JP6174524B2 - Fuel cell - Google Patents

Description

  The present invention relates to a fuel cell including a framed electrolyte membrane / electrode structure in which a resin frame member is provided around an outer periphery of an electrolyte membrane / electrode structure in which electrodes are respectively disposed on both sides of a solid polymer electrolyte membrane. .

  In general, a polymer electrolyte fuel cell employs a polymer electrolyte membrane made of a polymer ion exchange membrane. This fuel cell includes an electrolyte membrane / electrode structure (MEA) in which an anode electrode is disposed on one side of a solid polymer electrolyte membrane and a cathode electrode is disposed on the other side of the solid polymer electrolyte membrane. . The electrolyte membrane / electrode structure is sandwiched between separators (bipolar plates) to constitute a fuel cell. A predetermined number of the fuel cells are stacked, for example, mounted on a fuel cell electric vehicle as an in-vehicle fuel cell stack.

  In a fuel cell, a configuration in which a seal member is integrated with an outer periphery of an electrolyte membrane / electrode structure may be employed. This is because it becomes possible to suppress leakage of fuel gas and oxidant gas, or cross-leakage of these.

  For example, in the fuel cell disclosed in Patent Document 1, seal-integrated assemblies and separators are alternately stacked. The seal-integrated assembly includes an MEA (membrane electrode assembly), an anode-side porous body and a cathode-side porous body disposed on both sides of the MEA, and a gasket.

  The anode-side porous body and the cathode-side porous body are formed from a metal porous body or a carbon porous body, and function as flow paths through which fuel gas and oxidant gas are circulated. The gasket is a frame-like member and is disposed around the MEA and has convex lip portions on both sides of the anode side and the cathode side. The lip portion is in close contact with the separator surface and forms a seal line with the separator.

JP 2009-129650 A

  By the way, in said patent document 1, in order to form a reaction gas flow path in a separator, the said separator is comprised with three plates. For this reason, there is a problem that the structure of the separator becomes complicated and the number of plates increases, which is not economical.

  The present invention solves this type of problem, and an object of the present invention is to provide a fuel cell that can easily and satisfactorily constitute a separator and can be manufactured economically.

  The fuel cell according to the present invention has an electrolyte membrane / electrode structure in which electrodes are respectively disposed on both sides of a solid polymer electrolyte membrane, and a resin frame member circulates around the outer periphery of the electrolyte membrane / electrode structure. A framed electrolyte membrane / electrode structure is provided. The framed electrolyte membrane / electrode structure is sandwiched between a pair of separators.

The electrode is provided with a porous gas diffusion layer in which a reaction gas flow path for allowing a reaction gas to flow along the separator surface direction is formed. The resin frame member includes a gas introduction part for supplying a reaction gas to the end surface on the reaction gas flow path inlet side of the porous gas diffusion layer, and the reaction gas from the reaction gas flow path outlet end surface of the porous gas diffusion layer And a gas lead-out part for discharging the gas. The resin frame member is laminated in the order of the first resin sheet member, the second resin sheet member, and the third resin sheet member, and between the first resin sheet member and the second resin sheet member, A fuel gas introduction part that is a gas introduction part and a fuel gas lead part that is the gas lead-out part are formed, and the gas introduction part is provided between the second resin sheet member and the third resin sheet member. And an oxidant gas lead-out part which is the gas lead-out part.

  In this fuel cell, the resin frame member is preferably provided with a reaction gas inlet communication hole for allowing the reaction gas to flow in the stacking direction intersecting the separator surface direction. In that case, the gas introduction part communicates with the reaction gas inlet communication hole, extends along one side of the resin frame member, and the reaction gas channel inlet of the connection channel and the porous gas diffusion layer. It is preferable to have a plurality of passages connected to the side end surface.

  Further, in this fuel cell, the resin frame member is preferably provided with a reaction gas outlet communication hole through which the reaction gas flows in the stacking direction intersecting the separator surface direction. In that case, the gas lead-out part communicates with the reaction gas outlet communication hole and extends along one side of the resin frame member, and the reaction gas channel outlet of the connection channel and the porous gas diffusion layer. It is preferable to have a plurality of passages connected to the side end surface.

  In this fuel cell, it is preferable that at least one separator adjacent to the framed electrolyte membrane / electrode structure is formed in a flat plate shape with a flat separator surface.

  Furthermore, in this fuel cell, it is preferable that a seal member is provided on the outer peripheral edge of the separator, and the seal member and the resin frame member are welded together.

  According to the present invention, the porous gas diffusion layer constituting the electrode constitutes a reaction gas flow path for allowing the reaction gas to flow along the inside in the separator surface direction. The resin frame member is supplied with a reaction gas from a reaction gas channel outlet side end surface of the porous gas diffusion layer and a gas introduction part for supplying a reaction gas to the reaction gas channel inlet side end surface of the porous gas diffusion layer. And a gas lead-out portion for discharging.

  For this reason, the separator does not require processing of the flow path system including the reaction gas flow path, and the manufacturing work of the separator is simplified at a stroke. Thereby, a separator can be manufactured easily and satisfactorily, the manufacturing cost of the entire fuel cell is reduced, and the fuel cell can be manufactured economically.

1 is an exploded perspective view of a fuel cell according to a first embodiment of the present invention. It is the II-II sectional view taken on the line of the said fuel cell in FIG. It is a principal part cross-section perspective explanatory drawing of the electrolyte membrane and electrode structure with a frame which comprises the said fuel cell. It is the IV-IV sectional view taken on the line of the said fuel cell in FIG. It is front explanatory drawing of the said electrolyte membrane and electrode structure with a frame. It is principal part cross-sectional explanatory drawing of the fuel cell which concerns on the 2nd Embodiment of this invention.

  As shown in FIG. 1, a plurality of fuel cells 10 according to the first embodiment of the present invention are stacked in the arrow A direction (horizontal direction) or the arrow C direction (gravity direction) to form a fuel cell stack. The fuel cell stack is mounted on a fuel cell vehicle (fuel cell electric vehicle) (not shown) as, for example, an in-vehicle fuel cell stack.

  As shown in FIGS. 1 and 2, the fuel cell 10 sandwiches a framed electrolyte membrane / electrode structure (framed MEA) 12 between a cathode side separator 14 and an anode side separator 16. The cathode side separator 14 and the anode side separator 16 have a horizontally long (or vertically long) rectangular shape.

  The cathode-side separator 14 and the anode-side separator 16 are constituted by, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a thin plate-like metal plate whose surface is subjected to anticorrosion treatment. The cathode side separator 14 and the anode side separator 16 may be constituted by a carbon separator.

  As shown in FIG. 1, an oxidant gas inlet communication hole 18 a and a fuel gas outlet communication hole 20 b are provided vertically at one end edge of the fuel cell 10 in the long side direction (arrow B direction). The oxidant gas inlet communication holes 18a communicate with each other in the direction of arrow A to supply an oxidant gas, for example, an oxygen-containing gas. The fuel gas outlet communication holes 20b communicate with each other in the direction of arrow A, and discharge fuel gas, for example, hydrogen-containing gas.

  A fuel gas inlet communication hole 20a and an oxidant gas outlet communication hole 18b are provided vertically at the other end edge of the fuel cell 10 in the long side direction (arrow B direction). The fuel gas inlet communication holes 20a communicate with each other in the direction of arrow A to supply fuel gas. The oxidant gas outlet communication holes 18b communicate with each other in the direction of arrow A to discharge the oxidant gas.

  The cooling medium is supplied to one end edge (upper edge) in the short side direction (arrow C direction) of the fuel cell 10 so as to communicate with each other in the arrow A direction. ) Cooling medium inlet communication hole 22a. In order to discharge the cooling medium at the other end edge (lower edge) in the short side direction (arrow C direction) of the fuel cell 10, for example, three (or more) cooling medium outlet connections are possible. A hole 22b is provided.

  As shown in FIG. 2, the cathode-side separator 14 is formed in a planar shape with a flat separator surface, and the anode-side separator 16 is formed into a corrugated cross-section by pressing into a wave shape. The concavo-convex shape portion is provided on the separator surface of the anode-side separator 16 by alternately providing concave portions and convex portions along the arrow B direction, so that the cooling medium flow path extending in the arrow C direction on the surface 16b on the back surface side. 24 is formed (see FIG. 1). The cathode separator 14 may be provided with a convex portion that comes into contact with a first porous gas diffusion layer 36b described later. The convex portion has a minute change in the height direction and maintains a substantially planar shape as the separator surface.

  The cooling medium flow path 24 is constituted by a plurality of flow path grooves extending in the direction of arrow C. The upper (inlet) side communicates with the cooling medium inlet communication hole 22a, while the lower (outlet) side communicates with the cooling medium outlet communication hole. It communicates with 22b. The cooling medium flow path 24 is formed by overlapping the uneven surface 16b of the anode-side separator 16 and the planar surface 14b that is the back surface of the cathode-side separator 14 (see FIG. 2).

  As shown in FIGS. 1 and 2, a first seal member 26 is integrally formed around the outer peripheral edge of the surfaces 14 a and 14 b of the cathode separator 14. A second seal member 28 is integrally formed around the outer peripheral edges of the surfaces 16 a and 16 b of the anode separator 16.

  As the first seal member 26 and the second seal member 28, for example, EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber or the like, cushion material Alternatively, a sealing material having elasticity such as a packing material is used.

  As shown in FIGS. 1 to 3, the framed electrolyte membrane / electrode structure 12 includes an electrolyte membrane / electrode structure (MEA) 30 and a resin provided around the outer periphery of the electrolyte membrane / electrode structure 30. And a frame member 32.

  As shown in FIG. 2, the electrolyte membrane / electrode structure 30 includes, for example, a solid polymer electrolyte membrane (cation exchange membrane) 34 in which a perfluorosulfonic acid thin film is impregnated with water. The solid polymer electrolyte membrane 34 is sandwiched between a cathode electrode 36 and an anode electrode 38.

  The cathode electrode 36 constitutes a so-called step MEA having a planar dimension smaller than that of the anode electrode 38 and the solid polymer electrolyte membrane 34. The cathode electrode 36, the anode electrode 38, and the solid polymer electrolyte membrane 34 may be set to the same planar dimension. Further, the anode electrode 38 may have a planar dimension smaller than that of the cathode electrode 36 and the solid polymer electrolyte membrane 34.

  The cathode electrode 36 has a first electrode catalyst layer 36a joined to one surface 34a of the solid polymer electrolyte membrane 34, and a first porous gas diffusion layer 36b laminated on the first electrode catalyst layer 36a. . The anode electrode 38 has a second electrode catalyst layer 38a joined to the other surface 34b of the solid polymer electrolyte membrane 34, and a second porous gas diffusion layer 38b laminated on the second electrode catalyst layer 38a. .

  The first electrode catalyst layer 36a and the second electrode catalyst layer 38a are formed by, for example, printing, applying or transferring catalyst particles in which platinum particles are supported on carbon black on both surfaces 34a and 34b of the solid polymer electrolyte membrane 34. Composed.

  The first porous gas diffusion layer 36b and the second porous gas diffusion layer 38b are formed of, for example, a carbon porous body. The first porous gas diffusion layer 36b and the second porous gas diffusion layer 38b may be formed of a porous metal material such as porous titanium. The planar dimension of the second porous gas diffusion layer 38b is set to be larger than the planar dimension of the first porous gas diffusion layer 36b. Inside the second porous gas diffusion layer 38b, a fuel gas flow path 40 is formed through which fuel gas flows along the separator surface direction. Inside the first porous gas diffusion layer 36b, an oxidant gas flow path 42 is formed for flowing an oxidant gas along the separator surface direction. The fuel gas flow path 40 and the oxidant gas flow path 42 are configured to have opposite flow directions.

  As shown in FIGS. 1 to 3, the electrolyte membrane / electrode structure 30 is located outside the terminal portion of the cathode electrode 36, and the resin frame member 32 is integrated with the outer peripheral edge 34 ae of the solid polymer electrolyte membrane 34. It becomes. The resin frame member 32 is laminated in the order of the first resin sheet member 32a, the second resin sheet member 32b, and the third resin sheet member 32c. Examples of the resin material include PPS (polyphenylene sulfide), PPA (polyphthalamide), PEN (polyethylene naphthalate), PES (polyethersulfone), LCP (liquid crystal polymer), PVDF (polyvinylidene fluoride), silicone. It is composed of rubber, fluororubber, EPDM (ethylene propylene rubber), m-PPE (modified polyphenylene ether resin) or the like.

  As shown in FIG. 1, the resin frame member 32 includes an oxidant gas inlet communication hole 18a, a fuel gas inlet communication hole 20a, a cooling medium inlet communication hole 22a, an oxidant gas outlet communication hole 18b, and a fuel gas outlet communication hole 20b. The cooling medium outlet communication hole 22b is formed to penetrate therethrough. As shown in FIGS. 2 and 3, the first resin sheet member 32a and the third resin sheet member 32c are formed by bending a frame-shaped flat plate corresponding to the reaction gas flow path system, while the second resin sheet member 32b is constituted by a frame-shaped flat sheet.

  The first resin sheet member 32a, the second resin sheet member 32b, and the third resin sheet member 32c are integrated by bonding the contact surfaces to each other. As shown in FIG. 2, the inner peripheral edge of the second resin sheet member 32 b is bonded to the outer peripheral edge 34 ae of the solid polymer electrolyte membrane 34 via an adhesive 44.

  The first resin sheet member 32a has a flat portion 32af bonded to the second resin sheet member 32b, and protrudes from the flat portion 32af in the thickness direction, and the convex portion 32ap is integrally formed. Between the convex portion 32ap and the second resin sheet member 32b, a space portion constituting the flow path system is formed as will be described later.

  The first resin sheet member 32a is bonded, for example, with the inner peripheral edge (the inner peripheral edge of the convex portion 32ap) overlapping the outer peripheral edge of the second porous gas diffusion layer 38b constituting the anode electrode 38. As shown in FIG. 1, the first resin sheet member 32a protrudes around the oxidant gas inlet communication hole 18a, the oxidant gas outlet communication hole 18b, the cooling medium inlet communication hole 22a, and the cooling medium outlet communication hole 22b. It has the shape part 32ap.

  As shown in FIGS. 1, 3 and 4, in the first resin sheet member 32 a, the end surface of the second porous gas diffusion layer 38 b (from the fuel gas channel inlet side) is formed from the fuel gas inlet communication hole 20 a by the convex portion 32 ap. A fuel gas introduction part 46a for supplying fuel gas to the end face 38be1 is formed. The fuel gas introduction part 46a communicates with the fuel gas inlet communication hole 20a along one side of the resin frame member 32 (one short side where the fuel gas inlet communication hole 20a and the oxidant gas outlet communication hole 18b are provided). An extended fuel gas connection channel 48a is provided.

  A plurality of concave portions (planar portions 32af) 32ar are provided adjacent to the fuel gas connection channel 48a at predetermined intervals in the arrow C direction. Between the concave portions 32ar, a plurality of fuel gas supply passages 50a are formed which are continuous with the fuel gas connection channel 48a and the end face 38be1 of the second porous gas diffusion layer 38b.

  As shown in FIG. 1, in the first resin sheet member 32a, the fuel gas flows from the end surface (end surface on the fuel gas flow path outlet side) 38be2 of the second porous gas diffusion layer 38b to the fuel gas outlet communication hole 20b by the convex portion 32ap. A fuel gas lead-out portion 46b for discharging the gas is formed. The fuel gas outlet 46b communicates with the fuel gas outlet communication hole 20b along one side of the resin frame member 32 (the other short side where the oxidant gas inlet communication hole 18a and the fuel gas outlet communication hole 20b are provided). An extended fuel gas connection channel 48b is provided.

  A plurality of concave portions (planar portions 32af) 32ar are provided adjacent to the fuel gas connection channel 48b at predetermined intervals in the arrow C direction. Between the concave portions 32ar, a plurality of fuel gas discharge passages 50b are formed which are continuous with the fuel gas connection channel 48b and the end face 38be2 of the second porous gas diffusion layer 38b.

  As shown in FIGS. 2 and 3, the third resin sheet member 32 c has a flat portion 32 cf bonded to the second resin sheet member 32 b, and protrudes in the thickness direction from the flat portion 32 cf so as to have a convex portion 32 cp. Are integrally molded. Between the convex portion 32cp and the second resin sheet member 32b, a space portion constituting the flow path system is formed as will be described later.

  As shown in FIG. 2, the third resin sheet member 32 c has an inner peripheral edge portion (an inner peripheral edge portion of the convex portion 32 cp) overlapping an outer peripheral edge portion of the first porous gas diffusion layer 36 b constituting the cathode electrode 36. For example, it is adhered. As shown in FIG. 5, the third resin sheet member 32c has a convex portion that circulates around the fuel gas inlet communication hole 20a, the fuel gas outlet communication hole 20b, the cooling medium inlet communication hole 22a, and the cooling medium outlet communication hole 22b. 32 cp.

  As shown in FIG. 5, in the third resin sheet member 32c, the convex portion 32cp leads from the oxidant gas inlet communication hole 18a to the end surface (oxidant gas flow channel inlet side end surface) 36be1 of the first porous gas diffusion layer 36b. An oxidant gas introduction part 52a for supplying the oxidant gas is formed. The oxidant gas introduction part 52a communicates with the oxidant gas inlet communication hole 18a and is on one side of the resin frame member 32 (the other short side where the oxidant gas inlet communication hole 18a and the fuel gas outlet communication hole 20b are provided). It has an oxidant gas connection channel 54a extending along.

  A plurality of concave portions (planar portions 32cf) 32cr are provided adjacent to the oxidant gas connection channel 54a at predetermined intervals in the direction of arrow C. Between the concave portions 32cr, a plurality of oxidant gas supply passages 56a are formed which are continuous with the oxidant gas connection channel 54a and the end surface 36be1 of the first porous gas diffusion layer 36b.

  In the third resin sheet member 32c, the oxidant gas that discharges the oxidant gas from the end surface (oxidant gas outlet side end surface) 36be2 of the first porous gas diffusion layer 36b to the oxidant gas outlet communication hole 18b by the convex portion 32cp. A lead-out part 52b is formed. The oxidant gas outlet 52b communicates with the oxidant gas outlet communication hole 18b and is on one side of the resin frame member 32 (one short side where the fuel gas inlet communication hole 20a and the oxidant gas outlet communication hole 18b are provided). It has an oxidant gas connection channel 54b extending along.

  A plurality of concave portions (planar portions 32cf) 32cr are provided adjacent to the oxidant gas connection channel 54b at predetermined intervals in the arrow C direction. A plurality of oxidant gas discharge passages 56b connected to the oxidant gas connection channel 54b and the end surface 36be2 of the first porous gas diffusion layer 36b are formed between the concave portions 32cr (see FIGS. 4 and 5). .

  As shown in FIG. 2, the second seal member 28 provided on the anode separator 16 and the first resin sheet member 32a constituting the resin frame member 32 are welded by the weld layer 58a over the entire circumference. . The welding layer 58a seals between the anode side separator 16 and the first resin sheet member 32a. The first seal member 26 provided on the cathode side separator 14 and the third resin sheet member 32c constituting the resin frame member 32 are welded by the weld layer 58b over the entire circumference. The welding layer 58b seals between the cathode separator 14 and the third resin sheet member 32c. The welding layers 58a and 58b can be formed by various heating devices such as a laser heating device and an ultrasonic wave in addition to the electric heater.

  The operation of the fuel cell 10 configured as described above will be described below.

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 18a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 20a. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the three cooling medium inlet communication holes 22a.

  As shown in FIG. 5, the oxidant gas is supplied from the oxidant gas inlet communication hole 18a to the oxidant gas introduction part 52a formed between the second resin sheet member 32b and the third resin sheet member 32c. . The oxidant gas flows in the direction of the arrow C along the oxidant gas connection channel 54a constituting the oxidant gas introduction part 52a, and supplies a plurality of oxidant gases communicating with the oxidant gas connection channel 54a. The flow is diverted to the passage 56a and flows in the direction of arrow B.

  Therefore, the oxidant gas is supplied to the oxidant gas flow path 42 from the end face 36be1 of the first porous gas diffusion layer 36b along each oxidant gas supply passage 56a. The oxidant gas moves in the direction of arrow B (horizontal direction) along the oxidant gas flow path 42 in the first porous gas diffusion layer 36b, and reaches the first electrode catalyst layer 36a of the electrolyte membrane / electrode structure 30. Supplied.

  On the other hand, as shown in FIGS. 1 to 3, the fuel gas is supplied from the fuel gas inlet communication hole 20a to the fuel gas introduction part 46a formed between the second resin sheet member 32b and the first resin sheet member 32a. Is done. The fuel gas circulates in the direction of arrow C along the fuel gas connection channel 48a constituting the fuel gas introduction part 46a, and is divided into a plurality of fuel gas supply channels 50a communicating with the fuel gas connection channel 48a. In the direction of arrow B.

  Therefore, the fuel gas is supplied from the end face 38be1 of the second porous gas diffusion layer 38b to the fuel gas flow path 40 along each fuel gas supply passage 50a. The fuel gas moves in the direction of arrow B (horizontal direction) along the fuel gas flow path 40 in the second porous gas diffusion layer 38b, and is supplied to the second electrode catalyst layer 38a of the electrolyte membrane / electrode structure 30. The

  As a result, as shown in FIG. 2, in the electrolyte membrane / electrode structure 30, the oxidizing gas supplied to the first electrode catalyst layer 36 a of the cathode electrode 36 and the second electrode catalyst layer 38 a of the anode electrode 38 are supplied. The generated fuel gas is consumed by an electrochemical reaction to generate power.

  Next, as shown in FIGS. 2 to 5, the oxidant gas consumed by being supplied to the first electrode catalyst layer 36a of the electrolyte membrane / electrode structure 30 is supplied from the end face 36be2 of the first porous gas diffusion layer 36b. It is discharged to the oxidant gas outlet 52b. The oxidant gas flows in the direction of arrow B along the plurality of oxidant gas discharge passages 56b constituting the oxidant gas outlet 52b, and then joins the oxidant gas connection flow path 54b. The oxidant gas flows in the direction of arrow C and is discharged from the oxidant gas connection channel 54b to the oxidant gas outlet communication hole 18b.

  The fuel gas consumed by being supplied to the second electrode catalyst layer 38a of the electrolyte membrane / electrode structure 30 is discharged from the end 38ae2 of the second porous gas diffusion layer 38b to the fuel gas outlet 46b. The fuel gas flows in the direction of arrow B along the plurality of fuel gas discharge passages 50b constituting the fuel gas outlet 46b, and then merges with the fuel gas connection channel 48b. The fuel gas flows in the direction of arrow C and is discharged from the fuel gas connection channel 48b to the fuel gas outlet communication hole 20b.

  Furthermore, the cooling medium supplied to the three upper cooling medium inlet communication holes 22 a is between the cathode separator 14 constituting one fuel cell 10 and the anode separator 16 constituting the other fuel cell 10. Is introduced into the cooling medium flow path 24 formed in the above.

  The cooling medium supplied to the cooling medium flow path 24 from each cooling medium inlet communication hole 22a flows along the arrow C direction (gravity direction), and is then discharged to each cooling medium outlet communication hole 22b. For this reason, the fuel cell 10 is cooled by the cooling medium.

  In this case, in the first embodiment, as shown in FIG. 2, the second porous gas diffusion layer 38 b constituting the anode electrode 38 is a fuel gas flow path that allows fuel gas to flow along the inside in the separator surface direction. 40. On the other hand, the first porous gas diffusion layer 36b constituting the cathode electrode 36 constitutes an oxidant gas passage 42 through which the oxidant gas flows in the separator surface direction along the inside.

  The resin frame member 32 is provided with a fuel gas introduction portion 46a for supplying fuel gas to the end surface 38be1 of the second porous gas diffusion layer 38b between the first resin sheet member 32a and the second resin sheet member 32b. It has been. Between the first resin sheet member 32a and the second resin sheet member 32b, a fuel gas outlet 46b for discharging the fuel gas from the end face 38be2 of the second porous gas diffusion layer 38b is further provided (FIG. 1). reference).

  Similarly, as shown in FIG. 5, an oxidant gas is introduced between the third resin sheet member 32c and the second resin sheet member 32b to supply an oxidant gas to the end face 36be1 of the first porous gas diffusion layer 36b. A portion 52a is provided. Between the third resin sheet member 32c and the second resin sheet member 32b, an oxidant gas outlet 52b for discharging the oxidant gas from the end face 36be2 of the first porous gas diffusion layer 36b is further provided.

  For this reason, the anode side separator 16 and the cathode side separator 14 do not need to process a flow path system including the fuel gas flow path 40 and the oxidant gas flow path 42. Therefore, the manufacturing work of the anode side separator 16 and the cathode side separator 14 is simplified at once. Thereby, the anode side separator 16 and the cathode side separator 14 can be manufactured easily and satisfactorily, the manufacturing cost of the entire fuel cell 10 is reduced, and the fuel cell 10 can be manufactured economically.

  In particular, the cathode-side separator 14 is configured in a planar shape with a flat separator surface. For this reason, there is an advantage that the manufacturing work of the cathode separator 14 is simplified at a time, and the manufacturing cost is greatly reduced.

  As shown in FIG. 6, the fuel cell 70 according to the second embodiment of the present invention includes an anode separator 72, and a flow path forming plate between the anode separator 72 and the cathode separator 14. 74 is interposed. The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  Similar to the cathode-side separator 14, the anode-side separator 72 is configured in a planar shape with a flat separator surface. The flow path forming plate 74 is formed into a concavo-convex shape by pressing a metal plate into a wave shape. The flow path forming plate 74 is disposed between the adjacent fuel cells 70, that is, between the anode side separator 72 of one fuel cell 70 and the cathode side separator 14 of the other fuel cell 70. A path 24 is formed.

  In the second embodiment configured as described above, the cathode-side separator 14 and the anode-side separator 72 are configured in a planar shape with a flat separator surface. For this reason, the manufacturing work of the cathode side separator 14 and the anode side separator 72 can be simplified at once, and the manufacturing cost can be greatly reduced.

  In the first and second embodiments, the MEA with a frame is sandwiched between a pair of separators, but the present invention is not limited to this. For example, a fuel cell in which a first separator, a first framed MEA, a second separator, a second framed MEA, and a third separator may be used. In this fuel cell, no cooling medium flow path is provided therein, and the cooling medium flow path is provided between adjacent fuel cells (so-called thinning cooling structure).

DESCRIPTION OF SYMBOLS 10,70 ... Fuel cell 12 ... Electrolyte membrane electrode assembly 14 with a frame ... Cathode side separator 16, 72 ... Anode side separator 18a ... Oxidant gas inlet communication hole 18b ... Oxidant gas outlet communication hole 20a ... Fuel gas inlet communication Hole 20b ... Fuel gas outlet communication hole 22a ... Cooling medium inlet communication hole 22b ... Cooling medium outlet communication hole 24 ... Cooling medium flow path 26, 28 ... Seal member 30 ... Electrolyte membrane / electrode structure 32 ... Resin frame members 32a-32c ... resin sheet member 32af, 32cf ... plane part 32ap, 32cp ... convex part 34 ... solid polymer electrolyte membrane 36 ... cathode electrode 36a, 38a ... electrode catalyst layer 36b, 38b ... porous gas diffusion layer 38 ... anode electrode 36be1, 36be2, 38be1, 38be2 ... end face 40 ... fuel gas flow path 42 ... oxidant gas flow path 44 ... adhesive 46 a ... fuel gas introduction part 46b ... fuel gas lead-out part 48a, 48b ... fuel gas connection passage 50a ... fuel gas supply passage 50b ... fuel gas discharge passage 52a ... oxidant gas introduction part 52b ... oxidant gas lead-out parts 54a, 54b ... Oxidant gas connection flow path 56a ... Oxidant gas supply path 56b ... Oxidant gas discharge path 58a, 58b ... Adhesive layer 74 ... Flow path forming plate

Claims (5)

An electrolyte membrane / electrode with a frame having an electrolyte membrane / electrode structure in which electrodes are respectively disposed on both sides of the solid polymer electrolyte membrane, and a resin frame member is provided around the outer periphery of the electrolyte membrane / electrode structure A fuel cell comprising a structure and sandwiching the framed electrolyte membrane / electrode structure with a pair of separators,
The electrode is provided with a porous gas diffusion layer in which a reaction gas flow path is formed to circulate the reaction gas along the separator surface direction.
In the resin frame member, a gas introduction part that supplies the reaction gas to the reaction gas channel inlet side end surface of the porous gas diffusion layer;
A gas outlet for discharging the reaction gas from the end surface on the reaction gas flow path outlet side of the porous gas diffusion layer;
Is provided ,
The resin frame member is laminated in the order of the first resin sheet member, the second resin sheet member, and the third resin sheet member,
Between the first resin sheet member and the second resin sheet member, a fuel gas introduction part that is the gas introduction part and a fuel gas lead part that is the gas lead part are formed,
Wherein the second resin sheet member is provided between the third resin sheet member, characterized Rukoto containing gas outlet portion wherein the oxidant gas inlet is a gas inlet portion is the gas outlet portion are formed A fuel cell. 2. The fuel cell according to claim 1, wherein the resin frame member is provided with a reaction gas inlet communication hole through which the reaction gas flows in a stacking direction intersecting the separator surface direction.
The gas introduction part communicates with the reaction gas inlet communication hole and extends along one side of the resin frame member;
A plurality of passages connected to the connection flow path and the end surface on the reaction gas flow path inlet side of the porous gas diffusion layer;
A fuel cell comprising: 3. The fuel cell according to claim 1, wherein the resin frame member is provided with a reaction gas outlet communication hole through which the reaction gas flows in a stacking direction intersecting the separator surface direction.
The gas outlet portion communicates with the reaction gas outlet communication hole and extends along one side of the resin frame member;
A plurality of passages connected to the connection flow path and the end surface of the porous gas diffusion layer on the reaction gas flow path outlet side;
A fuel cell comprising: The fuel cell according to any one of claims 1 to 3, at least one of said separator adjacent to the framed membrane electrode assembly is characterized in that the separator surface is configured flat plate shape A fuel cell. The fuel cell according to any one of claims 1 to 4 , wherein a seal member is provided on an outer peripheral edge of the separator,
The fuel cell, wherein the sealing member and the resin frame member are welded.

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