed of a plurality of fuel cells,
A plurality of the modules are stacked to form a fuel cell stack ,
The fuel battery cell is formed with a plurality of manifolds for flowing at least one of fuel gas, oxidant gas, and cooling water,
Separators are arranged at both ends of the module,
A fuel cell in which an endless first sealing material surrounding the manifold is interposed between the separators of adjacent modules. Endless concave grooves are formed at the corresponding positions on the opposing surfaces of the separators of adjacent modules and around the manifolds. the endless space defined by the recessed groove, a part or all of the first sealing member is housed, a fuel cell according to claim 1. The fuel cell according to claim 1 or 2 , wherein a peripheral edge of the separator is also embedded in the gasket, and the gasket is continuous in one module. Between the end faces of each of opposite of the module adjacent and to the peripheral edge of the end surface, the second sealing material of endless having elasticity is Remodeling, according to any one of claims 1 to 3 Fuel cell.

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