JP5231083B2 - Fuel cell stack - Google Patents

Description

  The present invention relates to a fuel cell stack including a fuel cell in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of an electrolyte and a separator are stacked, and a plurality of the fuel cells are stacked and accommodated in a box.

  For example, a polymer electrolyte fuel cell has an electrolyte membrane / electrode structure (electrolyte / electrode structure) in which an anode side electrode and a cathode side electrode are disposed on both sides of a solid polymer electrolyte membrane made of a polymer ion exchange membrane, respectively. ) Is sandwiched between separators.

  In this type of fuel cell, for example, a fuel cell stack in which several tens to several hundreds of fuel cells are stacked and accommodated in a box is generally employed in order to configure the fuel cell. At that time, in the fuel cell stack, when an impact (external load) in a direction intersecting with the stacking direction of the fuel cells is applied, there is a possibility that a lateral shift occurs in the fuel cell.

  Therefore, for example, in the fuel cell disclosed in Patent Document 1, a single cell in which an MEA is sandwiched between separators is prepared, and a multi-cell assembly and a module frame in which a plurality of single cells are bonded to each other by an adhesive. The module is configured. A terminal (insulator) and an end plate are disposed at both ends of the multi-cell module in the cell stacking direction, and a casing (outer member) is provided outside the multi-cell module with an external restraining member interposed therebetween. It is arranged. Furthermore, the fuel cell stack is configured by fixing the casing with bolts and nuts.

JP 2005-56814 A

  However, in the above-described prior art, a plurality of module frames holding a multi-cell assembly in which a plurality of single cells are bonded with an adhesive, an external restraining member that receives the module frame, and a casing that receives the external restraining member The structure is considerably complicated.

  In addition, there are problems that the assemblability of the fuel cell stack is lowered and exhaust and drainage are difficult. In addition, there is a problem that the outer diameter of the entire fuel cell stack is increased to increase the volume and become heavy.

  The present invention solves this type of problem, and with a simple configuration, the lateral displacement of the fuel cell is reliably prevented against an external load or the inertial force of the fuel cell itself, and with a simple configuration. An object of the present invention is to provide a fuel cell stack capable of reducing the overall size and weight of the stack.

  The present invention relates to a fuel cell stack including a fuel cell in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of an electrolyte and a separator are stacked, and a plurality of the fuel cells are stacked and accommodated in a box It is.

  The fuel cell stack is provided on the outer peripheral portion of the fuel cell, and is provided with a guide portion that protrudes outward from the side portion of the separator, and a protrusion that protrudes into the box. And a guide receiving part for receiving.

  Moreover, it is preferable that the pressure receiving part which receives a load when the corner | angular part of a separator contact | abuts is provided in the at least 1 corner | angular part in a box.

  Furthermore, it is preferable that the pressure receiving portion includes a support shape portion that is curved or bent corresponding to the corner shape of the separator.

  Furthermore, it is preferable that the pressure receiving portion or the guide receiving portion includes a connecting portion for connecting panel members constituting the box.

  The connecting portion is provided at an end of one panel member, and protrudes in a direction that intersects the stacking direction of the fuel cell and extends along the outer surface of the panel, and the other panel adjacent to the one panel member. A concave portion provided at an end of the member, into which the convex portion is inserted, and the one panel member and the other panel member in a state where the convex portion is inserted into the concave portion. It is preferable to provide the receiving part fixed integrally.

  Furthermore, one panel member is provided with the first convex shape portion and the first concave shape portion alternately along the stacking direction, and the other panel member is inserted with the first convex shape portion. It is preferable that the second concave shape portion and the second convex shape portion inserted into the first concave shape portion are alternately provided along the stacking direction.

  Furthermore, a fuel cell stack according to the present invention is provided with a guide portion provided in an outer peripheral portion of the fuel cell and a box, the guide portion contacts and receives a load from the outside, and the fuel cell stack is stacked. And a guide receiving portion that is divided in a direction. The guide receiving portion includes a connecting portion for connecting the panel members constituting the box, and the connecting portion includes a plurality of receiving portions divided in the stacking direction and the receiving portion. And a coupling member for fixing the panel members to each other.

  Moreover, it is preferable that the pressure receiving part which receives a load when the corner | angular part of a separator contact | abuts is provided in the at least 1 corner | angular part in a box.

  Furthermore, it is preferable that the pressure receiving portion includes a support shape portion that is curved or bent corresponding to the corner shape of the separator.

  Furthermore, the other panel member adjacent to the one panel member is provided at the end of the one panel member with a convex portion that intersects with the stacking direction of the fuel cells and projects in a direction along the outer surface of the panel. It is preferable that a concave shape portion into which the convex shape portion is inserted is provided at the end portion.

  One panel member is provided with the first convex shape portion and the first concave shape portion alternately along the stacking direction, and the other panel member is inserted with the first convex shape portion. It is preferable that the second concave shape portion and the second convex shape portion inserted into the first concave shape portion are alternately provided along the stacking direction.

  According to the present invention, when an external load is applied from a direction crossing the stacking direction of the fuel cells, the guide portion provided on the outer peripheral portion of the fuel cell contacts the guide receiving portion in the box. For this reason, the external load can be dispersed well, the local surface pressure of the fuel cell can be reduced, and damage to the fuel cell can be effectively prevented.

  Thus, with a simple configuration, it is possible to reliably prevent the lateral displacement of the fuel cell against an external load, and to reduce the size and weight of the entire fuel cell stack. In addition, since the number of parts can be reduced, it is possible to easily improve the assembly workability, ventilation performance, and drainage performance.

  FIG. 1 is a schematic perspective explanatory view of a fuel cell stack 10 according to the first embodiment of the present invention.

  The fuel cell stack 10 has a plurality of fuel cell units 12 stacked in the direction of arrow A and accommodated in a box 14. The box 14 includes end plates 16a and 16b disposed at both ends of the fuel cell unit 12 in the stacking direction, four side panels (panel members) 18a to 18d disposed on the side of the fuel cell unit 12, And a hinge mechanism 20 for connecting the end plates 16a and 16b and the side panels 18a to 18d to each other. Side panel 18a-18d is comprised with stainless steel (SUS304 etc.), another metal material, or carbon material.

  As shown in FIG. 2, the fuel cell unit 12 includes a first electrolyte membrane (electrolyte) / electrode structure 22a and a second electrolyte membrane / electrode structure 22b, a first separator 24, a second separator 26, and a third separator. 28. The first electrolyte membrane / electrode structure 22a is sandwiched between the first separator 24 and the second separator 26, while the second electrolyte membrane / electrode structure 22b is sandwiched between the second separator 26 and the third separator 28. Pinch.

  The first to third separators 24, 26, and 28 are formed with R portions (corner shape) 29 at the four corners. In addition, although the 1st-3rd separators 24, 26, and 28 are comprised by the metal separator, you may employ | adopt a carbon separator, for example.

  An oxidant gas, for example, an oxygen-containing gas is supplied to one end edge (upper edge) in the long side direction (the arrow C direction in FIG. 2) of the fuel cell unit 12 so as to communicate with each other in the arrow A direction. An oxidant gas inlet communication hole 30a for supplying the fuel gas, for example, a fuel gas inlet communication hole 32a for supplying a hydrogen-containing gas is provided.

  The other end edge (lower end edge) of the long side direction of the fuel cell unit 12 communicates with each other in the direction of arrow A, and the fuel gas outlet communication hole 32b for discharging the fuel gas and the oxidant gas are discharged. An oxidant gas outlet communication hole 30b is provided.

  Two cooling medium inlet communication holes 34a for supplying a cooling medium are provided at one end edge of the fuel cell unit 12 in the short side direction (arrow B direction), and in the short side direction of the fuel cell unit 12 Two cooling medium outlet communication holes 34b for discharging the cooling medium are provided at the other end edge.

  The first electrolyte membrane / electrode structure 22a and the second electrolyte membrane / electrode structure 22b include, for example, a solid polymer electrolyte membrane 36 in which a perfluorosulfonic acid thin film is impregnated with water, and the solid polymer electrolyte membrane 36. The anode side electrode 38 and the cathode side electrode 40 are provided.

  The anode side electrode 38 and the cathode side electrode 40 are uniformly coated on the surface of the gas diffusion layer with a gas diffusion layer (not shown) made of carbon paper or the like and porous carbon particles carrying a platinum alloy on the surface. And an electrode catalyst layer (not shown) formed. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 36.

  A first fuel gas flow path 42 that connects the fuel gas inlet communication hole 32a and the fuel gas outlet communication hole 32b is formed on the surface 24a of the first separator 24 facing the first electrolyte membrane / electrode structure 22a. The first fuel gas channel 42 is constituted by, for example, a plurality of grooves extending in the direction of arrow C. A cooling medium flow path 44 that connects the cooling medium inlet communication hole 34 a and the cooling medium outlet communication hole 34 b is formed on the surface 24 b of the first separator 24. The cooling medium flow path 44 is configured by a plurality of grooves extending in the arrow B direction.

  The surface 26a of the second separator 26 facing the first electrolyte membrane / electrode structure 22a is provided with, for example, a first oxidant gas channel 46 composed of a plurality of grooves extending in the direction of arrow C. The one oxidant gas passage 46 communicates with the oxidant gas inlet communication hole 30a and the oxidant gas outlet communication hole 30b. A second fuel gas channel 48 that connects the fuel gas inlet communication hole 32a and the fuel gas outlet communication hole 32b is formed on the surface 26b of the second separator 26 that faces the second electrolyte membrane / electrode structure 22b.

  A second oxidant gas flow path 50 communicating with the oxidant gas inlet communication hole 30a and the oxidant gas outlet communication hole 30b is provided on a surface 28a of the third separator 28 facing the second electrolyte membrane / electrode structure 22b. . A cooling medium flow path 44 is integrally formed on the surface 28 b of the third separator 28 so as to overlap the surface 24 b of the first separator 24.

  A first seal member 52 is integrally formed on the surfaces 24 a and 24 b of the first separator 24 around the outer peripheral edge of the first separator 24. On the surfaces 26a and 26b of the second separator 26, the second seal member 54 is integrally formed around the outer peripheral edge of the second separator 26, and on the surfaces 28a and 28b of the third separator 28, A third seal member 56 is integrally formed around the outer peripheral edge of the third separator 28.

  As shown in FIG. 2, a plurality of resin load receivers 60 are integrated with the outer periphery of the first separator 24. Each load receiving portion 60 is provided with holes 62a and 62b in parallel with each other.

  A plurality of resin load receiving portions 64 and 66 are integrated with the second separator 26 and the third separator 28 in correspondence with positions where the load receiving portions 60 of the first separator 24 overlap with the arrow A direction, respectively. . Holes 68a, 68b and 70a, 70b are formed in the load receiving parts 64, 66 so as to communicate with the holes 62a, 62b of the load receiving part 60 in the direction of arrow A.

  As shown in FIG. 3, the diameters of the holes 62a, 62b are set to be smaller than the diameters of the holes 68a, 68b and 70a, 70b, and at least the load among the load receiving parts 60, 64, 66 is shown. The receiving portion 64 protrudes outward from the other load receiving portions 60 and 66. As will be described later, the load receiving portion 64 receives a load (external load) applied from the outside via the box 14 and constitutes a resin guide portion having a guide function when the fuel cell units 12 are stacked. .

  In addition, all of the load receiving portions 60, 64, and 66 may protrude outward and receive the load by all. Further, the load receiving portion 64 may be provided only in the second separator 26, and the load receiving portions 60 and 66 may not be provided in the first separator 24 and the third separator 28.

  In the fuel cell units 12 that are arranged alternately with respect to the stacking direction, the connecting members, for example, the insulating resin clips 72 are inserted into the holes 62a, 68a, and 70a, and are arranged every other place. In the fuel cell unit 12, the resin clip 72, which is a connection member, is similarly inserted into each of the holes 62b, 68b, and 70b.

  Each of the resin clips 72 has a neck portion 72a that engages with the first separator 24, and a large-diameter flange portion 72b that contacts the third separator 28, whereby the first separator 24, the second separator 26, and the third separator The separator 28 is integrally held in the stacking direction.

  As shown in FIG. 4, the side panels 18 a to 18 d constituting the box 14 are provided with guide receiving portions 80 a to 80 d for contacting the load receiving portion 64 and receiving external loads, respectively. The guide receiving portions 80 a and 80 c are provided at three locations corresponding to the load receiving portion 64, and the guide receiving portions 80 b and 80 d are disposed at one location corresponding to the load receiving portion 64. The guide receiving portions 80a to 80d are configured by ribs that are integrally bulged on the inner surface sides of the side panels 18a to 18d, and extend in the stacking direction (arrow A direction) of the fuel cell unit 12 (see FIG. 1). ).

  A pressure receiving portion 82 is provided at each connecting portion of the side panels 18a to 18d. As shown in FIGS. 4 and 5, the connecting portion of the side panels 18a and 18d has bolt members 84 arranged at predetermined intervals in the direction of arrow A at one rising portion of the side panel 18d. Prepare. Each bolt member 84 is fixed to the rising portion of the side panel 18d by welding such as a spot, and the threaded portion 86 of the bolt member 84 projects outward from the side panel 18d.

  A hole 88 for inserting the threaded portion 86 is formed in the lower edge portion of the side panel 18a at a predetermined interval along the arrow A direction. A resin receiving portion 90 is attached to the rising portion of the side panel 18d by being divided by a bolt member 84. Instead of the resin receiving part 90, a metal receiving part or a rubber receiving part may be used.

  The screw portion 86 of the bolt member 84 is inserted into the hole 88 of the side panel 18a. The side panel 18a and the side panel 18d are connected to each other by screwing the nut 92 to the tip of the screw part 86 exposed to the outside from the hole 88. Connection portions between the side panels 18a and 18b, between the side panels 18b and 18c, and between the side panels 18c and 18d are configured similarly to the connection portion between the side panels 18d and 18a.

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

  First, as shown in FIG. 1, in the fuel cell stack 10, an oxidant gas (air) such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 30a, and a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 32a. Etc. are supplied. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the two cooling medium inlet communication holes 34a.

  As shown in FIG. 2, the oxidant gas is supplied to the oxidant gas inlet communication hole 30 a of the fuel cell unit 12 and moves in the direction of arrow A, and the first oxidant gas flow path 46 and the second oxidant gas flow path 46 of the second separator 26. 3 is introduced into the second oxidant gas flow path 50 of the separator 28. The oxidant gas introduced into the first oxidant gas flow path 46 moves along the cathode side electrode 40 of the first electrolyte membrane / electrode structure 22a, while being introduced into the second oxidant gas flow path 50. The oxidant gas moves along the cathode side electrode 40 of the second electrolyte membrane / electrode structure 22b.

  The fuel gas is introduced into the first fuel gas channel 42 of the first separator 24 and the second fuel gas channel 48 of the second separator 26 from the fuel gas inlet communication hole 32 a of the fuel cell unit 12. Therefore, the fuel gas moves along the anode side electrodes 38 of the first electrolyte membrane / electrode structure 22a and the second electrolyte membrane / electrode structure 22b.

  Therefore, in the first electrolyte membrane / electrode structure 22a and the second electrolyte membrane / electrode structure 22b, the oxidant gas supplied to each cathode side electrode 40 and the fuel gas supplied to each anode side electrode 38 are Then, it is consumed by an electrochemical reaction in an electrode catalyst layer (not shown) and power is generated.

  Next, the oxidant gas supplied to and consumed by each cathode side electrode 40 flows along the oxidant gas outlet communication hole 30 b and is then discharged from the fuel cell stack 10. Similarly, the fuel gas supplied to and consumed by each anode side electrode 38 is discharged to the fuel gas outlet communication hole 32 b, flows, and is discharged from the fuel cell stack 10.

  The cooling medium flows in the direction of arrow B after being introduced into the cooling medium flow path 44 between the fuel cell units 12 from the cooling medium inlet communication hole 34a. After the first electrolyte membrane / electrode structure 22a and the second electrolyte membrane / electrode structure 22b are thinned and cooled, the cooling medium moves through the cooling medium outlet communication hole 34b and is discharged from the fuel cell stack 10.

  By the way, the fuel cell stack 10 is mounted on a vehicle (not shown) for in-vehicle use, and the stacking direction (arrow A direction) is arranged in the vehicle length direction. When an external load F is applied to the fuel cell stack 10 from the side (see FIG. 3), the fuel cell unit 12 moves in the direction of arrow B within the box 14.

  At that time, in each fuel cell unit 12, a load receiving portion 64 is provided on the outer peripheral portion of the second separator 26 so as to protrude outward. For this reason, when each fuel cell unit 12 moves to the side panel 18a side through the external load F, for example, the load receiving portion 64 abuts on the guide receiving portion 80a provided on the side panel 18a. Supported (see FIG. 4).

  On the other hand, a pressure receiving portion 82 is provided at each connecting portion between the side panel 18a and the side panels 18b and 18d. Therefore, when each fuel cell unit 12 moves to the side panel 18a side, each load receiving portion 64 is abutted and supported by the guide receiving portion 80a, and both the upper and lower R portions 29 of the fuel cell unit 12 are It abuts on a resin receiving part 90 constituting each pressure receiving part 82.

  Thus, the external load F is received by the load receiving portion 64, the guide receiving portion 80a, the R portion 29, and the resin receiving portion 90. For this reason, the external load F can be dispersed well, the local surface pressure of each fuel cell unit 12 is reduced, and damage to the fuel cell unit 12 can be effectively prevented.

Therefore, in the fuel cell stack 10, can thereby reliably prevent lateral slippage of the fuel cell unit 12 to an external load weight F, with a simple configuration, reduce the size and weight of the entire fuel cell stack 10 The effect is obtained.

  In addition, the fuel cell stack 10 can easily reduce the number of parts compared to the conventional configuration. For this reason, in addition to the workability of assembling the fuel cell stack 10, it is possible to easily improve ventilation and drainage within the fuel cell stack 10.

  In the first embodiment, the fuel cell unit 12 includes two electrolyte membrane / electrode structures (first and second electrolyte membrane / electrode structures 22a and 22b) and three separators (first to first). 3 separators 24, 26 and 28), but is not limited to this. For example, the fuel cell unit may be composed of one electrolyte membrane / electrode structure and two separators. The same applies to the following second and subsequent embodiments.

  FIG. 6 is a schematic perspective view of a fuel cell stack 100 according to the second embodiment of the present invention, and FIG. 7 is a cross-sectional explanatory view of the fuel cell stack 100. The same components as those of the fuel cell stack 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The fuel cell stack 100 has a plurality of fuel cell units 102 stacked in the direction of arrow A and accommodated in a box 104. The box 104 includes four side panels (panel members) 106 a to 106 d disposed on the side of the fuel cell unit 102. While the side panels 106a and 106c are configured in a flat plate shape, the side panels 106b and 106d are provided with pressure receiving portions 108 that are curved corresponding to the R portions 29 of the fuel cell unit 102 at both ends in the direction of arrow B. The pressure receiving portion 108 constitutes a support shape portion having an arcuate cross section and has a function of receiving an external load when the R portion 29 comes into contact therewith.

  As shown in FIG. 7, each fuel cell unit 102 is provided with two load receiving portions 64 on both sides in the direction of arrow B, and one load receiving portion 64 at both ends (upper and lower ends) in the direction of arrow C. Is provided.

  Guide receiving portions 110 are provided at the connecting portions of the side panels 106 a to 106 d constituting the box 104 in correspondence with the load receiving portions 64 arranged at both ends in the direction of arrow B. This is because the impact load is easily absorbed by the deformation of the connecting portion.

  As shown in FIG. 8, the connecting portions between the side panels 106a and 106d and between the side panels 106c and 106d are integrated with the side panels 106a and 106c at a predetermined interval along the arrow A direction. And two protrusions 114 such as dowels, pins or burrings provided between the nut portions 112.

  A resin receiving portion 116 having a U-shaped cross section is attached to the lower ends of the side panels 106a and 106c. The resin receiving portions 116 are divided in the stacking direction (arrow A direction), and each resin receiving portion 116 is prevented from being detached by the protrusion 114. Instead of the resin receiving part 116, a metal receiving part or a rubber receiving part may be used.

  A plurality of holes 118 are formed at both ends of the side panel 106d in the direction of arrow B corresponding to the positions of the nuts 112. A bolt member 120 is inserted into the hole portion 118, and the bolt member 120 is screwed into the nut portion 112.

  In the second embodiment configured as described above, when an external load is applied from the side of the fuel cell stack 100, each fuel cell unit 102 moves to the side panel 106a, for example.

  For this reason, first, after the load receiving portion 64 provided in each fuel cell unit 102 is abutted and supported by the resin receiving portion 116 constituting the guide receiving portion 110, the R portion 29 is changed to the side panel 106b, Abuttingly supported by the pressure receiving portion 108 of 106d. Accordingly, the external load applied to the fuel cell stack 100 from the side is well dispersed by the load receiving portion 64, the resin receiving portion 116, the R portion 29, and the pressure receiving portion 108.

  Thus, in the second embodiment, the lateral displacement of the fuel cell unit 102 is reliably prevented, and the entire fuel cell stack 100 can be reduced in size and weight with a simple configuration. The same effect as the form can be obtained.

  Furthermore, the resin receiving part 116 is divided into a plurality of parts along the direction of arrow A, which is the stacking direction. For this reason, when the fuel cell unit 102 abuts on the resin receiving portion 116, it is possible to prevent the resin receiving portion 116 from being damaged unnecessarily.

  FIG. 9 is an explanatory cross-sectional view of a fuel cell stack 130 according to the third embodiment of the present invention. Note that the same components as those of the fuel cell stack 100 according to the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the fourth embodiment described below, detailed description thereof is omitted.

  The fuel cell stack 130 stacks a plurality of fuel cell units 102 and accommodates them in a box 132. The box 132 includes side panels 134a to 134d, and guide receiving portions 80a and 80c with which the load receiving portion 64 abuts are provided on the inner wall surfaces of the side panels 134a and 134c. By subjecting the inner wall surfaces of the side panels 134b and 134d to a smoothing process, the load receiving portion 64 is directly slidably disposed.

  Each connecting portion 136 of the side panels 134a to 134d includes a bolt portion 138 that is integrally fixed to the side panels 134b and 134d. The bolt part 138 penetrates the side panels 134 a and 134 c and is exposed to the outside, and the nut 140 is screwed into the tip part of the bolt part 138.

  In the third embodiment configured as described above, the fuel cell unit 102 and the box 132 can distribute the external load by the load receiving portion 64, the guide receiving portions 80a and 80c, the R portion 29, and the pressure receiving portion 108. The same effects as those of the first and second embodiments can be obtained.

  FIG. 10 is a schematic perspective view of a fuel cell stack 150 according to the fourth embodiment of the present invention, and FIG. 11 is a cross-sectional explanatory view of the fuel cell stack 150.

  The fuel cell stack 150 has a plurality of fuel cell units 102 stacked in the direction of arrow A and accommodated in a box 152. The box 152 includes four side panels (panel members) 154a to 154d disposed on the side of the fuel cell unit 102.

  Guide receiving portions 156 are provided at the connecting portions of the side panels 154a to 154d constituting the box 152 so as to correspond to the load receiving portions 64 arranged at both ends in the arrow B direction.

  The side panel 154a (one panel member) has a first convex shape portion 158a and a first concave shape portion 160a on both end faces in the arrow C direction, and the stacking direction of the fuel cell units 102 (arrow A direction). Are provided alternately. The side panel 154b (the other panel member) includes a second concave shape portion 160b into which the first convex shape portion 158a is inserted and a second convex shape portion 158b into which the first concave shape portion 160a is inserted. Are alternately provided along the stacking direction.

  In the connection part between the side panels 154a and 154b, the first and second convex shaped parts 158a and 158b are inserted into the first and second concave shaped parts 160a and 160b, and the side panel 154a and The side panel 154b is fixed integrally with the receiving portion 162.

The receiving portion 162 is made of resin, metal, or rubber, and is divided into a plurality along the stacking direction. As shown in FIG. 12, the side panels 154a, while the first hole portion 16 4 of the bolt inserted through the convex portion 158a is provided, the second convex portion 158b of the side panels 154b, welding A hole 166 is formed. A bolt 168 is fixed to the receiving portion 162 by caulking, welding, FSW (friction stir welding), adhesion, press fitting, or the like.

  On both sides of the bolt 168, convex portions 170 are provided corresponding to the hole portions 166 provided in the second convex shape portion 158b. When the receiving portion 162 is made of metal, the convex portion 170 is used, for example, for projection welding. When the receiving portion 162 is made of resin, the protruding portion 170 functions as a positioning dowel. An R portion 172 (or a flat portion) is formed on the inner surface of the receiving portion 162 (on the fuel cell unit 102 side).

  The receiving portion 162 is disposed inside the side panel 154b, and the convex portion 170 is inserted into the hole portion 166 formed in the second convex shape portion 158b, and, for example, projection welding is performed. For this reason, the receiving part 162 is fixed to the side panel 154b in advance.

  In the side panel 154a, a bolt 168 is inserted into a hole 164 formed in each first convex shape portion 158a in a state in which each first convex shape portion 158a is inserted into the second concave shape portion 160b. The Then, by attaching a washer 174 and a nut 176 to the bolt 168, the side panel 154a is integrally fixed to the side panel 154b.

  In that case, the connection part of side panel 154a, 154b is comprised flatly, and the end surface corner | angular part of side panel 154a does not protrude from the outer surface of the box 152, for example.

  In addition, each connection part between the side panels 154b and 154c, between the side panels 154c and 154d, and between the side panels 154d and 154a is comprised similarly to the connection part between said side panels 154a and 154b. The same reference numerals are assigned to the same reference numerals, and the detailed description thereof is omitted.

  In the fourth embodiment configured as described above, the connecting portions of the side panels 154 a to 154 d do not protrude from the outer surface of the box 152 to the outside. For this reason, for example, when a line such as a harness is arranged close to the outer surface of the box 152, it is possible to favorably avoid disconnection of the line.

  Moreover, the overall dimensions of the box 152 can be approximated to the external dimensions of the fuel cell unit 102 as much as possible. Therefore, the fuel cell stack 150 as a whole can be reduced in size and the box 152 as a whole can be reduced in weight.

  Furthermore, the receiving part 162 is divided in the stacking direction (arrow A direction), and the connecting parts of the side panels 154a to 154d do not overlap each other and join each other. Thereby, as shown in FIG. 13, when the external load F is applied from the side of the fuel cell stack 150 or the inertial force of the separator (not shown) is applied in the same direction as the external load F, While absorbing panel deformation via the plurality of receiving portions 162, for example, it is possible to satisfactorily suppress the occurrence of partial stress concentration on the side panel 154a.

  In addition, in 4th Embodiment, although it adapts to the guide receiving part 156, it is also possible to adapt to the pressure receiving part 82 which comprises the fuel cell stack 10 which concerns on 1st Embodiment, for example.

  Moreover, it replaces with the receiving part 162 and the resin-made receiving parts 180 shown in FIG. 14 can be used. The resin receiving portion 180 has a metal nut member 182 embedded in the center thereof by caulking, press-fitting, fitting, or the like. Resin clips 184 are attached to both sides of the nut member 182. The resin clip 184 is inserted into the hole 166 of the side panel 154b, while the bolt 186 is inserted into the hole 164 via a washer 185 from the outside of the side panel 154a. When the bolt 186 is screwed into the nut member 182, the side panels 154 a and 154 b are integrally fixed via the resin receiving portion 180.

  In the first to fourth embodiments, the R portion 29 is used as the separator corner portion shape, but a substantially linear portion can be used instead of the R portion 29. At that time, the pressure receiving portion 108 is set to a substantially linear shape instead of a curved shape as a support shape portion.

1 is a schematic perspective explanatory view of a fuel cell stack according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of a fuel cell unit constituting the fuel cell stack. FIG. 3 is an enlarged cross-sectional view of a main part of the fuel cell stack. FIG. 3 is a cross-sectional explanatory view of the fuel cell stack. It is a partially exploded perspective view of the box constituting the fuel cell stack. FIG. 5 is a schematic perspective explanatory view of a fuel cell stack according to a second embodiment of the present invention. FIG. 3 is a cross-sectional explanatory view of the fuel cell stack. It is a partially exploded perspective view of the box constituting the fuel cell stack. FIG. 6 is a cross-sectional explanatory view of a fuel cell stack according to a third embodiment of the present invention. It is a schematic perspective view of the fuel cell stack according to the fourth embodiment of the present invention. FIG. 3 is a cross-sectional explanatory view of the fuel cell stack. It is a disassembled perspective explanatory drawing of the side panel and receiving part which comprise the said fuel cell stack. It is operation | movement explanatory drawing when the external load is provided to the said fuel cell stack. It is a disassembled perspective explanatory drawing of the said side panel and another receiving part.

Explanation of symbols

10, 100, 130, 150 ... Fuel cell stack 12, 102 ... Fuel cell unit 14, 104, 132, 152 ... Box 16a, 16b ... End plates 18a-18d, 106a-106d, 134a-134d, 154a-154d ... side Panel 20 ... Hinge mechanism 22a, 22b ... Electrolyte membrane / electrode structure 24, 26, 28 ... Separator 29, 172 ... R part 36 ... Solid polymer electrolyte membrane 38 ... Anode side electrode 40 ... Cathode side electrode 42, 48 ... Fuel gas flow path 44 ... Cooling medium flow path 46, 50 ... Oxidant gas flow path 60, 64, 66 ... Load receiving portion 72 ... Resin clips 80a to 80d, 110, 156 ... Guide receiving portions 82, 108 ... Pressure receiving portion 84 120 ... Bolt members 90, 116, 180 ... Resin receiving portions 92, 140, 176 ... Nuts 11 2 ... Nut part 114 ... Projection part 136 ... Connecting part 138 ... Bolt part 158a, 158b ... Convex shape part 160a, 160b ... Concave shape part 162 ... Receiving part

Claims (4)

A fuel cell stack comprising a fuel cell in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of an electrolyte and a separator are stacked, and a plurality of the fuel cells are stacked and accommodated in a box,
A guide portion provided on an outer peripheral portion of the fuel cell and projecting outward from a side portion of the separator;
A guide receiving portion provided in a protruding manner in the box, the guide portion contacting and receiving a load from the outside;
Equipped with a,
At least one corner in the box is provided with a pressure receiving portion that receives the load when the corner of the separator contacts.
The pressure receiving portion, the fuel cell stack, wherein Rukoto a support shaped portion which is curved or bent to correspond to the corner shape of the separator. 2. The fuel cell stack according to claim 1 , wherein the pressure receiving portion or the guide receiving portion includes a connection portion for connecting panel members constituting the box. The fuel cell stack according to claim 2 , wherein the connecting portion is provided at an end of one of the panel members, and protrudes in a direction that intersects the stacking direction of the fuel cells and extends along the outer surface of the panel.
A concave shaped portion provided at an end of the other panel member adjacent to the one panel member, and into which the convex shaped portion is inserted;
A receiving portion that integrally fixes the one panel member and the other panel member in a state where the convex shape portion is inserted into the concave shape portion,
A fuel cell stack comprising: 4. The fuel cell stack according to claim 3 , wherein the one panel member is provided with first convex portions and first concave portions alternately along the stacking direction,
In the other panel member, a second concave shape portion into which the first convex shape portion is inserted and a second convex shape portion to be inserted into the first concave shape portion are alternately arranged along the stacking direction. A fuel cell stack characterized in that the fuel cell stack is provided.

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