JP2013171694A - Fuel cell stack - Google Patents

Abstract

A non-circular insulating collar member and a sealing member can be reliably aligned with each other with a simple and economical configuration, and a desired sealing property can be ensured.
A fuel cell stack (10) includes an insulating collar member (84a) disposed in an oxidant gas supply manifold hole (80a) of an end plate (18b), and the insulating collar member (84a) is included in an oxidant gas supply manifold (100). A cylindrical portion 88 having a non-circular cross section is inserted into the peripheral surface. A first O-ring 92a and a second O-ring 92b that are in sliding contact with the inner peripheral surface are attached to the outer peripheral surface of the cylindrical portion 88, and the first O-ring 92a, the second O-ring 92b, and the outer peripheral surface are in phase with each other. Relative phase alignment is performed via a determination mechanism 93.
[Selection] Figure 6

Description

  The present invention includes a fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and at both ends in the stacking direction of the stack in which a plurality of the fuel cells are stacked. Relates to a fuel cell stack in which a terminal plate, an insulating plate and an end plate are disposed.

  For example, a polymer electrolyte fuel cell is a power generation cell in which an electrolyte membrane / electrode structure (MEA) in which an anode electrode and a cathode electrode are arranged on both sides of an electrolyte membrane made of a polymer ion exchange membrane is sandwiched by separators. It has. A fuel cell is usually used as, for example, an in-vehicle fuel cell stack by stacking a predetermined number (for example, several hundreds) of power generation cells.

  In the above fuel cell, a fuel gas flow channel for flowing fuel gas to the anode electrode is provided in the surface of one separator, and an oxidant gas is flowed to the cathode electrode in the surface of the other separator. An oxidant gas flow path is provided. Furthermore, between each power generation cell or between a predetermined number of power generation cells, a cooling medium flow path for flowing a cooling medium is provided along the surface direction of the separator.

  At that time, the fuel cell has a fuel gas supply passage for supplying fuel gas to the fuel gas passage, a fuel gas discharge passage for discharging used fuel gas from the fuel gas passage, an oxidant gas flow. An oxidant gas supply communication hole for supplying an oxidant gas to the passage, an oxidant gas discharge communication hole for discharging the used oxidant gas from the oxidant gas flow path, and a cooling medium for supplying a cooling medium to the cooling medium flow path The supply communication hole and the cooling medium discharge communication hole for discharging the used cooling medium from the cooling medium flow path may be formed so as to penetrate in the stacking direction, thereby forming a so-called internal manifold.

  In this type of internal manifold fuel cell, at least one end plate employs a connection structure for communicating each communication hole with an external manifold member. For example, a fuel cell disclosed in Patent Document 1 includes a laminate including cells 1 as shown in FIG. A terminal 2, an insulator 3, and a pressure plate 4 are disposed at one stacked end portion of the cell 1.

  The cell 1 has a MEA (Membrane Electrode Assembly) 5, and a first separator 6 and a second separator 7 are disposed on both outer sides of the MEA 5. The conduit member 8 has a tube portion 8 b that passes through the inlet / outlet hole of the pressure plate 4, and has a flange portion 8 a on the cell laminate side of the pressure plate 4. The flange portion 8 a is accommodated in the accommodating portion of the terminal 2 and the insulator 3, and is connected as a flow path to the stacked body of the cells 1 through the end face seal 9.

JP 2005-259427 A

  By the way, in the fuel cell described above, it is necessary to ensure airtightness (liquid tightness) between the conduit member 8 and the external manifold member, and usually a seal member (not shown) is interposed at a contact portion between the members. ing.

  In that case, in the fuel cell, due to the shape of each reaction gas flow path, the arrangement position of the communication holes, etc., the opening shape of the communication holes is non-circular, for example, elliptical, oval, rectangular or It may be set to a polygonal shape or the like. For this reason, there exists a possibility that the phase of the conduit | pipe member 8 and a sealing member may shift | deviate, and there exists a problem that desired sealing performance cannot be ensured.

  The present invention solves this type of problem, and with a simple and economical configuration, the phase of the noncircular conduit member (insulating collar member) and the seal member can be reliably matched, and is desired. It is an object of the present invention to provide a fuel cell stack capable of ensuring the sealing performance of

  The present invention includes a fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and at both ends in the stacking direction of the stack in which a plurality of the fuel cells are stacked. Includes a terminal plate, an insulating plate, and an end plate, and at least one of the end plates supplies or discharges a fluid that is a cooling medium or a reactive gas flowing in the stacking direction to or from the external manifold member. The present invention relates to a fuel cell stack in which fluid manifold holes are formed.

  The fuel cell stack includes an insulating collar member disposed in a fluid manifold hole, and the insulating collar member has a cylindrical portion having a non-circular cross section that is inserted into an inner peripheral surface of an external manifold member. ing. A seal member that is in sliding contact with the inner peripheral surface is attached to the outer peripheral surface of the cylindrical portion, and the relative phase alignment between the seal member and the outer peripheral surface is performed via a phase determining mechanism. Yes.

  Further, in this fuel cell stack, the phasing mechanism is formed on the seal member so as to extend in a direction intersecting the circumferential direction of the outer circumferential surface, and is formed on the outer circumferential surface, and the protruding portion is disposed. It is preferable to provide a groove portion.

  Further, in this fuel cell stack, the seal member includes a first seal portion and a second seal portion mounted on the outer peripheral surface, and the phasing mechanism connects the first seal portion and the second seal portion. It is preferable to include a protruding portion that is formed and a groove portion that is formed on the outer peripheral surface and in which the protruding portion is disposed.

  Furthermore, in this fuel cell stack, it is preferable that the protrusions are provided extending in the stacking direction.

  According to the present invention, the insulating collar member has a cylindrical portion having a non-circular cross section, and a seal member is mounted on the outer peripheral surface of the cylindrical portion via a phasing mechanism. For this reason, the outer peripheral surface of the cylindrical portion and the seal member are phase-matched well, and no gap is formed between them. Accordingly, the phase of the non-circular insulating collar member and the sealing member can be reliably matched with a simple and economical configuration, and a desired sealing property can be ensured.

1 is a partially exploded perspective view of a fuel cell stack according to a first embodiment of the present invention. 2 is a schematic cross-sectional explanatory view of the fuel cell stack. FIG. It is a principal part disassembled perspective explanatory drawing of the fuel cell which comprises the said fuel cell stack. It is a principal part disassembled perspective explanatory view by the side of one end plate which comprises the said fuel cell stack. FIG. 5 is a cross-sectional view taken along line VV in FIG. 4 on the one end plate side. It is a principal part disassembled perspective explanatory view by the side of the other end plate which comprises the said fuel cell stack. FIG. 7 is a sectional view taken along line VII-VII in FIG. 6 on the other end plate side. It is a perspective explanatory view of the insulating collar member which constitutes the fuel cell stack concerning the 2nd embodiment of the present invention. 2 is a cross-sectional explanatory view of a fuel cell disclosed in Patent Document 1. FIG.

  As shown in FIGS. 1 and 2, the fuel cell stack 10 according to the first embodiment of the present invention is mounted on a fuel cell vehicle (not shown) such as a fuel cell electric vehicle, for example. Configure the stack.

  In the fuel cell stack 10, a plurality of fuel cells 12 are stacked in the direction of arrow A (horizontal direction) to form a stacked body 13. The plurality of fuel cells 12 may be stacked in the direction of arrow C (vertical direction). As shown in FIG. 2, a terminal plate 14a, an insulating plate 16a, and an end plate 18a are disposed at one end of the stacked body 13 in the stacking direction. A terminal plate 14b, an insulating plate 16b, and an end plate 18b are disposed at the other end of the stacked body 13 in the stacking direction.

  The insulating plates 16a and 16b are formed with recesses 16au and 16bu, and the terminal plates 14a and 14b are accommodated in the recesses 16au and 16bu. Terminals 17a and 17b extend from the terminal plates 14a and 14b in the stacking direction, and the terminals 17a and 17b are exposed to the outside from the end plates 18a and 18b (see FIG. 1). Between the end plate 18a and the insulating plate 16a, a thickness adjusting spacer member (shim member) 19 for adjusting the tightening force in the stacking direction on the stacked body 13 is interposed (see FIG. 2).

  As shown in FIG. 3, in the fuel cell 12, an electrolyte membrane / electrode structure (MEA) 20 is sandwiched between a first separator 22 and a second separator 24. The first separator 22 and the second separator 24 are constituted by, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a vertically long metal plate obtained by applying a surface treatment for corrosion prevention to the metal surface. The first separator 22 and the second separator 24 have a rectangular planar shape, and are formed into a concavo-convex shape by pressing a metal thin plate into a wave shape. In addition, you may comprise the 1st separator 22 and the 2nd separator 24 with a carbon separator, for example.

  At the upper edge of the fuel cell 12 in the direction of arrow C (vertical direction in FIG. 3), an oxidant for supplying an oxidant gas, for example, an oxygen-containing gas, communicates with each other in the direction of arrow A, which is the stacking direction. The agent gas supply communication holes 26a and the fuel gas supply communication holes 28a for supplying a fuel gas, for example, a hydrogen-containing gas, are arranged in the arrow B direction (horizontal direction).

  The lower end edge of the fuel cell 12 in the direction of arrow C communicates with each other in the direction of arrow A, and the oxidant gas discharge communication hole 26b for discharging the oxidant gas, and the fuel gas discharge for discharging the fuel gas. The communication holes 28b are arranged in the arrow B direction. The oxidant gas supply communication hole 26a, the oxidant gas discharge communication hole 26b, the fuel gas supply communication hole 28a, and the fuel gas discharge communication hole 28b have a substantially triangular shape (substantially trapezoidal). For example, it may have a rectangular shape, a polygonal shape, an oval shape, an elliptical shape, or the like.

  A cooling medium supply communication hole 30a for supplying a cooling medium and a cooling medium discharge communication hole 30b for discharging the cooling medium are provided, for example, vertically at both ends of the fuel cell 12 in the direction of arrow B. Provided. The pair of cooling medium supply communication holes 30a and the pair of cooling medium discharge communication holes 30b have a rectangular opening shape, but are not limited thereto. For example, an oblong shape, an elliptical shape, or the like is used. You may have.

  An oxidant gas flow path 32 communicating with the oxidant gas supply communication hole 26a and the oxidant gas discharge communication hole 26b is provided on the surface 22a of the first separator 22 facing the electrolyte membrane / electrode structure 20. The oxidant gas channel 32 allows the oxidant gas to flow downward in the direction of arrow C.

  A fuel gas passage 34 communicating with the fuel gas supply communication hole 28a and the fuel gas discharge communication hole 28b is provided on the surface 24a of the second separator 24 facing the electrolyte membrane / electrode structure 20. The fuel gas channel 34 circulates the fuel gas downward in the direction of arrow C.

  A cooling medium that connects the cooling medium supply communication hole 30a and the cooling medium discharge communication hole 30b between the surface 22b of the first separator 22 and the surface 24b of the second separator 24 constituting the fuel cells 12 adjacent to each other. A flow path 36 is provided. The cooling medium flow path 36 circulates the cooling medium downward in the direction of arrow C, and buffer portions (embossed shapes) 38 a and 38 b are provided above and below (upstream and downstream) of the cooling medium flow path 36.

  The first seal member 40a is integrally or individually provided on the surfaces 22a and 22b of the first separator 22, and the second seal member 40b is integrally formed on the surfaces 24a and 24b of the second separator 24. Or individually. The first seal member 40a and the second seal member 40b are, for example, EPDM, NBR, fluororubber, silicon rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene, acrylic rubber, or other sealant or cushioning material. Or use packing material.

  The electrolyte membrane / electrode structure 20 includes, for example, a solid polymer electrolyte membrane 42 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode electrode 44 and an anode electrode 46 that sandwich the solid polymer electrolyte membrane 42. Prepare.

  The cathode electrode 44 and the anode electrode 46 are an electrode catalyst formed by uniformly applying a gas diffusion layer made of carbon paper or the like and porous carbon particles having a platinum alloy supported on the surface to the surface of the gas diffusion layer. With layers. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 42.

  As shown in FIG. 1, a plurality of connecting members 50 are bridged between the end plate 18a and the end plate 18b. The connecting member 50 has a long plate shape, and two connecting members 50 are disposed on the long side of the fuel cell stack 10 and one on the short side of the fuel cell stack 10. Both ends of the connecting member 50 in the direction of arrow A are fixed to side portions of the end plate 18a and the end plate 18b via bolts 52.

  A predetermined tightening load is applied between the end plates 18a and 18b in the stacking direction, and the distance between the end plates 18a and 18b is kept constant.

  As shown in FIG. 4, the end plate 18a includes a cooling medium supply manifold hole (fluid manifold hole) 54a communicating with the pair of cooling medium supply communication holes 30a and a cooling medium communicating with the pair of cooling medium discharge communication holes 30b. A discharge manifold hole (fluid manifold hole) 54b is formed. Similarly, a pair of cooling medium supply manifold holes 56 a and a pair of cooling medium discharge manifold holes 56 b are formed in the spacer member 19.

  As shown in FIGS. 1 and 4, the end plate 18a is provided with an insulating collar member 58a that is integrally inserted into the cooling medium supply manifold holes 54a and 56a, and the cooling medium discharge manifold holes 54b and 56b. The insulating collar member 58b is disposed so as to be integrated therewith.

  As shown in FIGS. 4 and 5, the insulating collar member 58 a includes a cylindrical portion 60 inserted into the cooling medium supply manifold holes 54 a and 56 a and a large-diameter flange portion 62 provided at one end of the cylindrical portion 60. And integrally. An end face seal 63 is interposed between the flange portion 62 and the insulating plate 16a.

  The cylindrical portion 60 has an oval shape or an elliptical shape corresponding to the shape of the cooling medium supply manifold holes 54a and 56a, and is disposed with a gap in the cooling medium supply manifold holes 54a and 56a. There may be no gap.

  The distal end 60a of the cylindrical portion 60 is exposed to the outside from the end face of the end plate 18a, and an O-ring (seal member) 64, which is a radial seal, is disposed in the circumferential groove 60ad on the outer periphery of the distal end 60a. It is mounted via a determination mechanism 65. The O-ring 64 has an oval shape or an elliptical shape.

  The phase determining mechanism 65 has a function of matching the relative phase between the outer peripheral surface of the cylindrical portion 60 and the O-ring 64. As shown in FIG. 1, the phasing mechanism 65 includes a pair of O-rings 64 that extend in the stacking direction in the direction intersecting the circumferential direction of the outer peripheral surface of the cylindrical portion 60 in the first embodiment. (Or 3 or more) projections 64t, and groove portions 60ae formed on the outer peripheral surface of the cylindrical portion 60 and in which the projections 64t are disposed. The pair of protrusions 64t can be set at an arbitrary position.

  One or more, for example, two positioning hole portions 66 are formed in the flange portion 62. A positioning pin 68 is inserted into the positioning hole 66, and the positioning pin 68 is integrally inserted from the spacer member 19 into the positioning hole 70a and the positioning hole 70b formed in the end plate 18a.

  As shown in FIG. 5, the flange portion 62 of the insulating collar member 58 a contacts the end surface of the spacer member 19, and the flange portion 62 is separated from the insulating plate 16 a by the second seal member 40 b of the second separator 24, for example. Pressed and held.

  The insulating collar member 58b is configured in the same manner as the insulating collar member 58a described above, and the same components are denoted by the same reference numerals and detailed description thereof is omitted.

  As shown in FIG. 1, a cooling medium supply manifold (external manifold member) 72 and a cooling medium discharge manifold (external manifold member) 74 are vertically attached to the end plate 18a.

  The cooling medium supply manifold 72 has a downward U-shape, and is provided with connecting hole portions 72a into which the front ends 60a of the cylindrical portions 60 provided on the insulating collar member 58a are fitted at both left and right ends. The connecting hole portion 72a has an oval shape or an oval shape in the opening cross section, and the cylindrical portion 60 is slidably disposed when the O-ring 64 abuts on the inner peripheral surface (see FIG. 5).

  In the cooling medium supply manifold 72, a screw 76 is inserted into a hole 72c formed in a flange portion 72b provided on the outer periphery, and the tip of the screw 76 is screwed into a screw hole 78 formed in the end plate 18a. (See FIGS. 4 and 5).

  As shown in FIG. 1, like the cooling medium supply manifold 72, the cooling medium discharge manifold 74 is provided with a connecting hole portion 74 a into which the distal end 60 a of the cylindrical portion 60 provided in the insulating collar member 58 b is fitted. In the cooling medium discharge manifold 74, a screw 76 is inserted into a hole 74c formed in a flange portion 74b provided on the outer periphery, and the tip of the screw 76 is screwed into a screw hole 78 formed in the end plate 18a. To do.

  As shown in FIG. 6, the end plate 18b has an oxidant gas supply manifold hole (fluid manifold hole) 80a communicating with the oxidant gas supply communication hole 26a and an oxidant gas discharge communicating with the oxidant gas discharge communication hole 26b. A manifold hole (fluid manifold hole) 80b, a fuel gas supply manifold hole (fluid manifold hole) 82a communicating with the fuel gas supply communication hole 28a, and a fuel gas discharge manifold hole (fluid manifold hole) 82b communicating with the fuel gas discharge communication hole 28b Is formed.

  The oxidant gas supply manifold hole 80a, the oxidant gas discharge manifold hole 80b, the fuel gas supply manifold hole 82a, and the fuel gas discharge manifold hole 82b each have a substantially triangular shape (substantially trapezoidal shape).

  The end plate 18b is provided with insulating collar members 84a and 84b inserted into the oxidant gas supply manifold hole 80a and the oxidant gas discharge manifold hole 80b, as well as the fuel gas supply manifold hole 82a and the fuel gas discharge manifold. Insulating collar members 86a and 86b are disposed in the holes 82b.

  As shown in FIGS. 6 and 7, the insulating collar member 84a includes a cylindrical portion 88 inserted into the oxidant gas supply manifold hole 80a, and a large-diameter flange portion 90 provided at one end of the cylindrical portion 88. Is integrated. The cylindrical portion 88 has a substantially triangular shape (substantially trapezoidal shape) corresponding to the shape of the oxidant gas supply manifold hole 80a, and is disposed with a gap in the oxidant gas supply manifold hole 80a. There may be no gap.

  The distal end 88a of the cylindrical portion 88 is exposed to the outside from the end face of the end plate 18b, and a first O-ring (first seal portion) 92a and a second O-ring (secondary seal) are provided on the outer periphery of the distal end 88a. 2 seal portion) 92b is disposed in the circumferential grooves 88ad1 and 88ad2 and is mounted via the phase determining mechanism 93. The first O-ring 92a and the second O-ring 92b have a substantially triangular shape or a substantially trapezoidal shape. Three or more O-rings may be used.

  The phase determining mechanism 93 has a function of matching the relative phases of the outer peripheral surface of the cylindrical portion 88 with the first O-ring 92a and the second O-ring 92b. As shown in FIG. 6, the phasing mechanism 93 is formed on a plurality of protrusions 92t that connect the first O-ring 92a and the second O-ring 92b, and on the outer peripheral surface of the cylindrical part 88. And a plurality of grooves 88ae to be arranged. The protrusion 92t can be set at an arbitrary position, and both ends of the groove 88ae communicate with the circumferential grooves 88ad1 and 88ad2.

  One or more, for example, two positioning hole portions 94 are formed in the flange portion 90. A positioning pin 96 is inserted into the positioning hole 94, and the positioning pin 96 is inserted into a positioning hole 98 formed in the end plate 18b. As shown in FIG. 7, the flange portion 90 of the insulating collar member 84a contacts the end surface of the end plate 18b, and the flange portion 90 is pressed and held by the first seal member 40a of the first separator 22, for example. The

  The insulating collar members 84b, 86a, and 86b are configured in the same manner as the insulating collar member 84a described above, and the same components are denoted by the same reference numerals and detailed description thereof is omitted.

  The end plate 18b includes an oxidant gas supply manifold (external manifold member) 100, an oxidant gas discharge manifold (external manifold member) 102, a fuel gas supply manifold (external manifold member) 104, and a fuel gas discharge manifold (external manifold member). 106 is attached.

  As shown in FIG. 7, the oxidant gas supply manifold 100 is provided with a connecting hole portion 100 a into which a distal end 88 a of a cylindrical portion 88 provided in the insulating collar member 84 a is fitted. The connecting hole portion 100a has a substantially triangular opening shape (substantially trapezoidal shape), and the cylindrical portion 88 is slidably disposed when the first O-ring 92a and the second O-ring 92b abut on the inner peripheral surface. The

  In the oxidant gas supply manifold 100, a screw 76 is inserted into a hole 100c formed in a flange 100b provided on the outer periphery, and the tip of the screw 76 is screwed into a screw hole 78 formed in the end plate 18b. Match.

  The oxidant gas discharge manifold 102, the fuel gas supply manifold 104, and the fuel gas discharge manifold 106 are configured in the same manner as the oxidant gas supply manifold 100 described above, and a detailed description thereof is omitted.

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

  First, as shown in FIGS. 6 and 7, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas supply manifold 100 of the end plate 18b, and as shown in FIG. 6, a fuel gas supply manifold is provided. A fuel gas such as a hydrogen-containing gas is supplied to 104. Further, as shown in FIG. 1, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium supply manifold 72 of the end plate 18a.

  Therefore, as shown in FIG. 7, the oxidant gas is introduced from the insulating collar member 84a through the oxidant gas supply communication hole 26a into the oxidant gas flow path 32 of the first separator 22. As shown in FIG. 3, the oxidant gas is supplied to the cathode electrode 44 constituting the electrolyte membrane / electrode structure 20 while moving in the direction of arrow C along the oxidant gas flow path 32.

  On the other hand, as shown in FIG. 6, the fuel gas is introduced from the insulating collar member 86a through the fuel gas supply communication hole 28a into the fuel gas flow path 34 of the second separator 24 (see FIG. 3). The fuel gas is supplied to the anode electrode 46 constituting the electrolyte membrane / electrode structure 20 while moving in the arrow C direction along the fuel gas flow path 34.

  Therefore, in the electrolyte membrane / electrode structure 20, the oxidant gas supplied to the cathode electrode 44 and the fuel gas supplied to the anode electrode 46 are consumed by an electrochemical reaction in the electrode catalyst layer to generate power. Is called.

  Next, the oxidant gas supplied to and consumed by the cathode electrode 44 is discharged in the direction of arrow A along the oxidant gas discharge communication hole 26b. On the other hand, the fuel gas supplied to and consumed by the anode electrode 46 is discharged in the direction of arrow A along the fuel gas discharge communication hole 28b.

  Further, as shown in FIGS. 1 and 3, the cooling medium is supplied from the insulating collar member 58a to the cooling medium supply communication hole 30a and introduced into the cooling medium flow path 36 between the first separator 22 and the second separator 24. And circulates in the direction of arrow C. After cooling the electrolyte membrane / electrode structure 20, the cooling medium is discharged to the cooling medium discharge communication hole 30b.

  In this case, in the first embodiment, as shown in FIG. 6, for example, the insulating collar member 84a is inserted into the oxidant gas supply manifold hole 80a, and the tubular portion constituting the insulating collar member 84a is formed. 88 has a substantially triangular shape (substantially trapezoidal shape). A first O-ring 92 a and a second O-ring 92 b are attached to the outer peripheral surface of the cylindrical portion 88 via a phasing mechanism 93.

  Specifically, the phasing mechanism 93 is formed on the projecting portion 92t extending in the stacking direction by connecting the first O-ring 92a and the second O-ring 92b to each other and the outer peripheral surface of the cylindrical portion 88, and the projecting portion And a groove 88ae in which 92t is disposed.

  Therefore, the outer peripheral surface of the cylindrical portion 88 and the first O-ring 92a and the second O-ring 92b are relatively phase-matched easily and accurately, and the outer peripheral surface of the cylindrical portion 88 and the first O-ring 92a are aligned. In addition, no gap is formed between the second O-ring 92b and the second O-ring 92b.

  Accordingly, the phases of the non-circular insulating collar member 84a and the first O-ring 92a and the second O-ring 92b can be reliably matched with a simple and economical configuration, and a desired sealing property can be secured. The effect that it becomes possible is obtained.

  The other insulating collar members 58a, 58b, 84b, 86a, and 86b can obtain the same effects as those of the insulating collar member 84a. Further, the seal member is not limited to the O-ring, and may be an elastic seal having a crimping margin.

  FIG. 8 is an explanatory view of an insulating collar member 120 constituting a fuel cell stack according to the second embodiment of the present invention.

  The insulating collar member 120 integrally includes a cylindrical portion 122 and a large-diameter flange portion 123 provided at one end of the cylindrical portion 122. The cylindrical part 122 has a substantially triangular cross section.

  A circumferential groove 122ad is formed on the outer periphery of the distal end 122a of the cylindrical portion 122, and a substantially triangular O-ring (seal member) 124, which is a radial seal, is interposed in the circumferential groove 122ad via a phasing mechanism 126. Is attached.

  The phase determining mechanism 126 has a function of matching the relative phase between the outer peripheral surface of the cylindrical portion 122 and the O-ring 124. The phase determining mechanism 126 is formed on the outer peripheral surface of the plurality of protrusions 124a, 124b, 124c and 124d whose one end is provided on the O-ring 124, and the plurality of protrusions 124a to 124d. Groove part 122ae. The protrusions 124a to 124d can be set at arbitrary positions, and the other ends of the protrusions 124a to 124d are integrally connected.

  In the second embodiment configured as described above, the O-ring 124 is externally provided on the cylindrical portion 122 of the insulating collar member 120 via the phasing mechanism 126. For this reason, the same effect as the fuel cell stack 10 according to the first embodiment is obtained.

  In the first and second embodiments, as the non-circular insulating collar members, the elliptical insulating collar members 58a and 58b and the substantially triangular insulating collar members 84a, 84b, 86a, 86b and 120 are used. However, it is not limited to this shape. For example, an insulative color member having a polygonal shape such as a square shape or a rhombus shape can be used.

DESCRIPTION OF SYMBOLS 10 ... Fuel cell stack 12 ... Fuel cell 13 ... Laminated body 18a, 18b ... End plate 19 ... Spacer member 20 ... Electrolyte membrane electrode assembly 22, 24 ... Separator 26a ... Oxidant gas supply communication hole 26b ... Oxidant gas discharge Communication hole 28a ... Fuel gas supply communication hole 28b ... Fuel gas discharge communication hole 30a ... Cooling medium supply communication hole 30b ... Cooling medium discharge communication hole 32 ... Oxidant gas flow path 34 ... Fuel gas flow path 36 ... Cooling medium flow path 40a , 40b ... sealing member 42 ... solid polymer electrolyte membrane 44 ... cathode electrode 46 ... anode electrode 50 ... coupling member 54a, 56a ... cooling medium supply manifold hole 54b, 56b ... cooling medium discharge manifold hole 58a, 58b, 84a, 84b, 86a, 86b, 120 ... insulating collar members 60, 88, 122 ... cylindrical portion 60a ... tip 60a e, 88ae, 122ae ... groove portions 62, 90, 123 ... flange portions 64, 92a, 92b, 124 ... O-rings 64t, 92t, 124a-124d ... projection portions 65, 93, 126 ... phase determining mechanism 72 ... cooling medium supply manifold 74 ... Cooling medium discharge manifold 80a ... Oxidant gas supply manifold hole 80b ... Oxidant gas discharge manifold hole 82a ... Fuel gas supply manifold hole 82b ... Fuel gas discharge manifold hole 100 ... Oxidant gas supply manifold 102 ... Oxidant gas discharge manifold 104 ... Fuel gas supply manifold 106 ... Fuel gas discharge manifold

Claims (4)

A fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and a terminal plate at both ends in the stacking direction of the stack in which a plurality of the fuel cells are stacked In addition, an insulating plate and an end plate are disposed, and at least one of the end plates has a fluid manifold hole for supplying or discharging a fluid that is a cooling medium or a reaction gas flowing in the stacking direction to or from the external manifold member. A fuel cell stack formed of
An insulating collar member disposed in the fluid manifold hole;
The insulating collar member has a non-circular cylindrical portion inserted into the inner peripheral surface of the outer manifold member,
A seal member that is in sliding contact with the inner peripheral surface is attached to the outer peripheral surface of the cylindrical portion, and the relative phase alignment between the seal member and the outer peripheral surface is performed via a phasing mechanism. A fuel cell stack characterized by 2. The fuel cell stack according to claim 1, wherein the phasing mechanism includes a protrusion provided on the seal member so as to extend in a direction intersecting a circumferential direction of the outer peripheral surface;
A groove portion formed on the outer peripheral surface and in which the protrusion is disposed;
A fuel cell stack comprising: The fuel cell stack according to claim 1 or 2, wherein the seal member includes a first seal portion and a second seal portion attached to the outer peripheral surface,
The phasing mechanism includes a protrusion that connects the first seal portion and the second seal portion;
A groove portion formed on the outer peripheral surface and in which the protrusion is disposed;
A fuel cell stack comprising:   4. The fuel cell stack according to claim 1, wherein the protrusion is provided to extend in the stacking direction. 5.

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