JP2011070993A - Fuel cell and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell capable of achieving miniaturization of a cell of the fuel cell by omitting a gas passage layer while burr and cut pieces generated at a pre-processing stage are canceled without damaging a gas diffusion layer and lessening a size of the fuel cell where fuel cell cells are laminated, and to provide a method of manufacturing the same. <P>SOLUTION: In the method of manufacturing the fuel cell 200 wherein the cell of the fuel cell is formed with a membrane-electrode assembly 3, the gas diffusion layers 4A, 4B arranged on both side faces of the membrane-electrode assembly 3, and a separator 6 for holding two gas diffusion layers 4A, 4B and the cell of the fuel cells are laminated, a cell laminated body is formed by stacking the plurality of fuel cell cells, the cell laminated body is compressed (compression force Q) from a direction perpendicular to the cell stacking direction, and gas passage holes 8 extending in an in-plane direction are formed inside the gas diffusion layers 4A, 4B by means of this compressing. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel cell having a gas passage hole extending in an in-plane direction in a gas diffusion layer, and a method for manufacturing the fuel cell.

  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. An electrode body (MEGA: Membrane Electrode & Gas Diffusion Layer Assembly) is formed from the membrane electrode assembly and the anode-side and cathode-side gas diffusion layers (GDL) sandwiching the membrane-electrode assembly, and a fuel gas or an oxidant is formed on the electrode body A gas flow path layer made of a porous metal body for collecting gas and collecting electricity generated by an electrochemical reaction and a separator are arranged on both sides of the electrode body. In addition, the fuel cell in which the gas flow channel groove is formed in the separator is also a conventional one, and in this case, the metal porous body that becomes the gas flow channel layer is unnecessary. An actual fuel cell stack is formed by stacking radix fuel cells corresponding to required power and stacking, ie, compressing, fuel cells in the stacking direction.

  In the fuel cell described above, hydrogen gas or the like is provided as a fuel gas to the anode electrode, oxygen or air is provided as the oxidant gas to the cathode electrode, and each electrode has a unique gas flow path layer (or formed in a separator). The gas flows in the in-plane direction in the gas channel groove), and then the gas diffused in the gas diffusion layer is guided to the electrode catalyst layer to cause an electrochemical reaction.

  In general, the catalyst layer has a smaller planar area (smaller planar area) than the electrolyte membrane, and a polymer material reinforcing membrane is formed in the exposed region at the periphery of the catalyst layer where the electrolyte membrane is not covered with the catalyst layer. (Or a protective film) is provided, and a structure in which this reinforcing membrane is interposed between the gas diffusion layer and the electrolyte membrane is common. By interposing the reinforcing membrane between the gas diffusion layer and the electrolyte membrane in the peripheral region of the catalyst layer, the electrolyte membrane (membrane electrode assembly) having the catalyst layer and the gas diffusion layer are placed in a high temperature atmosphere of about 100 to 130 ° C., for example. Fluff protruding from the surface of the fibrous gas diffusion layer (or the diffusion layer base material constituting it) when thermocompression bonding with a compression force of about 1 to 3 MPa (thermocompression bonding conditions that do not affect the electrolyte membrane) Can be prevented from piercing the electrolyte membrane.

  On the other hand, a gas diffusion layer is disposed on both sides of the anode and cathode sides of the membrane electrode assembly, and a fuel cell comprising a gas channel layer made of a metal porous body on the anode side and cathode side and a separator sandwiched between the gas diffusion layers In a fuel cell in which cells are stacked and stacked, a fuel gas or an oxidant gas provided to a gas flow path layer via a separator flows through the gas flow path layer in the in-plane direction. Diffusion is provided to the diffusion layer, and is provided to the membrane electrode assembly via the gas diffusion layer.

  This separator has, for example, a three-layer structure in which a plate in which a flow path is formed between two plates made of titanium or stainless steel, or an intermediate layer made of a resin frame material. There is a type in which a large number of dimples and ribs defining a flow path are projected from one side of a plate to form a cooling water flow path (a separator having such a structure is also included in a three-layered separator). The separator having such a structure is a separator on either the anode side or the cathode side of the cell itself and at the same time the other separator on the anode side or the cathode side of an adjacent cell in the stacking posture. That is, the cell constituent member of the fuel cell having this three-layer structure separator includes one three-layer structure separator, a metal porous body (gas channel layer) on the anode side and the cathode side, and a membrane electrode assembly or electrode body. In a posture in which a plurality of fuel cells are stacked, an arbitrary fuel cell has anode-side and cathode-side separators at both ends thereof.

  By the way, when the demand for hybrid vehicles and electric vehicles expands, in order to realize further reduction in fuel consumption, weight reduction and size reduction of mounted fuel cells are one of the important development factors. In view of this, the fuel cell having the above-described configuration, that is, a gas flow path layer made of a metal porous body that allows gas to flow in the plane thereof, has a structure in which the gas diffusion layer and the membrane electrode assembly are sandwiched. In the fuel cell, for example, other constituent members have the expected effect on the gas flow path layer, that is, the function of diffusing the gas in the in-plane direction. The development of technology that can reduce the size of the body is eagerly desired.

  Here, a fuel cell in which a gas hollow channel is formed in the gas diffusion layer, the gas is circulated in the in-plane direction by the gas diffusion layer, and the gas circulated in the surface can be diffused to the membrane electrode assembly side. However, this is disclosed in Patent Document 1.

JP 2006-339089 A

  According to the fuel cell disclosed in Patent Document 1, the gas flow path layer made of a metal porous body or the like can be omitted by providing the gas diffusion layer capable of circulating the gas in the in-plane direction. The size of the battery cell (fuel cell) can be reduced. However, in this fuel cell, it is essential to perform pre-processing such as grooving or pressing directly on the gas diffusion layer. There are many problems to be solved such as the risk of being damaged and the problem of processing of burrs and cut pieces that may occur in the pre-processing, and it cannot be denied that this is far from a practical and effective improvement technique. Furthermore, since there is no change in stacking fuel cells and stacking them in this stacking direction to apply a compressive force to each fuel cell, fluff from the gas diffusion layer and the above-mentioned burrs are bonded to the membrane electrode. The problem of sticking into the body and possibly forming a gas cross-leakage path through the electrolyte membrane remains unresolved.

  The present invention has been made in view of the above problems, and eliminates the gas flow path layer while eliminating the burrs and cut pieces that may occur in the pre-processing stage without damaging the gas diffusion layer, and the fuel cell. It is an object of the present invention to provide a fuel cell capable of realizing a reduction in the size of the cell, and hence a reduction in the size of the fuel cell in which the fuel cells are stacked, and a method for manufacturing the fuel cell.

  In order to achieve the above object, a method of manufacturing a fuel cell according to the present invention includes a membrane electrode assembly, a gas diffusion layer disposed on both side surfaces of the membrane electrode assembly, and a separator sandwiching the two gas diffusion layers. And a fuel cell manufacturing method in which the fuel cell is formed by laminating a plurality of the fuel cell cells to form a cell stack, Compressing from the direction orthogonal to the cell stacking direction, and by this compression, gas flow path holes extending in the in-plane direction are formed in the gas diffusion layer.

  The fuel cell manufacturing method of the present invention is an improvement over the conventional method in which stacking is performed in the stacking direction of the stacked fuel cells, and the stacked fuel cells are fastened by the compressive force at the time of stacking. In addition, by executing the stacking direction, that is, the compression direction from the direction orthogonal to the cell stacking direction, a gas flow path hole extending in the in-plane direction is formed in the gas diffusion layer by the compression force from the lateral direction. Thus, the gas channel hole is used as a constituent element instead of the gas channel layer.

  In this manufacturing method, it is not completely excluded to apply a compressive force in the cell stacking direction, which is applied in the conventional manufacturing method. In other words, the compressive force from the direction perpendicular to the cell stacking direction can be relatively increased compared to the compressive force in the cell stacking direction, whereby the gas diffusion layer can be expanded from the direction orthogonal to the cell stacking direction. The gas channel hole is still formed by the compressive force. And even if the hole size of the gas flow path hole is reduced by the compression force in the cell stacking direction, both compression forces, so that the reduced hole size becomes the desired gas flow path hole size, It is sufficient that the deformation performance of the gas diffusion layer itself is adjusted. By applying a compressive force in two directions with the mutual compressive force adjusted to the stack of fuel cells, the fastening of the fuel cell stack and the formation of the gas flow path hole in the gas diffusion layer Both sides can be guaranteed.

  Here, as one embodiment of the gas diffusion layer used in the production method of the present invention, the first gas diffusion layer and the second gas diffusion layer are laminated, and these are connected at a plurality of connection points to Forming a gas diffusion layer and forming the gas flow path hole by deforming the first gas diffusion layer and the second gas diffusion layer between the adjacent connecting portions by the compression. it can.

  According to this embodiment, for example, two layered gas diffusion layers (first and second gas diffusion layers) are stacked and connected at a plurality of connection points. When the two are compressed from the side, the first and second gas diffusion layers between the adjacent connection points are deformed, for example, opposite to each other while the connection points maintain the connection structure. By the deformation, gas flow path holes having an elliptical shape, a circular shape, or a shape similar to them can be formed.

  Here, the gas diffusion layer can be of a general structure, that is, for example, a structure in which carbon fibers are knitted, a structure composed of this and a binder (including binder fibers), and two gas can be used. In the connection location where the diffusion layers are connected, the structure and structure of the connection location, such as the method of stitching the gas diffusion layers with a suture, the method of connecting with an adhesive, and the method of connecting with a combination of them, etc. Moreover, it can select suitably.

  According to the fuel cell manufacturing method described above, the expected action of the gas flow path layer, that is, the oxidant gas or fuel gas provided in the cell via the separator is circulated in the in-plane direction of the gas flow path layer. The gas channel hole formed in the gas diffusion layer can perform the function of causing the gas circulated in the in-plane direction in the gas diffusion layer directly in the gas diffusion layer to the membrane electrode. The bonded body can be distributed and provided. Therefore, it is possible to eliminate the gas flow path layer made of the metal porous body from the constituent members of the fuel cell, and to reduce the size of the fuel cell, and hence the size of the fuel cell stack in which the fuel cell stack is laminated. Can be realized. Further, the elimination of the gas flow path layer leads to a reduction in the cost required for manufacturing the fuel cell.

  In addition, in the fuel cell manufactured by the above-described fuel cell manufacturing method, no compressive force is applied in the cell stacking direction, or excessive compressive force is not applied, so that in the cell stacking direction as in the conventional manufacturing method. An excessive compressive force is applied, and the risk that fluff from the gas diffusion layer may penetrate the electrolyte membrane and form a gas cross-leakage path at that time can be suppressed or suppressed.

  The fuel cell according to the present invention includes a membrane electrode assembly, a gas diffusion layer disposed on both sides of the membrane electrode assembly, and a separator sandwiching the two gas diffusion layers. A fuel cell in which the fuel cells are stacked, and in the fuel cell, a cell stack in which a plurality of the fuel cells are stacked is compressed from a direction perpendicular to the cell stacking direction. The gas flow path hole formed in the gas diffusion layer and extending in the in-plane direction of the gas diffusion layer is provided.

  As one embodiment of this fuel cell, the gas diffusion layer is formed by laminating a first gas diffusion layer and a second gas diffusion layer, and these are connected at a plurality of connection points, Examples of the gas flow path hole include those formed by deforming the first gas diffusion layer and the second gas diffusion layer between the adjacent connecting portions during the compression.

  According to the fuel cell of the present invention described above, as already described regarding the fuel cell manufactured by the manufacturing method of the present invention, sufficient diffusion of oxidant gas and fuel gas in the in-plane direction of the gas diffusion layer is provided. The gas flow path layer made of a metal porous body can be abolished and the size can be reduced, and further, the fluff from the gas diffusion layer to the membrane electrode assembly and the resulting gas cross leak path Can be eliminated.

  As can be understood from the above description, according to the fuel cell of the present invention and the method for manufacturing the same, the surface of the gas diffusion layer is not directly cut or pressed, but the surface thereof is formed in the gas diffusion layer. A gas flow path formed of a metal porous body that forms a gas flow path hole extending in an inward direction, and thus ensures sufficient diffusion in the in-plane direction of the gas diffusion layer of the fuel gas or oxidant gas. A layer can be abolished, and further, an excessive compressive force in the cell stacking direction does not act on the cell stack. Therefore, while effectively solving the problem that fluff from the gas diffusion layer can penetrate the electrolyte membrane and form a gas cross-leakage path, it is possible to reduce both the size of the fuel cell and the manufacturing cost. Can be realized.

It is a figure explaining the manufacturing method of the fuel battery | cell of this invention, Comprising: The cell laminated body formed by laminating | stacking a fuel battery cell is formed, and it is the longitudinal cross-sectional view which showed the state before giving compressive force to this. FIG. 2 is a longitudinal sectional view showing the fuel cell of the present invention manufactured by applying a compressive force to the cell stack from a direction orthogonal to the stacking direction of the fuel cells, following FIG. 1. In the fuel cell shown in FIG. 2, it is the cross-sectional view cut | disconnected in the cross section which passes along a gas flow path hole.

Embodiments of a fuel cell and a method for manufacturing the same according to the present invention will be described below with reference to the drawings.
1 and 2 are diagrams for explaining a method for manufacturing a fuel cell according to the present invention, and FIG. 2 further shows a fuel cell according to the present invention manufactured by this manufacturing method.

  First, a cell laminate is formed by laminating a predetermined number of fuel cells. Each fuel battery cell 10 constituting the cell stack 100 includes a membrane electrode assembly 3 formed of an electrolyte membrane 1 and cathode and anode catalyst layers 2A and 2B. The membrane electrode assembly 3 is formed on the cathode and anode sides. The gas diffusion layers 4A and 4B are sandwiched to form an electrode body 5, a separator 6 having a three-layer structure is disposed on the cathode side of the electrode body 5, and a resin material gasket 7 is formed on the periphery of the electrode body 5. The whole is roughly structured. As shown in the drawing, in a posture in which a plurality of fuel cells 10 are stacked and stacked, the electrode body 5 is sandwiched between its own separator 6 and the separator 6 of the adjacent fuel cell 10 in the stacking posture. It becomes a structure. That is, in this structure, the oxidant gas is supplied to the electrode body 5 via the cathode side plate 61 of its own separator 6, and the anode side of the separator 6 of the adjacent fuel cell 10 in the stacked posture. A fuel gas is supplied to the electrode body 5 through the plate 62.

  Here, the area of the catalyst layers 2A and 2B is smaller than that of the electrolyte membrane 1, and therefore the catalyst layers 2A and 2B do not exist at the periphery of the catalyst layers 2A and 2B on both sides of the electrolyte membrane 1. An exposed region 1 ′ is formed.

  It is preferable that a reinforcing film (not shown) is disposed in the exposed region 1 ′. For example, the exposed region is exposed from the catalyst layers 2A and 2B in a posture in which a part of the reinforcing film is wrapped on the catalyst layers 2A and 2B. A form in which the reinforcing film is arranged over 1 ′ can be mentioned. By providing this reinforcing film, it is possible to completely protect the fluff protruding from the gas diffusion layers 4A and 4B from being stuck into the electrolyte membrane 1.

  Here, the electrolyte membrane 1 constituting the membrane electrode assembly 3 includes, 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, It is formed from a non-fluorine polymer such as sulfonated phenylene sulfide.

  The catalyst layers 2A and 2B are formed by mixing a conductive carrier (particulate carbon carrier, etc.) carrying a catalyst, an electrolyte, and a dispersion solvent (organic solvent) to produce a catalyst solution (catalyst ink). Then, the catalyst layer is formed by stretching this in a layer shape with a coating blade, for example, on a substrate such as the electrolyte membrane 1 or the gas diffusion layers 4A and 4B, and drying in a warm air drying furnace or the like. The 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.

  Each of the gas diffusion layers 4A and 4B includes two layered first gas diffusion layers 4Aa and 4Ba and a second gas diffusion layer 4Ab and 4Bb, which are stacked at a plurality of connecting portions 4C,. It is configured to be connected.

  The first gas diffusion layers 4Aa and 4Ba and the second gas diffusion layers 4Ab and 4Bb are not particularly limited as long as they have low electrical resistance and can collect current. Examples of the conductive inorganic substance include calcined products from polyacrylonitrile, calcined products from pitch, carbon materials such as graphite and expanded graphite, nanocarbon materials thereof, stainless steel, and the like. , Molybdenum, titanium and the like. Further, the form of the conductive inorganic substance is not particularly limited, and for example, it is used in the form of fibers or particles. From the viewpoint of gas permeability, it is an inorganic conductive fiber, and carbon fiber is particularly preferable. 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 a plain weave or a plain weave, and examples of the nonwoven fabric include a papermaking method and a water jet punch 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. In addition, the first gas diffusion layers 4Aa and 4Ba and the second gas diffusion layers 4Ab and 4Bb may be formed by integrating inorganic conductive fibers with a binder. In addition, perfluorocarbon sulfonic acid polymers such as Nafion, aromatic engineering plastic resins introduced with ion conductive groups such as sulfonic acid groups, and cationic conductive binders made of styrene thermoplastic elastomers can be used.

  The connecting portions 4C for connecting the first gas diffusion layers 4Aa and 4Ba and the second gas diffusion layers 4Ab and 4Bb described above are connected by, for example, a stitching method using a suture thread or a bonding method. Can be formed.

  A separator 6 having a three-layer structure is further laminated on the gas diffusion layer 4A on the cathode side. In the separator 6, a metal cathode side plate 61 and an anode side plate 62 made of stainless steel or titanium and an intermediate plate 63 (intermediate plate) interposed therebetween are integrated by brazing or the like.

  The intermediate plate 63 constituting the separator 6 shown in the figure has an introduction path (not shown) for supplying an oxidant gas to the gas diffusion layer 4A on the cathode side of the fuel battery cell which is a constituent element, and a stack of cells. In the posture, an introduction path (not shown) for supplying fuel gas to the gas diffusion layer 4B on the anode side of the adjacent fuel battery cell is formed. Furthermore, a cooling channel (not shown) through which a cooling medium such as cooling water flows is formed.

  As shown in FIG. 1, the respective constituent elements constituting the predetermined number of fuel cells 10 are sequentially laminated, and a gasket 7 is formed around these peripheral edges to be integrated temporarily. The outline of the molding method of the gasket 7 is that a cell laminate before molding the gasket 7 is accommodated in a molding die (not shown), and a resin is placed in the gasket cavity on the side of the membrane electrode assembly of each fuel cell. Is performed by a method such as injection (injection molding). Here, as the material of the gasket, methanol-resistant epoxy resin, epoxy-modified silicone resin, silicone resin, fluorine resin, urethane RTV rubber, butyl rubber resin, silicone RTV rubber, EPDM resin, etc. are used. it can.

  As is clear from FIG. 1, the gas flow path layer made of expanded metal, metal foam sintered body, or the like is not included as a component of each fuel cell 10 constituting the cell stack 100.

  Next, as shown in FIG. 2, the fuel cell 200 is manufactured by stacking the cell stack 100 with a compressive force Q from a direction orthogonal to the cell stacking direction (from the lateral direction in the figure).

  The first gas diffusion layer 4Aa, the second gas diffusion layer 4Ab, the first gas diffusion layer 4Ba, and the second gas diffusion layer constituting the gas diffusion layers 4A, 4B by the compressive force Q from the lateral direction. 4Bb is displaced to the opposite side with respect to the other, and as these are displaced, in the gas diffusion layers 4A and 4B, as shown in FIG. 3, for example, a gas supply manifold for fuel gas or oxidant gas A plurality of gas flow path holes 8, 8 leading from the M to the gas exhaust manifold M are formed.

  That is, when the compressive force Q is applied to the cell stack 100, the first and second gas diffusion layers 4Aa, 4Aa between the adjacent connecting portions 4C, 4C while the connecting portion 4C maintains the connecting structure. 4Ba, 4Ab, and 4Bb are deformed, for example, to the opposite sides, and due to this deformation, the gas flow path holes 8 and 8 having a flow path cross section that is elliptical, circular, or a shape similar to them as shown in FIG. To form.

  This gas flow path hole 8 has the same effect as a gas flow path layer made of a metal porous body in a fuel cell having a conventional structure, and the gas provided from the gas supply manifold to the gas diffusion layers 4A and 4B. Is diffused and provided in the gas diffusion layers 4A and 4B in the in-plane direction through the gas passage hole 8, and the gas provided in the in-plane direction is joined to the membrane electrode via the gas diffusion layers 4Aa and 4Ba. Provided to body 3.

  As described above, in the manufacturing method of the present invention and the fuel cell 200 manufactured by this manufacturing method, the gas diffusion layers 4A and 4B as the constituent members are respectively connected by the two gas diffusion layers via the connecting portion 4C. The two gas diffusion layers are connected to form the gas flow path hole 8, and it is necessary to directly cut or press the gas diffusion layer as in the conventional manufacturing method. Therefore, it is not necessary to shorten the time required for this pretreatment, and to handle burrs and cut pieces that may occur in this pretreatment.

  Further, a gas flow path hole (which diffuses and provides gas in the in-plane direction) can be formed in the gas diffusion layer by the compressive force Q from the lateral direction, so that the gas flow path layer is not required. As a result, it is possible to simultaneously reduce both the size of the fuel cell and the size of the fuel cell and the manufacturing cost.

  Furthermore, since an excessive compressive force does not act on the cell stacking method, the fluff from the gas diffusion layer pierces the membrane electrode assembly by this excessive compressive force, penetrates the electrolyte membrane, and crosses the gas cross leak path. The problem that it can be formed cannot occur.

  As shown in FIG. 2, in addition to applying a compressive force Q to the cell stack 100 from a direction orthogonal to the cell stacking direction, a compressive force P smaller than the compressive force Q is applied in the cell stacking direction. The method of manufacturing the fuel cell stack may be applied to the above.

  Since the compressive force P is smaller than the compressive force Q, stacking is performed in the vertical direction and the horizontal direction while suppressing the excessive compressive force in the cell stacking direction from acting on each fuel cell 10. It is possible to further reduce the interfacial resistance between the cell constituent members while suppressing the formation of a cross leak path penetrating the membrane.

  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.

  DESCRIPTION OF SYMBOLS 1 ... Electrolyte membrane, 1 '... Exposed area | region of electrolyte membrane, 2A ... Cathode side catalyst layer, 2B ... Anode side catalyst layer, 3 ... Membrane electrode assembly, 4A ... Cathode side gas diffusion layer, 4Aa ... 1st Gas diffusion layer, 4Ab ... second gas diffusion layer, 4B ... gas diffusion layer on the anode side, 4Ba ... first gas diffusion layer, 4Bb ... second gas diffusion layer, 4C ... connection portion, 5 ... electrode body , 6 ... Separator, 61 ... Cathode side plate, 62 ... Anode side plate, 63 ... Intermediate layer (intermediate plate), 7 ... Gasket, 8 ... Gas channel hole, 100 ... Cell stack, 200 ... Fuel cell, Q ... Compressive force (direction perpendicular to cell stacking direction), P ... Compressive force (cell stacking direction)

Claims (4)

A fuel cell is formed from a membrane electrode assembly, a gas diffusion layer disposed on both sides of the membrane electrode assembly, and a separator sandwiching the two gas diffusion layers, and the fuel cell is laminated. A fuel cell manufacturing method comprising:
A plurality of the fuel battery cells are stacked to form a cell stack, and the cell stack is compressed from a direction orthogonal to the cell stacking direction, and this compression extends in the in-plane direction into the gas diffusion layer. A method of manufacturing a fuel cell, wherein a gas flow path hole is formed. The gas diffusion layer is configured by laminating a first gas diffusion layer and a second gas diffusion layer, and connecting them at a plurality of connection points.
2. The fuel cell according to claim 1, wherein the compression causes the first gas diffusion layer and the second gas diffusion layer to deform to form the gas flow path hole between the adjacent connecting portions. Manufacturing method. A fuel cell is formed from a membrane electrode assembly, a gas diffusion layer disposed on both sides of the membrane electrode assembly, and a separator sandwiching the two gas diffusion layers, and the fuel cell is laminated. A fuel cell comprising:
In the fuel cell, a cell laminate formed by laminating a plurality of the fuel cells is compressed from a direction orthogonal to the cell stacking direction, and is formed in the gas diffusion layer by this compression. A fuel cell having a gas passage hole extending in a direction. The gas diffusion layer is formed by laminating a first gas diffusion layer and a second gas diffusion layer, and these are connected at a plurality of connection points,
The gas flow path hole is formed by deforming the first gas diffusion layer and the second gas diffusion layer between the adjacent connecting portions during the compression. The fuel cell as described.

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