JP2009104987A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively simplify an assembly process of a fuel cell, and enable a desired seal function to be ensured with economical and simple construction. <P>SOLUTION: A plurality of rubber bridge parts 52a is formed on the surface 18a of a second metal separator 18 positioned in the vicinity of an oxidizer gas inlet communication hole 20a. A plurality of channel sections for passage 56a which communicate the oxidizer gas inlet communication hole 20a and the oxidizer gas flow path 26 is formed between the rubber bridge parts 52a. In the upper face part 54a of the top of the rubber bridge parts 52a, rigidity of the end edge section 58a of both sides adjacent to the channel sections for passage 56a is set higher than rigidity of the other section 60a. Specifically, the height h1 of the end edge section 58a is set larger than the height h2 of the other section 60a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes an electrolyte / electrode structure in which a pair of electrodes are disposed on both sides of an electrolyte, the electrolyte / electrode structure and a metal separator are stacked, and at least a fuel gas, an oxidant gas, or a cooling medium. The present invention relates to a fuel cell in which a fluid flow path for flowing any fluid in the surface direction of the metal separator and a fluid communication hole for supplying the fluid in the stacking direction are formed in the stacking direction.

  For example, in a polymer electrolyte fuel cell, an electrolyte membrane / electrode structure (MEA) in which an anode side electrode and a cathode side electrode are disposed on both sides of an electrolyte membrane made of a polymer ion exchange membrane is sandwiched by separators. It has a power generation cell. This type of fuel cell is normally used as a fuel cell stack by stacking a predetermined number of power generation cells.

  In the fuel cell described above, a fuel gas flow path (fluid flow path) for flowing a fuel gas (fluid) facing the anode side electrode and an oxidant gas facing the cathode side electrode in the plane of the separator An oxidant gas flow path (fluid flow path) for flowing (fluid) is provided.

  Further, a fuel gas inlet communication hole and a fuel gas outlet communication hole that are fluid communication holes that penetrate the separator in the stacking direction and communicate with the fuel gas flow path, and an oxidant gas flow path An oxidant gas inlet communication hole and an oxidant gas outlet communication hole, which are fluid communication holes communicating with each other, are formed. In addition, a cooling medium flow path (fluid flow path) for cooling the electrolyte membrane / electrode structure is provided between the separators, and a cooling medium inlet communication that penetrates in the stacking direction and communicates with the cooling medium flow path. A hole and a cooling medium outlet communication hole (fluid communication hole) are formed.

  In this case, the fluid channel and the fluid communication hole communicate with each other via a connection channel having parallel grooves or the like in order to allow fluid to flow smoothly and evenly. However, when the separator and the electrolyte membrane / electrode structure are fastened and fixed with a seal member interposed therebetween, the seal member enters the connection flow path, and a desired sealing property can be maintained. In addition, there is a problem that the reaction gas does not flow well.

  Therefore, in the polymer electrolyte fuel cell stack disclosed in Patent Document 1, as shown in FIG. 17, a reaction gas flow path, for example, an oxidant gas flow path 2 meandering in the plane of the separator 1 is formed. ing. The oxidant gas flow channel 2 communicates with an oxidant gas supply through hole 3 and an oxidant gas discharge through hole 4 that penetrate the peripheral edge of the separator 1 in the stacking direction. A packing 5 is disposed in the separator 1, and the through holes 3, 4 and the oxidant gas flow path 2 are communicated with each other in the plane of the separator 1, and other through holes are sealed from these.

  In the connection flow paths 6a and 6b that connect the through holes 3 and 4 and the oxidant gas flow path 2, a SUS plate 7 that is a seal member is disposed so as to cover the connection flow paths 6a and 6b. The SUS plate 7 is configured in a rectangular shape, and ears 7a and 7b are provided at two locations, respectively, and the ears 7a and 7b are fitted into a step 8 formed on the separator 1.

  Thus, in Patent Document 1, since the SUS plate 7 covers the connection flow paths 6a and 6b, the polymer film (not shown) and the packing 5 do not fall into the oxidant gas flow path 2, The desired sealing performance can be ensured, and an increase in the pressure loss of the reaction gas can be prevented.

JP 2001-266911 A

  However, in Patent Document 1 described above, the SUS plate 7 is attached to each of the connection flow paths 6a and 6b of the separator 1, and the attaching operation of the SUS plate 7 is complicated. In particular, when several tens to several hundreds of fuel cells are stacked, there is a problem that the mounting process of the SUS plate 7 becomes considerably complicated and time-consuming, and the cost is significantly increased. .

  The present invention solves this type of problem, and provides a fuel cell capable of effectively simplifying the assembly process of the fuel cell and ensuring a desired sealing function with an economical and simple configuration. The purpose is to provide.

  The present invention includes an electrolyte / electrode structure in which a pair of electrodes are disposed on both sides of an electrolyte, the electrolyte / electrode structure and a metal separator are stacked, and at least a fuel gas, an oxidant gas, or a cooling medium. The present invention relates to a fuel cell in which a fluid flow path for flowing one of the fluids in the surface direction of the metal separator and a fluid communication hole for supplying the fluid in the stacking direction are formed.

  The metal separator is provided with a plurality of rubber wall members for partitioning between the fluid flow path and the fluid communication hole, and the fluid flow path and the fluid communication hole are communicated between the rubber wall members. In addition, the top surface of the top portion of the rubber wall member is set so that the rigidity of at least one end edge portion adjacent to the passage groove is higher than the rigidity of the other portions.

  Moreover, it is preferable that at least one edge part is set to have a dimension in the height direction larger than that of the other part.

  Further, the rubber wall member is divided into three or more block portions between the groove portions for the passage via the dividing groove portion, and the block portion on the side of the passage groove portion is higher than the other block portions. It is preferable that the direction dimension is set large.

  Furthermore, it is preferable that the partitioning groove portion is provided with a partition wall portion that can prevent the flow of fluid from between the block portions.

  Moreover, it is preferable that the metal plate which comprises a metal separator is provided with one or more reinforcement bending parts corresponding to the edge part of a rubber wall member.

  Further, the metal separator is preferably provided with a reinforcing resin member on the back side of the rubber wall member so as to cover the range of the groove portion for the passage.

  According to the present invention, the rubber wall member includes a plurality of rubber wall members that partition the fluid flow path and the fluid communication hole, and the top surface of the top portion of the rubber wall member is at least one edge portion adjacent to the channel groove portion. Is set higher than the rigidity of other parts. For this reason, even if the passage groove portion is set to have a relatively large width in order to flow a necessary amount of fluid, it is possible to prevent the amount of deflection of the separator from increasing corresponding to the passage groove portion. . Therefore, the sealing linear pressure does not decrease, and good sealing performance can be reliably maintained with an economical and simple configuration.

  FIG. 1 is an exploded perspective view of a main part of a fuel cell 10 according to the first embodiment of the present invention. 2 is a cross-sectional explanatory view taken along line II-II in FIG. 1 of the fuel cell stack 12 in which a plurality of fuel cells 10 are stacked in the direction of arrow A. FIG. 3 is a cross-sectional view of the fuel cell stack 12 in FIG. , III-III line cross-sectional explanatory drawing.

  As shown in FIG. 1, in the fuel cell 10, an electrolyte membrane / electrode structure (electrolyte / electrode structure) 14 is sandwiched between first and second metal separators 16 and 18. The first and second metal separators 16 and 18 are made of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or the like.

  One end edge of the fuel cell 10 in the direction of arrow B (horizontal direction in FIG. 1) communicates with each other in the direction of arrow A, which is the stacking direction, and oxidant for supplying an oxidant gas, for example, an oxygen-containing gas. An agent gas inlet communication hole 20a, a cooling medium outlet communication hole 22b for discharging a cooling medium, and a fuel gas outlet communication hole 24b for discharging a fuel gas, for example, a hydrogen-containing gas, are provided in an arrow C direction (vertical direction). Are provided in an array.

  The other end edge in the direction of arrow B of the fuel cell 10 communicates with each other in the direction of arrow A, a fuel gas inlet communication hole 24a for supplying fuel gas, and a cooling medium inlet communication hole for supplying a cooling medium. 22a and an oxidizing gas outlet communication hole 20b for discharging the oxidizing gas are arranged in the direction of arrow C. The oxidant gas inlet communication hole 20a, the oxidant gas outlet communication hole 20b, the cooling medium inlet communication hole 22a, the cooling medium outlet communication hole 22b, the fuel gas inlet communication hole 24a, and the fuel gas outlet communication hole 24b constitute a fluid communication hole. To do.

  As shown in FIGS. 1 and 4, for example, an oxidant gas channel (fluid channel) 26 extending in the direction of arrow B is formed on the surface 16 a of the first metal separator 16 on the electrolyte membrane / electrode structure 14 side. Is provided. The oxidant gas flow path 26 includes a plurality of grooves provided by forming the first metal separator 16 into a wave shape, and the oxidant gas flow path 26, the oxidant gas inlet communication hole 20a, and the oxidant gas. The outlet communication hole 20b communicates with the connection channels 28a and 28b.

  A first seal member (rubber seal member) 32 is integrated with the surfaces 16a and 16b of the first metal separator 16 by baking or injection molding around the outer peripheral end of the first metal separator 16. . The first seal member 32 uses, for example, a seal material such as EPDM, NBR, fluorine rubber, silicon rubber, fluorosilicon rubber, butyl rubber, natural rubber, styrene rubber, chloroplane, or acrylic rubber, a cushion material, or a packing material. To do.

  The first seal member 32 includes a first flat part 34 integrated with the surface 16 a of the first metal separator 16 and a second flat part 36 integrated with the surface 16 b of the first metal separator 16. As shown in FIG. 4, the first flat portion 34 is formed so as to surround the oxidant gas inlet communication hole 20 a and the oxidant gas outlet communication hole 20 b so as to communicate with the oxidant gas flow path 26. On the other hand, the second flat portion 36 is formed by communicating the cooling medium inlet communication hole 22a and the cooling medium outlet communication hole 22b with a cooling medium flow path (described later).

  As shown in FIGS. 1 and 5, the surface 18a of the second metal separator 18 on the electrolyte membrane / electrode structure 14 side communicates with the fuel gas inlet communication hole 24a and the fuel gas outlet communication hole 24b. A fuel gas channel (fluid channel) 40 extending in the direction is formed. The fuel gas channel 40 includes a plurality of grooves, and the fuel gas channel 40 communicates with the fuel gas inlet communication hole 24a and the fuel gas outlet communication hole 24b as described later.

  As shown in FIG. 1, a cooling medium flow path (fluid flow path) communicating with the cooling medium inlet communication hole 22 a and the cooling medium outlet communication hole 22 b is provided on a surface 18 b opposite to the surface 18 a of the second metal separator 18. 46 is formed.

  A second seal member (rubber seal member) 48 is integrated with the surfaces 18 a and 18 b of the second metal separator 18 around the outer peripheral end of the second metal separator 18. The second seal member 48 is made of the same material as the first seal member 32 described above.

  As shown in FIG. 5, the second seal member 48 includes an outer convex seal 50 a provided on the surface 18 a in the vicinity of the outer peripheral end of the second metal separator 18, and inward from the outer convex seal 50 a. An inner convex seal 50b is provided at a predetermined distance. The inner convex seal 50b closes the fuel gas flow path 40.

  A plurality of block-shaped rubber bridge portions (rubber wall members) 52a and 52b are formed on the surface 18a, in the vicinity of the oxidant gas inlet communication hole 20a and the oxidant gas outlet communication hole 20b. As shown in FIGS. 5 and 6, a plurality of passage groove portions 56 a that connect the oxidant gas inlet communication hole 20 a and the oxidant gas flow channel 26 are formed between the rubber bridge portions 52 a.

  The top upper surface portion 54a of the rubber bridge portion 52a has at least one edge portion adjacent to the passage groove portion 56a, in the first embodiment, the rigidity of the edge portions 58a on both sides (both) is equal to that of the other portion 60a. It is set higher than the rigidity. Specifically, the height h1 of the edge part 58a is set to be larger than the height h2 of the other part 60a.

  As shown in FIG. 5, between the rubber bridge portions 52b, a plurality of passage groove portions 56b that similarly connect the oxidant gas outlet communication hole 20b and the oxidant gas flow channel 26 are formed. The top upper surface part 54b of the rubber bridge part 52b is set so that the rigidity of the edge part 58b on both sides adjacent to the passage groove part 56b is higher than the rigidity of the other part 60b. Specifically, the edge portion 58b is set to have a larger dimension in the height direction than the other portion 60b.

  As shown in FIG. 7, on the surface 18b of the second metal separator 18, an outer convex seal 62a that constitutes the second seal member 48, and a cooling medium flow path 46 spaced inward of the outer convex seal 62a. And an inner convex seal 62b provided so as to surround.

  A plurality of rubber bridge portions (rubber wall members) 64a and 64b are formed in the vicinity of the cooling medium inlet communication hole 22a and the cooling medium outlet communication hole 22b. Between each rubber bridge part 64a, a plurality of passage groove parts 66a communicating the cooling medium inlet communication hole 22a and the cooling medium flow path 46 are formed. The top upper surface portion 65a of the rubber bridge portion 64a is set so that the rigidity of the edge portions 68a on both sides (both) adjacent to the passage groove portion 66a is higher than the rigidity of the other portion 70a. Specifically, the edge portion 68a is set to have a larger dimension in the height direction than the other portion 70a.

  Similarly, a plurality of passage groove portions 66b that connect the cooling medium outlet communication hole 22b and the cooling medium flow path 46 are formed between the rubber bridge portions 64b. The top upper surface portion 65b of the rubber bridge portion 64b is set so that the rigidity of the edge portions 68b on both sides adjacent to the passage groove portion 66b is higher than the rigidity of the other portion 70b. Specifically, the edge portion 68b is set to have a larger dimension in the height direction than the other portion 70b.

  As shown in FIGS. 2 and 3, on both surfaces of the second metal separator 18, the rubber bridge portions 52 a and 52 b overlap with a part of the outer convex seal 62 a (sealing convex portion) in the stacking direction. The parts 64a and 64b overlap a part of the outer convex seal 50a (sealing convex part) in the stacking direction.

  As shown in FIG. 7, a plurality of passages 72a and 72b communicating with the fuel gas inlet communication hole 24a and the fuel gas outlet communication hole 24b are formed on the surface 18b of the second metal separator 18, respectively. The passages 72a and 72b communicate with the plurality of holes 74a and 74b, and the holes 74a and 74b communicate with the fuel gas flow path 40 provided on the surface 18a (see FIG. 5).

  As shown in FIG. 1, the electrolyte membrane / electrode structure 14 includes, for example, a solid polymer electrolyte membrane 80 in which a perfluorosulfonic acid thin film is impregnated with water, and an anode side sandwiching the solid polymer electrolyte membrane 80 An electrode 82 and a cathode side electrode 84 are provided. The surface area of the anode side electrode 82 is set to be smaller than the surface areas of the cathode side electrode 84 and the solid polymer electrolyte membrane 80, and constitutes a so-called step MEA.

  The anode side electrode 82 and the cathode side electrode 84 are composed of a gas diffusion layer made of carbon paper or the like, and an electrode catalyst layer in which porous carbon particles having a platinum alloy supported on the surface are uniformly applied to the surface of the gas diffusion layer. And have. The electrode catalyst layers are bonded to both surfaces of the solid polymer electrolyte membrane 80 so as to face each other with the solid polymer electrolyte membrane 80 interposed therebetween.

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

  First, as shown in FIG. 1, a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 24a, and an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 20a. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 22a.

  For this reason, as shown in FIG. 5, the fuel gas passes through the passage 72a from the fuel gas inlet communication hole 24a of the second metal separator 18, and then moves from the plurality of holes 74a to the surface 18a side to flow the fuel gas. It is introduced into the road 40. In the fuel gas channel 40, the fuel gas is supplied to the anode side electrode 82 constituting the electrolyte membrane / electrode structure 14 while moving in the direction of arrow B.

  On the other hand, as shown in FIG. 2 and FIG. 6, the oxidant gas passes through the groove 56a for each of the rubber bridges 52a provided in the second metal separator 18 from the oxidant gas inlet communication hole 20a and passes through the first metal. It is introduced into the oxidant gas flow path 26 of the separator 16. As a result, the oxidant gas is supplied to the cathode side electrode 84 constituting the electrolyte membrane / electrode structure 14 while moving the oxidant gas flow path 26 in the direction of arrow B as shown in FIGS. The

  Therefore, in the electrolyte membrane / electrode structure 14, the oxidant gas supplied to the cathode side electrode 84 and the fuel gas supplied to the anode side electrode 82 are consumed by an electrochemical reaction in the electrode catalyst layer, thereby generating power. Is done.

  Next, the fuel gas consumed by being supplied to the anode electrode 82 moves from the plurality of holes 74b to the passage 72b, and is then discharged in the direction of arrow A along the fuel gas outlet communication hole 24b. Similarly, the oxidant gas consumed by being supplied to the cathode side electrode 84 is discharged in the direction of arrow A along the oxidant gas outlet communication hole 20b from the passage groove portion 56b of the rubber bridge portion 52b.

  Further, as shown in FIG. 7, the cooling medium supplied to the cooling medium inlet communication hole 22a passes through the passage groove portions 66a of the rubber bridge portion 64a and is cooled between the first and second metal separators 16 and 18. After being introduced into the flow path 46, it flows in the direction of arrow B. The cooling medium cools the electrolyte membrane / electrode structure 14 and then is discharged to the cooling medium outlet communication hole 22b through the passage groove portions 66b of the rubber bridge portion 64b.

  In this case, in the first embodiment, as shown in FIG. 5 and FIG. 6, a plurality of rubber bridge portions 52 a that partition the oxidant gas inlet communication hole 20 a and the oxidant gas flow path 26 are provided, and the rubber Between the bridge portions 52 a, one or more passage groove portions 56 a that communicate the oxidant gas inlet communication hole 20 a and the oxidant gas flow channel 26 are formed. Further, the top surface portion 54a of the top portion of the rubber bridge portion 52a is set such that the rigidity of the edge portions 58a on both sides adjacent to the passage groove portion 56a is higher than the rigidity of the other portions 60a. Specifically, the height h1 of the edge part 58a is set to be larger than the height h2 of the other part 60a.

  Therefore, even if the passage groove portion 56a is set to have a relatively large width in order to flow a necessary amount of oxidant gas, the amount of bending of the second metal separator 18 is large corresponding to the passage groove portion 56a. Can be prevented. Therefore, the rubber bridge portion 52a has an effect that the sealing linear pressure does not decrease and it is possible to reliably maintain a good sealing property.

  The rubber bridge portion 52b that partitions the oxidant gas outlet communication hole 20b and the oxidant gas flow path 26 has the same effect as the rubber bridge portion 52a.

  On the other hand, as shown in FIG. 7, a plurality of rubber bridge portions 64a partitioning between the cooling medium inlet communication hole 22a and the cooling medium flow path 46 are provided, and the cooling medium inlet communication holes are provided between the rubber bridge portions 64a. One or more passage groove portions 66a that communicate between the cooling medium passage 46 and 22a are formed. Further, the top upper surface portion 65a of the rubber bridge portion 64a is set so that the rigidity of the end edge portions 68a on both sides adjacent to the passage groove portion 66a is higher than the rigidity of the other portions 70a.

  Accordingly, even if the passage groove portion 66a is set to have a relatively large width in order to flow a necessary amount of cooling medium, the amount of bending of the second metal separator 18 is increased corresponding to the passage groove portion 66a. The same effect as that of the rubber bridge portion 52a can be obtained.

  The rubber bridge portion 64b that partitions the cooling medium outlet communication hole 22b and the cooling medium flow path 46 has the same effect as the rubber bridge portion 64a.

  Furthermore, in the first embodiment, when the second seal member 48 is integrally formed on the surfaces 18a and 18b of the second metal separator 18, the rubber bridge portions 52a, 52b, 64a and 64b are also integrally formed. Thereby, the sealing molding process is simplified at a time, and the advantage that the productivity of the second metal separator 18 can be effectively improved is obtained.

  In the first embodiment, the outer convex seal 50a, the inner convex seal 50b, the outer convex seal 62a, and the inner convex seal 62b are provided on the surfaces 18a and 18b of the second metal separator 18, respectively. It is not limited to this. For example, the inner convex seal 62b and the rubber bridge portions 64a and 64b are integrally formed on the surface 18b of the second metal separator 18, while only the outer convex seal 50a is formed on the surface 18a of the second metal separator 18. It may be provided. The same applies to the second to seventh embodiments described below.

  FIG. 8 is an explanatory view of one surface 18a of the second metal separator 90 constituting the fuel cell according to the second embodiment of the present invention. In addition, the same referential mark is attached | subjected to the component same as the 2nd metal separator 18 which comprises the fuel cell 10 which concerns on 1st Embodiment, and the detailed description is abbreviate | omitted. Similarly, in the third to seventh embodiments described below, the description thereof is omitted.

  A plurality of rubber bridge portions (rubber wall members) 92a and 92b are formed in the vicinity of the oxidant gas inlet communication hole 20a and the oxidant gas outlet communication hole 20b. As shown in FIGS. 8 and 9, the rubber bridge portion 92a is divided into two via a dividing groove portion 94a. The dividing groove 94a is provided with a shielding rubber member 96a that prevents the flow of the oxidant gas.

  In each rubber bridge portion 92a, the rigidity of the edge portion 58a on the passage groove portion 56a side is set to be higher than the rigidity of the other portion 60a on the division groove portion 94a side.

  As shown in FIG. 8, the rubber bridge portion 92b is divided into two via a dividing groove portion 94b. The dividing groove 94b is provided with a shielding rubber member 96b that prevents the flow of the oxidant gas. In each rubber bridge portion 92b, the rigidity of the end edge portion 58b on the passage groove portion 56b side is set higher than the rigidity of the other portion 60b on the division groove portion 94b side, similarly to the rubber bridge portion 92a.

  Therefore, as shown in FIG. 10, when the linear pressure fluctuation is compared between the case where the rubber bridge portions 92a and 92b are used and the case where the rubber bridge portion 9 (comparative example) having a constant height dimension is used, In the rubber bridge portion 9 having a constant height, the linear pressure is remarkably reduced particularly between the passage groove portions 56a and 56b.

  On the other hand, in the rubber bridge portions 92a and 92b, the edge portions 58a and 58b are configured to be higher than the other portions 60a and 60b, so that the rigidity is improved and the linear pressure between the channel grooves 56a and 56b is increased. Fluctuations are effectively suppressed. Thereby, in 2nd Embodiment, the dispersion | variation in a linear pressure reduces and the effect that the deformation | transformation of the 2nd metal separator 90 is suppressed effectively is acquired. This effect is the same in the first embodiment, but is the same in the third and subsequent embodiments.

  FIG. 11 is an explanatory view of one surface 18a of the second metal separator 100 constituting the fuel cell according to the third embodiment of the present invention.

  A plurality of rubber bridge portions (rubber wall members) 102a and 102b are formed in the vicinity of the oxidant gas inlet communication hole 20a and the oxidant gas outlet communication hole 20b. As shown in FIGS. 11 and 12, the rubber bridge portion 102a is divided into three parts, for example, via two dividing groove parts 104a. Each dividing groove 104a is provided with a shielding rubber member 106a that blocks the flow of the oxidant gas.

  Each rubber bridge portion 102a is substantially divided into three block portions 108a, 110a and 108a, and the block portions 108a, 108a on the channel groove portion 56a side are higher than the other block portions 110a. The dimension of is set large.

  Similarly, the rubber bridge portion 102b is divided into three block portions 108b, 110b and 108b via two dividing groove portions 104b. Each dividing groove 104b is provided with a shielding rubber member 106b, and the block 108b, 108b on the passage groove 56b side is set to have a larger dimension in the height direction than the other block 110b.

  In the third embodiment configured in this way, the block portions 108a and 108b on the side of the passage groove portions 56a and 56b are set to have dimensions in the height direction larger than those of the other block portions 110a and 110b. For this reason, the same effects as those of the first and second embodiments can be obtained, such as the deformation of the passage groove portions 56a and 56b can be effectively prevented.

  FIG. 13 is a cross-sectional explanatory view of a main part of a second metal separator 120 constituting a fuel cell according to the fourth embodiment of the present invention.

  The metal plate 122 constituting the second metal separator 120 corresponds to a portion of the rubber bridge portion 52a, 52b adjacent to the passage groove portion 56a, 56b, that is, corresponds to the edge portion 58a, 58b, and is bent for reinforcement. A portion 124 is provided. Therefore, even if the width dimensions of the channel grooves 56a and 56b are set to be relatively large, the second metal separator 120 prevents partial deformation of the second metal separator 120 due to the tightening load. And good sealing performance can be maintained.

  FIG. 14 is an explanatory cross-sectional view of a main part of a second metal separator 130 constituting a fuel cell according to the fifth embodiment of the present invention.

  The second metal separator 130 is provided with rubber bridge portions 102a and 102b. The metal plate 132 constituting the second metal separator 130 is provided with a reinforcing bent portion 134 corresponding to each of the block portions 108a, 108b, 110a and 110b. Thereby, when a load is applied to the rubber bridge portions 102a and 102b, it is possible to prevent the metal plate 132 from being deformed as much as possible and to prevent the entire second metal separator 130 from being deformed. It is done.

  FIG. 15 is an explanatory cross-sectional view of a main part of a second metal separator 140 constituting a fuel cell according to the sixth embodiment of the present invention.

  The second metal separator 140 has rubber bridge portions 52a and 52b, and on the back side of the rubber bridge portions 52a and 52b, covers the range of the channel grooves 56a and 56b, and corresponds to the edge portions 58a and 58b. A reinforcing resin member 142 extending to the range is provided. For example, PPS (polyphenylene sulfide) is used as the reinforcing resin member 142. Therefore, the second metal separator 140 can be reinforced favorably corresponding to the channel grooves 56a and 56b, and the deformation of the entire second metal separator 140 can be effectively prevented.

  FIG. 16 is an explanatory cross-sectional view of a main part of a second metal separator 150 constituting a fuel cell according to the seventh embodiment of the present invention.

  The second metal separator 150 is provided with rubber bridge portions 102a and 102b, and on the back side of the rubber bridge portions 102a and 102b, the range of the groove portions 56a and 56b for the passage is provided as in the sixth embodiment. A reinforcing resin member 142 is provided to cover. Therefore, in the seventh embodiment, the same effect as in the sixth embodiment can be obtained.

  For example, in the first embodiment, the rigidity of the edge portions 58a and 58b that constitute the rubber bridge portions 52a and 52b and are close to the passage groove portions 56a and 56b is set to be higher than the rigidity of the other portions 60a and 60b. In order to set it high, the height h1 of the edge portions 58a and 58b is set larger than the height h2 of the other portion 60a, but the present invention is not limited to this.

  For example, the edge portions 58a and 58b can be made of a material harder than the other portions 60a. Thereby, even if it is the same height dimension, it becomes possible to set the rigidity of edge part 58a, 58b higher than the rigidity of the other parts 60a, 60b.

It is a principal part disassembled perspective explanatory drawing of the fuel cell which concerns on the 1st Embodiment of this invention. FIG. 2 is a cross-sectional explanatory view taken along the line II-II in FIG. 1 of the fuel cell stack in which the fuel cells are stacked. FIG. 3 is a cross-sectional explanatory view of the fuel cell stack taken along line III-III in FIG. 1. It is front explanatory drawing of the 1st metal separator which comprises the said fuel cell. It is explanatory drawing of one surface of the 2nd metal separator which comprises the said fuel cell. It is a schematic perspective explanatory view of a rubber bridge part constituting the fuel cell. It is explanatory drawing of the other surface of the said 2nd metal separator. It is explanatory drawing of one surface of the 2nd metal separator which comprises the fuel cell which concerns on the 2nd Embodiment of this invention. It is a schematic perspective explanatory view of a rubber bridge part constituting the fuel cell. It is comparison explanatory drawing of the linear pressure fluctuation | variation with the said rubber bridge part and the rubber bridge part of a comparative example. It is explanatory drawing of one surface of the 2nd metal separator which comprises the fuel cell which concerns on the 3rd Embodiment of this invention. It is a schematic perspective explanatory view of a rubber bridge part constituting the fuel cell. It is principal part cross-sectional explanatory drawing of the 2nd metal separator which comprises the fuel cell which concerns on the 4th Embodiment of this invention. It is principal part cross-sectional explanatory drawing of the 2nd metal separator which comprises the fuel cell which concerns on the 5th Embodiment of this invention. It is principal part cross-sectional explanatory drawing of the 2nd metal separator which comprises the fuel cell which concerns on the 6th Embodiment of this invention. It is principal part cross-sectional explanatory drawing of the 2nd metal separator which comprises the fuel cell which concerns on the 7th Embodiment of this invention. It is front view explanatory drawing of the separator which comprises the fuel cell stack which concerns on patent document 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 12 ... Fuel cell stack 14 ... Electrolyte membrane electrode structure 16, 18, 90, 100, 120, 130, 140, 150 ... Metal separator 20a ... Oxidant gas inlet communication hole 20b ... Oxidant gas outlet communication Hole 22a ... Cooling medium inlet communication hole 22b ... Cooling medium outlet communication hole 24a ... Fuel gas inlet communication hole 24b ... Fuel gas outlet communication hole 26 ... Oxidant gas flow path 32, 48 ... Seal member 40 ... Fuel gas flow path 46 ... Cooling medium flow paths 52a, 52b, 64a, 64b, 92a, 92b, 102a, 102b ... Rubber bridge portions 54a, 54b, 65a, 65b ... Top upper surface portions 56a, 56b, 66a, 66b ... channel grooves 58a, 58b, 68a , 68b ... edge portions 60a, 60b, 70a, 70b ... portion 80 ... solid polymer electrolyte membrane 82 ... anode side electrode 84 ... Cathode side electrodes 94a, 94b, 104a, 104b ... Dividing grooves 96a, 96b, 106a, 106b ... Shielding rubber members 108a, 108b, 110a, 110b ... Block parts 124, 134 ... Reinforcing bent parts 142 ... Reinforcing resin Element

Claims (6)

An electrolyte / electrode structure having a pair of electrodes disposed on both sides of the electrolyte, the electrolyte / electrode structure and the metal separator are stacked, and at least one of a fuel gas, an oxidant gas, or a cooling medium A fuel cell in which a fluid flow path for flowing a fluid in a surface direction of the metal separator and a fluid communication hole for supplying the fluid in a stacking direction are formed;
The metal separator is provided with a plurality of rubber wall members that partition between the fluid flow path and the fluid communication hole,
Between the rubber wall members, a channel groove for communicating the fluid flow path and the fluid communication hole is formed, and
In the fuel cell, the top surface of the top portion of the rubber wall member is set so that the rigidity of at least one edge portion adjacent to the channel groove is higher than the rigidity of the other portion.   2. The fuel cell according to claim 1, wherein at least one of the edge portions is set to have a height dimension larger than that of the other portion. 3. The fuel cell according to claim 1, wherein the rubber wall member is divided into three or more block portions through the dividing groove portions between the passage groove portions,
The fuel cell according to claim 1, wherein the block portion on the side of the passage groove is set to have a dimension in a height direction larger than that of the other block portions.   4. The fuel cell according to claim 3, wherein the partitioning groove is provided with a partition wall that can block the flow of the fluid from between the block parts. 5.   5. The fuel cell according to claim 1, wherein the metal plate constituting the metal separator has at least one reinforcing bent portion corresponding to the edge portion of the rubber wall member. A fuel cell provided.   5. The fuel cell according to claim 1, wherein the metal separator is provided with a reinforcing resin member on a back surface side of the rubber wall member so as to cover a range of the passage groove portion. A fuel cell.

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