JP6661219B2 - Fuel cell and device for manufacturing the same - Google Patents

Description

  The present invention has an electrolyte membrane / electrode structure in which electrodes are provided on both sides of an electrolyte membrane, and a framed electrolyte membrane connected to a frame-shaped insulating member around the outer periphery of the electrolyte membrane / electrode structure. The present invention relates to a fuel cell having an electrode structure and a metal separator, and an apparatus for manufacturing the same.

  Generally, 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 provided on one surface of a solid polymer electrolyte membrane and a cathode electrode is provided on the other surface of the solid polymer electrolyte membrane. ing. The fuel cell is constituted by sandwiching the electrolyte membrane / electrode structure by a separator (bipolar plate). Usually, a fuel cell stack in which a predetermined number of fuel cells are stacked is used as, for example, an on-vehicle fuel cell stack.

  Usually, a fuel cell stack has a large number (several tens to several hundreds) of fuel cells stacked. Therefore, for example, Patent Literature 1 discloses a fuel cell and a method of manufacturing the fuel cell, in which a plurality of fuel cells can be easily and quickly assembled, and the assembly operation of the fuel cells can be efficiently performed. Have been.

  In this fuel cell, the joining pin that integrates the cell unit in which the electrolyte membrane / electrode structure and the separator are laminated has a large-diameter flange that engages with one end of the cell unit. Further, the joining pin has a head that engages with the other end side of the cell unit, and a concave portion for joining pin suction holding is formed in the large-diameter flange portion. Then, by sucking the concave portion, the cell unit can be disposed integrally with each joint pin while the joint pin is positioned and held.

JP 2012-89505 A

  The present invention has been made in connection with this kind of technology, and provides a fuel cell and an apparatus for manufacturing the fuel cell, which can perform assembly work of a fuel cell efficiently and at low cost. The purpose is to:

  The fuel cell according to the present invention has an electrolyte membrane / electrode structure in which electrodes are provided on both sides of the electrolyte membrane, and a frame-shaped insulating member is connected around the outer periphery of the electrolyte membrane / electrode structure. Framed electrolyte membrane / electrode structure, and a metal separator.

  The metal separator includes a first bipolar plate and a second bipolar plate joined to each other, and the frame-shaped insulating member is provided with a welding portion welded to the first bipolar plate by resistance welding. I have.

  Preferably, the first bipolar plate is formed with a convex portion that comes into contact with the welded portion of the frame-shaped insulating member. On the other hand, it is preferable that a hole is formed in the second bipolar plate at a position overlapping the convex portion when viewed from the lamination direction with the first bipolar plate.

  Further, the metal separator is preferably provided with a reaction gas seal line for sealing a reaction gas and a refrigerant seal line for sealing a cooling medium. In that case, it is preferable that the convex portion and the hole are provided outside the reactive gas seal line and the refrigerant seal line.

  Furthermore, the fuel cell manufacturing apparatus according to the present invention includes a pedestal portion on which the framed electrolyte membrane / electrode structure and the metal separator are placed in this order, and a resistance welding contacting the convex portion overlapped with the welded portion. And an electrode section for use. The pedestal has at least an insulating pedestal on which the electrolyte membrane / electrode structure is mounted, and a metal pedestal on which the welded portion is mounted.

  In the fuel cell manufacturing apparatus, the metal pedestal is provided with positioning pins, while the frame-shaped insulating member and the metal separator are formed with positioning holes into which the positioning pins are inserted. Is preferred.

  Further, the fuel cell manufacturing apparatus preferably includes a jig opposed to the pedestal portion with the framed electrolyte membrane / electrode structure and the metal separator interposed therebetween. At this time, it is preferable that one pole of the power supply is connected to the electrode portion for resistance welding, and the other pole of the power supply is connected to a jig.

  Furthermore, in the fuel cell manufacturing apparatus, the resistance welding electrode portion is a first resistance welding electrode portion that is in contact with the first convex portion, and a second convex portion that is different from the first convex portion. And a second resistance welding electrode portion abutting on the convex portion. In this case, it is preferable that one pole of the power supply is connected to the first resistance welding electrode, and the other pole of the power supply is connected to the second resistance welding electrode.

  Further, in the fuel cell manufacturing apparatus, the resistance welding electrode portion is a first resistance welding electrode portion and a second resistance welding electrode portion that are simultaneously in contact with the same convex portion while being insulated from each other. Preferably, it is provided. In this case, it is preferable that one pole of the power supply is connected to the first resistance welding electrode, and the other pole of the power supply is connected to the second resistance welding electrode.

  According to the present invention, the frame-shaped insulating member connected to the outer periphery of the electrolyte membrane / electrode structure is provided with a welding portion welded to the first bipolar plate by resistance welding. For this reason, for example, a cooling process such as the case of welding (joining) by high-frequency heating becomes unnecessary, and the welding time is effectively shortened. Moreover, there is no need to provide a dedicated member at the welded portion, and the configuration can be simplified. This makes it possible to efficiently and satisfactorily assemble the fuel cell unit at low cost.

FIG. 1 is a perspective view illustrating a fuel cell stack in which a fuel cell according to a first embodiment of the present invention is incorporated. It is a perspective explanatory view of the state where a part of the above-mentioned fuel cell was disassembled. FIG. 3 is a sectional view of the fuel cell stack, taken along line III-III in FIG. 2. FIG. 3 is an explanatory front view of a first bipolar plate constituting the fuel cell unit. FIG. 3 is an explanatory front view of a second bipolar plate constituting the fuel cell unit. FIG. 2 is an explanatory exploded perspective view of a main part of the manufacturing apparatus according to the first embodiment of the present invention. FIG. 7 is a cross-sectional explanatory view of the manufacturing apparatus taken along line VII-VII in FIG. 6. FIG. 7 is a cross-sectional explanatory view of the manufacturing apparatus taken along line VIII-VIII in FIG. 6. It is principal part sectional explanatory drawing of the manufacturing apparatus which concerns on 2nd Embodiment of this invention. It is principal part sectional explanatory drawing of the manufacturing apparatus which concerns on 3rd Embodiment of this invention. It is explanatory drawing of the electrode part for resistance welding which comprises the said manufacturing apparatus.

  As shown in FIG. 1, a plurality of fuel cells 10 according to the first embodiment of the present invention are stacked in a horizontal direction (arrow A direction) or a gravity direction (arrow C direction) to form a fuel cell stack 12. I do. The fuel cell stack 12 constitutes, for example, an on-vehicle fuel cell stack, and is mounted on a fuel cell electric vehicle (not shown) or the like.

  In the fuel cell stack 12, a terminal plate 14a, an insulator 16a, and an end plate 18a are sequentially arranged outward at one end in the stacking direction of the fuel cells 10. At the other end in the stacking direction of the fuel cells 10, a terminal plate 14b, an insulator 16b, and an end plate 18b are sequentially disposed outward. At approximately the center of the terminal plates 14a and 14b, terminal portions 20a and 20b extending outward in the stacking direction are provided. The terminal portions 20a, 20b protrude outside the end plates 18a, 18b.

  The end plates 18a and 18b have a horizontally long (or may be vertically long) rectangular shape, and a connection bar 22 is arranged between each side. Both ends of each connection bar 22 are fixed to the inner surfaces of the end plates 18a and 18b via bolts 24, and apply a tightening load in the stacking direction (the direction of arrow A) to the plurality of stacked fuel cells 10. Note that the fuel cell stack 12 may include a housing having the end plates 18a and 18b as end plates, and may be configured to accommodate a plurality of fuel cells 10 in the housing.

  As shown in FIG. 2, the fuel cell 10 includes a framed electrolyte membrane / electrode structure (MEA with frame) 26 and a metal separator 28. The fuel cell stack 12 is configured by alternately stacking the framed electrolyte membrane / electrode structures 26 and the metal separators 28. One end edges of the fuel cell 10 in the direction of arrow B (horizontal direction) communicate with each other in the direction of arrow A, which is the stacking direction, to form an oxidant gas inlet communication hole 30a, a cooling medium inlet communication hole 32a, and a fuel gas outlet. A communication hole 34b is provided.

  The oxidant gas inlet communication hole 30a supplies an oxidant gas, for example, an oxygen-containing gas, the cooling medium inlet communication hole 32a supplies a cooling medium, and the fuel gas outlet communication hole 34b supplies a fuel gas, for example, hydrogen. Discharge contained gas. The oxidant gas inlet communication holes 30a, the cooling medium inlet communication holes 32a, and the fuel gas outlet communication holes 34b are provided in an array in the direction of arrow C (vertical direction).

  A fuel gas inlet communication hole 34a, a cooling medium outlet communication hole 32b, and an oxidant gas outlet communication hole 30b are provided at the other end edges of the fuel cell 10 in the arrow B direction so as to communicate with each other in the arrow A direction. The fuel gas inlet communication hole 34a supplies the fuel gas, the cooling medium outlet communication hole 32b discharges the cooling medium, and the oxidizing gas outlet communication hole 30b discharges the oxidizing gas. The fuel gas inlet communication hole 34a, the cooling medium outlet communication hole 32b, and the oxidizing gas outlet communication hole 30b are arranged in the arrow C direction.

  As shown in FIGS. 2 and 3, the framed electrolyte membrane / electrode structure 26 includes an electrolyte membrane / electrode structure (MEA) 26a. The electrolyte membrane / electrode structure 26a includes, for example, a solid polymer electrolyte membrane (cation exchange membrane) 36 in which a thin film of perfluorosulfonic acid is impregnated with water, and an anode electrode 38 sandwiching the solid polymer electrolyte membrane 36. And a cathode electrode 40. The solid polymer electrolyte membrane 36 may use an HC (hydrocarbon) -based electrolyte in addition to the fluorine-based electrolyte.

  As shown in FIG. 3, the anode electrode 38 includes a first electrode catalyst layer 38a joined to one surface 36a of the solid polymer electrolyte membrane 36, and a first gas diffusion layer laminated on the first electrode catalyst layer 38a. And a layer 38b. The first gas diffusion layer 38b has a larger outer dimension than the solid polymer electrolyte membrane 36 and the first electrode catalyst layer 38a, but has the same outer dimensions as the solid polymer electrolyte membrane 36 and the first electrode catalyst layer 38a. May be provided.

  The cathode electrode 40 has a second electrode catalyst layer 40a joined to the other surface 36b of the solid polymer electrolyte membrane 36, and a second gas diffusion layer 40b laminated on the second electrode catalyst layer 40a. The second gas diffusion layer 40b has a larger outer dimension than the solid polymer electrolyte membrane 36 and the second electrode catalyst layer 40a, but has the same outer dimension as the solid polymer electrolyte membrane 36 and the second electrode catalyst layer 40a. May be provided. The plane sizes of the anode electrode 38 and the cathode electrode 40 may be different from each other.

  The first electrode catalyst layer 38a is formed, for example, by uniformly applying porous carbon particles having a platinum alloy supported on the surface thereof to the surface of the first gas diffusion layer 38b. The second electrode catalyst layer 40a is formed, for example, by uniformly applying porous carbon particles having a platinum alloy supported on the surface thereof to the surface of the second gas diffusion layer 40b. The first gas diffusion layer 38b and the second gas diffusion layer 40b are made of carbon paper, carbon cloth, or the like. The first electrode catalyst layer 38a and the second electrode catalyst layer 40a are formed on both surfaces 36a and 36b of the solid polymer electrolyte membrane 36.

  The framed electrolyte membrane / electrode structure 26 is connected to the frame-shaped insulating member 42 around the outer periphery of the electrolyte membrane / electrode structure 26a. The inner peripheral edge of the frame-shaped insulating member 42 is sandwiched between the outer peripheral edges of the first gas diffusion layer 38b and the second gas diffusion layer 40b with an overlapping portion. In addition, the joining structure of the frame-shaped insulating member 42 and the first gas diffusion layer 38b and the second gas diffusion layer 40b is not limited to this structure, and any structure can be adopted as long as it is joined well. You may. The frame-shaped insulating member 42 is made of, for example, PPS (polyphenylene sulfide), PPA (polyphthalamide), PEN (polyethylene naphthalate), PES (polyether sulfone), LCP (liquid crystal polymer), PVDF (polyvinylidene fluoride) , HDPE (high-density polyethylene), PE (polyethylene), PP (polypropylene), POM (polyoxymethylene), silicone resin, fluororesin, or m-PPE (modified polyphenylene ether resin). The frame-shaped insulating member 42 is not limited to PET (polyethylene terephthalate), PBT (polybutylene terephthalate), modified polyolefin, or resin film, but may be EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, or the like which is an elastomer material. It may be composed of a sealing material such as butyl rubber, natural rubber, styrene rubber, chloroprene, acrylic rubber, a cushion material, or a packing material.

  As shown in FIG. 2, the frame-shaped insulating member 42 has substantially the same outer dimensions as the metal separator 28. The outer shape of the frame-shaped insulating member 42 may be larger than that of the metal separator 28. The frame-shaped insulating member 42 has an oxidant gas inlet communication hole 30a, a cooling medium inlet communication hole 32a, a fuel gas outlet communication hole 34b, a fuel gas inlet communication hole 34a, a cooling medium outlet communication hole 32b, and an oxidant gas outlet communication hole. 30b is provided. A pair of circular positioning holes 44 for MEA positioning are formed at one diagonal position of the frame-shaped insulating member 42.

  The frame-shaped insulating member 42 is provided with a welding portion 45 that is welded to a first bipolar plate 46 described later by resistance welding. The welding portions 45 are set at a total of four positions at the other diagonal position of the frame-shaped insulating member 42 and at a position close to each of the positioning holes 44. The number and position of the welded portions 45 can be variously changed.

  The metal separator 28 includes a first bipolar plate 46 and a second bipolar plate 48 joined to each other. The first bipolar plate 46 and the second bipolar plate 48 are formed, for example, by forming a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, a titanium steel plate, or a metal plate having its metal surface subjected to anticorrosion surface treatment into an uneven shape. It is formed by press molding.

  As shown in FIG. 4, a surface 46a of the first bipolar plate 46 facing the anode electrode 38 of the electrolyte membrane / electrode structure 26a has a fuel gas communicating with the fuel gas inlet communication hole 34a and the fuel gas outlet communication hole 34b. A channel 50 is provided. The fuel gas passage 50 has a plurality of fuel gas passage grooves extending in the direction of arrow B.

  At one diagonal position of the first bipolar plate 46 (near the fuel gas inlet communication hole 34a and the fuel gas outlet communication hole 34b), circular positioning holes 52a, 52a are formed. The positioning hole 52a is disposed coaxially with the positioning hole 44 of the frame-shaped insulating member 42 when viewed in the laminating direction, and has a larger diameter than the positioning hole 44. The first bipolar plate 46 is provided with, for example, four (not limited in number) circular convex portions 53 in contact with the respective welded portions 45 of the frame-shaped insulating member 42 when viewed from the laminating direction. (See FIG. 3).

  As shown in FIG. 2, the outer periphery of the surface 46b of the first bipolar plate 46 is liquid-tightly joined to the outer periphery of the surface 48b of the second bipolar plate 48 by welding, brazing, or the like. A channel 54 is formed. The cooling medium passage 54 has a plurality of cooling medium passage grooves communicating with the cooling medium inlet communication hole 32a and the cooling medium outlet communication hole 32b and extending in the arrow B direction.

  An oxidizing gas channel 56 communicating with the oxidizing gas inlet communication hole 30a and the oxidizing gas outlet communication hole 30b is formed on a surface 48a of the electrolyte membrane / electrode structure 26a of the second bipolar plate 48 facing the cathode electrode 40. Provided. The oxidizing gas passage 56 has a plurality of oxidizing gas passage grooves extending in the arrow B direction.

  As shown in FIG. 5, circular positioning holes 52b, 52b are formed at one diagonal position of the second bipolar plate 48 (near the fuel gas inlet communication hole 34a and the fuel gas outlet communication hole 34b). The positioning hole 52b is arranged coaxially with the positioning hole 52a of the first bipolar plate 46 when viewed in the laminating direction, and has the same opening diameter as the positioning hole 52a. A hole 58 is formed in the second bipolar plate 48 at a position overlapping each convex portion 53 of the first bipolar plate 46 when viewed from the laminating direction.

  On the surfaces 46a and 46b of the first bipolar plate 46, a first seal member 60 is provided integrally or individually around the outer peripheral edge of the first bipolar plate 46. At least a surface 48a of the second bipolar plate 48 is provided with a second seal member 62 integrally or individually around the outer peripheral edge of the second bipolar plate 48.

  The first seal member 60 and the second seal member 62 include, for example, a seal material such as EPDM, NBR, fluoro rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber, and a cushion material. Alternatively, an elastic sealing member such as a packing material is used.

  As shown in FIG. 4, the first seal member 60 is provided with a fuel gas (reactive gas) seal line 60a for sealing the fuel gas (reactive gas) on the surface 46a of the first bipolar plate 46. As shown in FIG. 2, the first seal member 60 is provided with a refrigerant seal line 60b for sealing the cooling medium on the surface 46b of the first bipolar plate 46.

  As shown in FIGS. 2 and 5, the second seal member 62 has an oxidizing gas (reactive gas) seal line 62a for sealing the oxidizing gas (reactive gas) on the surface 48a of the second bipolar plate 48. . The convex portion 53 and the hole 58 are provided outside the fuel gas seal line 60a, the refrigerant seal line 60b, and the oxidizing gas seal line 62a. The positioning holes 44, 52a and 52b are provided outside the fuel gas seal line 60a, the refrigerant seal line 60b and the oxidizing gas seal line 62a.

  FIG. 6 is an exploded perspective view of a main part of a manufacturing apparatus 70 for manufacturing the fuel cell 10 according to the first embodiment of the present invention.

  The manufacturing apparatus 70 includes a pedestal (lower jig) 72 that is placed on the framed electrolyte membrane / electrode structure 26 and the metal separator 28 in this order. As shown in FIGS. 6 and 7, the pedestal portion 72 includes at least an insulating pedestal 74 on which the electrolyte membrane / electrode structure 26 a is mounted and a metal material on which the welded portion 45 of the frame-shaped insulating member 42 is mounted. And a pedestal 76. The insulating pedestal 74 can be made of various insulating resins. Preferably, the insulating pedestal 74 has an outer peripheral end located outside the fuel gas seal line 60a and the oxidizing gas seal line 62a and inside the welded portion 45 (see FIG. 7).

  The metal pedestal 76 is integrally provided with a positioning pin 78 at one diagonal position, and the positioning pin 78 is inserted into the positioning holes 44, 52a and 52b. As shown in FIG. 8, the opening diameter of the positioning hole 44 is set to be equal to the diameter of the positioning pin 78, while the opening diameter of the positioning holes 52a and 52b is larger than the diameter of the positioning pin 78. Is set to A collar member 82 made of insulating resin is provided between the outer periphery of the positioning pin 78 and the inner periphery of the positioning holes 52a and 52b. The collar member 82 has an axial length longer than the thickness of the metal separator 28.

  As shown in FIG. 6, the manufacturing apparatus 70 includes an upper jig 84 placed on the metal separator 28. The upper jig 84 has the same outer dimensions as the metal separator 28 and is formed of a conductive metal. The upper jig 84 is formed with a positioning hole 86 coaxial with the positioning holes 52a and 52b and having an opening diameter equivalent to these. The upper jig 84 has a plurality of holes 88 formed coaxially with the holes 58 of the second bipolar plate 48. The hole 88 preferably has a larger opening diameter than the hole 58.

  The electrode portion 90 for resistance welding is brought into contact with the convex portion 53 of the first bipolar plate 46 superposed on the welded portion 45 of the frame-shaped insulating member 42 from the concave side, and the electrode portion 90 is connected to an upper jig. 84. One electrode of a power supply 92 is electrically connected to the electrode section 90 via a conductor 94, and the other pole of the power supply 92 is electrically connected to the upper jig 84 via a conductor 95. . The electrode section 90 has a cylindrical shape, and the diameter dimension is set to be smaller than the opening diameter of the hole section 58.

  Next, the operation of manufacturing the fuel cell 10 using the manufacturing apparatus 70 will be described below.

  First, the outer periphery of the first bipolar plate 46 and the outer periphery of the second bipolar plate 48 are joined to each other (for example, welded or brazed), and the metal separator 28 is integrally obtained. On the other hand, in the framed electrolyte membrane / electrode structure 26, for example, in a state where the solid polymer electrolyte membrane 36 is joined to the anode 38, the frame-shaped insulating member 42 is sandwiched between the anode 38 and the cathode 40. And so on. The solid polymer electrolyte membrane 36 may be bonded to the cathode electrode 40 in advance, or may be fixed to the frame-shaped insulating member 42. Thus, the framed electrolyte membrane / electrode structure 26 is manufactured.

  Next, as shown in FIGS. 6 to 8, the framed electrolyte membrane / electrode structure 26 is placed on the pedestal portion 72 constituting the manufacturing apparatus 70, and the framed electrolyte membrane / electrode structure 26 is placed on the base 72. A metal separator 28 is placed on top. At this time, as shown in FIG. 8, the positioning pins 78 of the metal pedestal 76 are fitted into the positioning holes 44 provided in the frame-shaped insulating member 42 of the framed electrolyte membrane / electrode structure 26, and The attached electrolyte membrane / electrode structure 26 is positioned.

  Further, after the collar member 82 is externally mounted on the positioning pin 78, the collar member 82 is inserted integrally into the positioning hole 52a of the first bipolar plate 46 and the positioning hole 52b of the second bipolar plate 48. . For this reason, the metal separator 28 is positioned and disposed on the framed electrolyte membrane / electrode structure 26 via the positioning pins 78 and the collar members 82.

  Then, the upper jig 84 is placed on the metal separator 28. As shown in FIG. 8, the upper jig 84 is inserted into the positioning hole 86 with the upper side of the collar member 82 having a length S, and is positioned with respect to the pedestal 72. As shown in FIG. 7, the electrode portion 90 having a spherical tip is in contact with the convex portion 53 of the first bipolar plate 46 from the concave side through the hole portion 58 of the second bipolar plate 48.

  In this state, when the power supply 92 is turned on, energy is concentrated on the convex portion 53 of the first bipolar plate 46, the convex portion 53 is heated, and the welded portion 45 of the frame-shaped insulating member 42 is melted. It is welded to the convex portion 53. That is, the convex portion 53 of the first bipolar plate 46 and the welded portion 45 of the frame-shaped insulating member 42 are joined by resistance welding, for example, micro spot welding.

  In this case, in the first embodiment, a welding portion 45 that is welded to the first bipolar plate 46 by resistance welding is provided on the frame-shaped insulating member 42 connected to the outer periphery of the electrolyte membrane / electrode structure 26a. I have. For this reason, for example, a cooling process such as the case of welding (joining) by high-frequency heating becomes unnecessary, and the welding time is effectively shortened. Moreover, there is no need to provide a dedicated member for the welded portion 45, and the configuration can be simplified.

  Specifically, in the first embodiment, as shown in FIG. 7, the first bipolar plate 46 has a convex portion 53 that contacts the welded portion 45 of the frame-shaped insulating member 42. On the other hand, a hole 58 is formed in the second bipolar plate 48 at a position overlapping the convex portion 53 when viewed from the laminating direction with the first bipolar plate 46. Thereby, an effect is obtained that the assembling work of the fuel cell unit 10 can be performed efficiently and favorably at low cost.

  Further, as shown in FIG. 3, the metal separator 28 is provided with a fuel gas seal line 60a, an oxidizing gas seal line 62a, and a refrigerant seal line 60b. And the convex part 53 and the hole part 58 are provided further outside the fuel gas seal line 60a, the oxidizing gas seal line 62a, and the refrigerant seal line 60b. For this reason, it is possible to suppress dust and the like, which are likely to be generated during resistance welding, from entering the fuel gas flow path 50, the oxidizing gas flow path 56, or the cooling medium flow path 54 as much as possible.

  Still further, as shown in FIG. 7, the insulating pedestal 74 extends to the outside of the fuel gas seal line 60a and the oxidizing gas seal line 62a, and the end is arranged inside the welded portion 45, while the metal is metal. The welding portion 45 is placed on the sex pedestal 76. Therefore, in particular, no current flows through the electrolyte membrane / electrode structure 26a, and the electrolyte membrane / electrode structure 26a can be protected well. In addition, by using the metal pedestal 76, heat at the time of welding can be easily conducted and the cooling function can be promoted, so that the work efficiency can be more easily improved.

  Next, the operation of the fuel cell 10 thus configured will be described below.

  As shown in FIG. 1, in the end plate 18a, an oxidizing gas such as an oxygen-containing gas is supplied to the oxidizing gas inlet communication hole 30a, and a hydrogen-containing gas or the like is supplied to the fuel gas inlet communication hole 34a. Fuel gas is supplied. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 32a.

  As shown in FIG. 2, the oxidizing gas is introduced from the oxidizing gas inlet communication hole 30 a into the oxidizing gas passage 56 of the second bipolar plate 48. Thus, the oxidizing gas flows in the direction of arrow B along the oxidizing gas flow path 56 and is supplied to the cathode 40 of the electrolyte membrane / electrode structure 26a.

  On the other hand, the fuel gas is introduced into the fuel gas channel 50 of the first bipolar plate 46 from the fuel gas inlet communication hole 34a. In the fuel gas flow path 50, the fuel gas flows in the direction of arrow B and is supplied to the anode electrode 38 of the electrolyte membrane / electrode structure 26a.

  Therefore, in the electrolyte membrane / electrode structure 26a, as shown in FIG. 3, the fuel gas supplied to the anode electrode 38 and the oxidant gas supplied to the cathode electrode 40 are mixed with the first electrode catalyst layer 38a and the second electrode catalyst layer 38a. It is consumed by the electrochemical reaction in the two-electrode catalyst layer 40a. Thereby, the power generation of the fuel cell unit 10 is performed.

  Next, as shown in FIG. 2, the oxidizing gas supplied to the cathode electrode 40 and consumed is discharged to the oxidizing gas outlet communication hole 30b. Similarly, the fuel gas supplied to the anode electrode 38 and consumed is discharged to the fuel gas outlet communication hole 34b.

  On the other hand, the cooling medium supplied to the cooling medium inlet communication hole 32a is introduced into the cooling medium passage 54 formed between the first bipolar plate 46 and the second bipolar plate 48 joined to each other. In the cooling medium flow passage 54, the cooling medium moves in the horizontal direction (the direction of arrow B) to cool the entire power generation surface of the electrolyte membrane / electrode structure 26a, and then is discharged to the cooling medium outlet communication hole 32b. .

  FIG. 9 is an explanatory sectional view of a main part of a manufacturing apparatus 100 for manufacturing the fuel cell 10 according to the second embodiment of the present invention. Note that the same components as those of the manufacturing apparatus 70 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

  The manufacturing apparatus 100 is a series spot welding apparatus and includes, for example, a pair of electrode units 90a and 90b. The electrode portion 90a is electrically connected to one pole of the power supply 92 via a conductor 94a, and the electrode portion 90b is electrically connected to the other pole of the power supply 92 via a conductor 94b. The metallic pedestal 76 constituting the pedestal portion 72 functions as a backup electrode.

  In the second embodiment configured as described above, the pair of electrode portions 90a and 90b pass through the respective holes 58 of the second bipolar plate 48 to the respective convex portions 53 of the first bipolar plate 46 from the concave side. Be abutted. Accordingly, each convex portion 53 is heated, and each welded portion 45 of the frame-shaped insulating member 42 is melted and welded to the convex portion 53. Thereby, the welding process can be performed on the two welding portions 45 at the same time, and the effect that the working efficiency is further improved can be obtained.

  In the second embodiment, a pair of electrode parts 90a and 90b is provided, but the present invention is not limited to this, and three or more electrode parts may be used.

  FIG. 10 is an explanatory cross-sectional view of a main part of a manufacturing apparatus 110 for manufacturing the fuel cell 10 according to the third embodiment of the present invention. Note that the same components as those of the manufacturing apparatus 70 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

  The manufacturing apparatus 110 is a series spot welding apparatus, and includes, for example, a pair of electrode sections 112a and 112b as electrode sections for resistance welding. The electrode portion 112a is electrically connected to one pole of the power supply 92 via a conductor 94a, and the electrode portion 112b is electrically connected to the other pole of the power supply 92 via a conductor 94b.

  As shown in FIG. 11, each of the electrode portions 112a and 112b has a semicircular cross section, and is arranged in a generally circular shape adjacent to each other. Although not shown, the electrode portions 112a and 112b are arranged in a state where they are insulated from each other.

  In the third embodiment configured as described above, the pair of electrode portions 112a and 112b pass through the same hole portion 58 of the second bipolar plate 48 in a state of being adjacent to each other and have a convex shape of the first bipolar plate 46. It comes into contact with the portion 53 from the concave side. Therefore, the convex portion 53 is heated by the pair of electrode portions 112a and 112b, and the welded portion 45 of the frame-shaped insulating member 42 is melted and welded to the convex portion 53.

  In the other convex portions 53, the welding portion 45 is joined by the pair of electrode portions 112a and 112b, respectively, similarly to the above-described convex portion 53. Thereby, the welding process can be performed on the four welding portions 45 at the same time, and the effect that the working efficiency is further improved can be obtained.

  In the first to third embodiments, the holes 58 are provided in the second bipolar plate 48, but the present invention is not limited to this. For example, a concave notch may be provided instead of the hole 58. It is also possible to set the outer dimensions of the second bipolar plate 48 smaller than the outer dimensions of the first bipolar plate 46, and to provide the convex portions 53 outside the second bipolar plate 48. That is, the second bipolar plate 48 does not require processing of holes, cutouts, and the like.

Reference Signs List 10: fuel cell 12: fuel cell stack 26: electrolyte membrane / electrode structure with frame 26a: electrolyte membrane / electrode structure 28: metal separator 30a: oxidant gas inlet communication hole 30b: oxidant gas outlet communication hole 32a Cooling medium inlet communication hole 32b Cooling medium outlet communication hole 34a Fuel gas inlet communication hole 34b Fuel gas outlet communication hole 36 Solid polymer electrolyte membrane 38 Anode electrode 40 Cathode electrode 42 Frame-shaped insulating members 44, 52a , 52b, 86 positioning holes 45 welding portions 46, 48 bipolar plates 50 fuel gas channels 53 convex portions 54 cooling medium channels 56 oxidant gas channels 58, 88 hole 60 62 seal member 60a fuel gas seal line 60b refrigerant seal line 62a oxidant gas seal line 70, 100, 110 production equipment 72 pedestal part 74 insulating pedestal 76 metallic pedestal 78 positioning pin 82 collar member 84 upper jigs 90, 90a, 90b, 112a, 112b electrode part 92 power supply

Claims (8)

Electrolyte membrane / electrode structure having a frame having an electrolyte membrane / electrode structure in which electrodes are provided on both sides of the electrolyte membrane, wherein a frame-shaped insulating member is connected around the outer periphery of the electrolyte membrane / electrode structure. And a fuel cell having a metal separator,
The metal separator includes a first bipolar plate and a second bipolar plate joined to each other,
The frame-shaped insulating member is provided with a welding portion that is welded to the first bipolar plate by resistance welding .
On the first bipolar plate, a convex portion that contacts the welded portion of the frame-shaped insulating member is formed.
A fuel cell , wherein a hole is formed in the second bipolar plate at a position overlapping the convex portion when viewed from the laminating direction with the first bipolar plate . The fuel cell according to claim 1 , wherein the metal separator is provided with a reactive gas seal line for sealing a reactive gas, and a refrigerant seal line for sealing a cooling medium.
The fuel cell according to claim 1, wherein the convex portion and the hole are provided outside the reactive gas seal line and the refrigerant seal line. Electrolyte membrane / electrode structure having a frame having an electrolyte membrane / electrode structure in which electrodes are provided on both sides of the electrolyte membrane, wherein a frame-shaped insulating member is connected around the outer periphery of the electrolyte membrane / electrode structure. And a metal separator, wherein the metal separator includes a first bipolar plate and a second bipolar plate joined to each other, and the first bipolar plate is welded to the frame-shaped insulating member. The second bipolar plate has a hole formed at a position overlapping with the protrusion when viewed from the lamination direction with the first bipolar plate, while a convex portion contacting the portion is formed. A fuel cell manufacturing apparatus for manufacturing a fuel cell, comprising:
A pedestal portion which is placed in the order of the framed electrolyte membrane / electrode structure and the metal separator,
An electrode portion for resistance welding to be brought into contact with the convex portion superimposed on the welding portion,
With
The pedestal portion is an insulating pedestal on which at least the electrolyte membrane / electrode structure is mounted,
A metal pedestal on which the welding portion is mounted,
An apparatus for manufacturing a fuel cell, comprising: The fuel cell manufacturing apparatus according to claim 3 , wherein the metal separator is provided with a reaction gas seal line for sealing a reaction gas, and a refrigerant seal line for sealing a cooling medium,
The fuel cell manufacturing apparatus, wherein the convex portion and the hole are provided outside the reactive gas seal line and the refrigerant seal line. A fuel cell manufacturing apparatus according to claim 3 or 4, wherein, while the the metal base, the positioning pins are provided,
A fuel cell manufacturing apparatus, wherein a positioning hole into which the positioning pin is inserted is formed in the frame-shaped insulating member and the metal separator. The fuel cell manufacturing apparatus according to any one of claims 3 to 5 , further comprising a jig opposed to the pedestal portion with the framed electrolyte membrane / electrode structure and the metal separator interposed therebetween. ,
The fuel cell manufacturing apparatus according to claim 1, wherein one pole of the power supply is connected to the resistance welding electrode section, and the other pole of the power supply is connected to the jig. The fuel cell manufacturing apparatus according to any one of claims 3 to 5 , wherein the resistance welding electrode portion is a first resistance welding electrode portion that is in contact with a first protrusion.
A second resistance welding electrode portion abutting on a second convex portion different from the first convex portion;
With
A fuel cell, wherein one pole of a power supply is connected to the first resistance welding electrode section, and the other pole of the power supply is connected to the second resistance welding electrode section. manufacturing device. The fuel cell manufacturing apparatus according to any one of claims 3 to 5 , wherein the resistance welding electrode portions are simultaneously in contact with the same convex portion while being insulated from each other. A first resistance welding electrode portion and a second resistance welding electrode portion;
A fuel cell, wherein one pole of a power supply is connected to the first resistance welding electrode section, and the other pole of the power supply is connected to the second resistance welding electrode section. manufacturing device.

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