JP2008103220A - Fuel cell stack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell stack in which strength deterioration can effectively be prevented and stress given on a cross-section of a bridging part can be released and separator deformation can be prevented. <P>SOLUTION: A separator 28 is provided with a first fuel gas supplying part 36 as well as a second fuel gas supplying part 60 having a fuel gas supplying communication hole 30, a first pinching part 40 as well as a second pinching part 64 which are connected with the first fuel gas supplying part 36 through a first bridging part 38 and are connected with the second fuel gas supplying part 60 through the first bridging part 62 and pinch an electrolyte-electrode assembly 26, and a first case 44 as well as a second case 68 which are connected with the first pinching part 40 through a second bridging part 42 and are connected with the second pinching part 64 through a second bridging part 66 and have an oxidant gas supplying part 56. The first bridging parts 38, 62 and the second bridging parts 42, 66 are established in an unsymmetrical shape, and a load per a cross-sectional unit area of either of the first bridging parts 38, 62 or the second bridging parts 42, 66 is established smaller than a load of the cross-sectional unit area of the other. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cell stack including a fuel cell in which an electrolyte / electrode assembly configured by sandwiching an electrolyte between an anode electrode and a cathode electrode, and a separator, and a plurality of the fuel cells are stacked.

  In general, a solid oxide fuel cell (SOFC) uses an oxide ion conductor, for example, stabilized zirconia, as an electrolyte, and an electrolyte / electrode assembly in which an anode electrode and a cathode electrode are disposed on both sides of the electrolyte. And sandwiched by separators (bipolar plates). This fuel cell is normally used as a fuel cell stack in which a predetermined number of electrolyte / electrode assemblies and separators are laminated.

  In the above fuel cell, in order to supply fuel gas (for example, hydrogen gas) and oxidant gas (for example, air) to the anode electrode and the cathode electrode constituting the electrolyte-electrode assembly, respectively, A fuel gas passage and an oxidant gas passage are formed along the same.

  For example, as shown in FIG. 16, the flat plate stacked fuel cell disclosed in Patent Document 1 includes a separator 1 that is stacked on a power generation cell (not shown). In the separator 1, left and right manifold portions 2a, 2a and a portion 2b in which a central power generation cell is arranged are connected by connecting portions 2c, 2c. The connecting portions 2c and 2c are flexible by being thin and narrow.

  The manifold portions 2a and 2a are provided with gas holes 3 and 4. One gas hole 3 communicates with the fuel gas passage 3a, and the other gas hole 4 communicates with the oxidant gas passage 4a. ing. The fuel gas passage 3a and the oxidant gas passage 4a extend linearly in the portion 2b, and are opened to a fuel electrode current collector and an air electrode current collector (not shown) near the center of the portion 2b. ing.

JP 2006-120589 A (FIG. 2)

  In Patent Document 1, the connecting portions 2c and 2c are formed thin and narrow in order to provide flexibility to the connecting portions 2c and 2c. For this reason, there are problems that the number of processing steps increases and the manufacturing cost of the separator 1 as a whole increases, the strength of the connecting portions 2c and 2c decreases, and the connecting portions 2c and 2c are easily damaged by stress.

  The present invention solves this type of problem, effectively preventing a decrease in strength, equalizing the stress applied to each bridge, and reliably preventing the deformation and damage of the separator. An object of the present invention is to provide a fuel cell stack capable of satisfying the requirements.

  The present invention relates to a fuel cell stack including a fuel cell in which an electrolyte / electrode assembly configured by sandwiching an electrolyte between an anode electrode and a cathode electrode, and a separator, and a plurality of the fuel cells are stacked. It is.

  The separator sandwiches the electrolyte / electrode assembly, and also supplies a fuel gas supply hole for supplying fuel gas along the electrode surface of the anode electrode and an oxidation gas for supplying oxidant gas along the electrode surface of the cathode electrode. A sandwiching portion provided with an agent gas supply hole, and a first reaction gas supply connected to the sandwiching portion for supplying the fuel gas to the fuel gas supply hole or the oxidant gas to the oxidant gas supply hole A first bridge portion in which a passage is formed, and a first reaction gas supply communication hole connected to the first bridge portion for supplying the fuel gas or the oxidant gas to the first reaction gas supply passage are stacked. A first reaction gas supply unit formed in a direction, and a second reaction connected to the clamping unit for supplying the oxidant gas to the oxidant gas supply hole or the fuel gas to the fuel gas supply hole Gas supply A second bridge portion that is formed, a housing portion that is connected to the second bridge portion and accommodates the electrolyte / electrode assembly, and is provided in the housing portion, and the oxidant gas or the fuel gas And a second reaction gas supply section in which a second reaction gas supply communication hole for supplying the reaction gas to the second reaction gas supply passage is formed in the stacking direction.

  The first bridge portion and the second bridge portion are set in an asymmetric shape, and the load per unit area of one of the first bridge portion and the second bridge portion is the other cross section. It was set to be smaller than the load per unit area.

  In addition, it is preferable that the first bridge portion is restrained by the first reaction gas supply unit and the sandwiching portion, while the second bridge portion is restrained by the second reaction gas supply portion and the sandwiching portion.

  Furthermore, the second bridge part is preferably configured to be shorter and wider than the first bridge part. Since a stress smaller than the cross section of the first bridge portion acts on the cross section of the second bridge portion, the deformation of the separator is prevented, and the second bridge portion is shortened so that the entire separator can be easily made compact. Because it is.

  Furthermore, it is preferable that the second bridge portion is configured to be shorter and more numerous than the first bridge portion. This is because the cross-sectional area of the second bridge portion can be set larger than the cross-sectional area of the first bridge portion, and the entire separator can be easily made compact.

  In the present invention, the second bridge portion has a width equivalent to that of the first bridge portion and is provided so as to extend in a direction intersecting with the extending direction of the first bridge portion.

  Furthermore, in the present invention, at least the first bridge part or the second bridge part is set to a wave shape that can be elastically deformed.

  Furthermore, a plurality of clamping parts are connected to the single first reactive gas supply part via a plurality of first bridge parts, and each clamping part is connected to a single via the second bridge part. It is preferable that a plurality of second reaction gas supply sections are formed in the casing section.

  Moreover, it is preferable that a housing | casing part is comprised cyclically | annularly. This is because the exhaust heat from the exhaust gas can be uniformly transferred to the entire casing, and the reaction gas before being supplied to the electrolyte / electrode assembly can be evenly heated. In addition, the temperature distribution of the stack becomes uniform, and the power generation performance is improved and stabilized.

  In the present invention, since the load per unit area of the cross section of one of the first bridge part and the second bridge part is set to be smaller than the load per unit area of the other cross section, the acting stress Can be relaxed at either bridge. Therefore, the deformation of the separator can be satisfactorily prevented with a simple configuration. Moreover, since the first bridge portion and the second bridge portion are set in an asymmetric shape, for example, the second bridge portion can be shortened, and the entire separator can be easily made compact. .

  Furthermore, in the present invention, the second bridge portion has the same width as the first bridge portion and extends in a direction intersecting with the extending direction of the first bridge portion. The second bridge portions are not opposed to each other, and can be deformed by extending in a direction in which no reaction force is generated. For this reason, the clamping part can be moved in the direction in which the first and second bridge parts are not formed, and the stress acting on the first and second bridge parts can be relieved.

  Moreover, in this invention, the 1st bridge part or the 2nd bridge part is set to the wave shape which can be elastically deformed at least. For this reason, a wave-shaped part can have spring elasticity (stress relaxation function), and it becomes possible to relieve | moderate the stress which acts on a 1st bridge part or a 2nd bridge part favorably. Thereby, while making the whole separator compact, deformation | transformation of the said separator can be prevented favorably.

  FIG. 1 is a schematic perspective view of a fuel cell stack 12 according to a first embodiment of the present invention in which a plurality of fuel cells 10 are stacked in the direction of arrow A, and FIG. 2 is a diagram of the fuel cell stack 12. 1 is a cross-sectional view taken along line II-II.

  The fuel cell 10 is a solid oxide fuel cell and is used for various purposes such as in-vehicle use as well as stationary use. As shown in FIGS. 3 and 4, the fuel cell 10 is provided with a cathode electrode 22 and an anode electrode 24 on both surfaces of an electrolyte (electrolyte plate) 20 made of an oxide ion conductor such as stabilized zirconia, for example. The electrolyte / electrode assembly 26 is provided. The electrolyte / electrode assembly 26 is formed in a disc shape.

  As shown in FIG. 3, the fuel cell 10 includes a plurality of (for example, four) electrolyte / electrode assemblies 26 sandwiched between a pair of separators 28. Between the separators 28, four electrolyte / electrode assemblies are spaced apart at equal angular intervals around the fuel gas supply communication hole 30, which is the center of the separator 28, and concentrically with the fuel gas supply communication hole 30. 26 is arranged.

  Separator 28 has the 1st plate 32 and the 2nd plate 34 which consist of sheet metal, such as stainless steel alloy, for example. The first plate 32 and the second plate 34 are joined to each other by diffusion bonding, laser welding, brazing, or the like.

  As shown in FIGS. 3 and 5, the first plate 32 has a fuel gas supply communication hole (first reaction gas supply communication hole) for supplying fuel gas along the stacking direction (arrow A direction) to the center portion. 30 includes a first fuel gas supply unit (first reaction gas supply unit) 36 formed therein. A relatively large-diameter first sandwiching portion 40 is integrally provided via four first bridge portions 38 that extend radially away from the first fuel gas supply portion 36 at equal angular intervals. The first clamping part 40 is set to have substantially the same dimensions as the electrolyte / electrode assembly 26, and each first clamping part 40 has an annular first housing part 44 via a short second bridge part 42. Are provided integrally.

  As shown in FIG. 5, the first bridge portion 38 and the second bridge portion 42 are set in an asymmetric shape, and the sectional area of the second bridge portion 42 with respect to the sectional area of the first bridge portion 38. Becomes larger. Specifically, as shown in FIG. 4, when the thicknesses of the first bridge portion 38 and the second bridge portion 42 are T1 and T2, respectively, the thickness T1 and width H1 of the first bridge portion 38, The thickness T2 and the width H2 of the two bridge portions 42 are set to have a relationship of width H2> width H1, and have a relationship of thickness T1 × width H1 <thickness T2 × width H2.

  A plurality of protrusions 48 that form fuel gas passages 46 for supplying fuel gas along the electrode surface of the anode electrode 24 are provided on the surface of the first sandwiching portion 40 that contacts the anode electrode 24. The protrusion 48 constitutes a current collector. A fuel gas supply hole 52 that is eccentric to the fuel gas supply communication hole 30 side and that supplies the fuel gas toward the substantially central part of the anode electrode 24 is formed in the approximate center of the first clamping part 40.

  The first casing portion 44 has an oxidant gas supply communication hole (second reaction gas supply communication hole) 54 for supplying an oxidant gas to an oxidant gas supply passage 78 to be described later. A gas supply unit (second reaction gas supply unit) 56 is provided. The first housing portion 44 is provided with a plurality of bolt insertion holes 58 spaced apart by a predetermined angular interval. The fuel gas supply communication hole 30, the first bridge part 38, the first clamping part 40, the second bridge part 42, and the oxidant gas supply communication hole 54 are arranged on a straight line along the separator surface direction.

  As shown in FIGS. 3 and 6, the second plate 34 has a second fuel gas supply part (first reaction gas supply part) 60 in which the fuel gas supply communication hole 30 is formed in the center. A second sandwiching portion 64 having a relatively large diameter is integrally provided via four first bridge portions 62 that extend radially away from the second fuel gas supply portion 60 at equal angular intervals. Similar to the first clamping unit 40, the second clamping unit 64 is set to have substantially the same dimensions as the electrolyte / electrode assembly 26, and each second clamping unit 64 is provided with a short second bridge 66. The annular second casing 68 is integrally provided.

  As shown in FIG. 6, the first bridge portion 62 and the second bridge portion 66 have the same relationship as the first bridge portion 38 and the second bridge portion 42. Specifically, as shown in FIG. 4, when the thicknesses of the first bridge portion 62 and the second bridge portion 66 are T1 and T2, respectively, the thickness T1 and width H1 of the first bridge portion 62, The thickness T2 and the width H2 of the two bridge portions 66 are set to have a relationship of width H2> width H1, and have a relationship of thickness T1 × width H1 <thickness T2 × width H2.

  A plurality of grooves 70 communicating with the fuel gas supply communication hole 30 are radially formed on the surface of the second fuel gas supply part 60 joined to the first fuel gas supply part 36 with the fuel gas supply communication hole 30 as a center. Formed. Each groove portion 70 communicates integrally with the circumferential groove 72, and four fuel gas supply passages (first reaction gas supply passages) 74 communicate with the circumferential groove 72. Each fuel gas supply passage 74 extends from each first bridge portion 62 to the vicinity of the center portion of each second clamping portion 64 and ends corresponding to the fuel gas supply hole 52 of the first plate 32.

  The second casing 68 is provided with an oxidant gas supply part 56 in which an oxidant gas supply communication hole 54 is formed in the stacking direction, and a bolt insertion hole 58. A filling chamber 76 for filling the oxidant gas supplied from the oxidant gas supply communication hole 54 is formed on the surface joined to the first case 44 of the second case 68.

  The filling chambers 76 communicate with oxidant gas supply passages (second reaction gas supply passages) 78 extending from the second bridge portions 66 to the vicinity of the central portion of the second holding portions 64. An oxidant gas supply hole 80 penetrating the second clamping part 64 communicates with the tip of the oxidant gas supply passage 78.

  The first plate 32 has a plurality of protrusions 48 formed by, for example, etching, and the second plate 34 has a groove 70, a circumferential groove 72, a fuel gas supply passage 74, a filling chamber 76, and an oxidant gas. The supply passage 78 is formed by etching, for example.

  As shown in FIG. 3, a deformable elastic passage portion, for example, a conductive felt member (conductive nonwoven fabric such as metal felt) 84 is disposed on the surface of the second plate 34 facing the cathode electrode 22. The felt member 84 forms an oxidant gas passage 86 between the second sandwiching portion 64 and the cathode electrode 22. Instead of the felt member 84, a mesh member (conductive woven fabric such as a metal mesh), foam metal, expanded metal, punching metal, press embossed metal, or the like may be employed. An exhaust gas passage 88 for discharging the reacted fuel gas and oxidant gas as exhaust gas is provided on the outer periphery of the electrolyte / electrode assembly 26.

  As shown in FIG. 7, a first insulating seal 90 for sealing the fuel gas supply communication hole 30 and a second insulating seal 92 for sealing the oxidant gas supply communication hole 54 are provided between the separators 28. Is provided. The first insulating seal 90 and the second insulating seal 92 have high sealing properties and are hard and not easily crushed. For example, a crust component material, a glass material, a composite material of clay and plastic, or the like is used. The second insulating seal 92 is preferably a heat insulating member that prevents diffusion of thermal energy.

  As shown in FIGS. 1 and 2, the fuel cell stack 12 has a substantially disc-shaped first end plate 94 a disposed at one end in the stacking direction of the plurality of fuel cells 10, and a partition wall at the other end in the stacking direction. A plurality of second end plates 94b each having a small diameter and a substantially disk shape with a large number 95 interposed, and a fixing ring 94c having a large diameter and a substantially ring shape. The partition walls 95 have a function of preventing the exhaust gas from diffusing to the outside of the fuel cell 10, while four second end plates 94 b are arranged corresponding to the stack positions of the electrolyte / electrode assemblies 26. .

  The first end plate 94 a and the fixing ring 94 c have a plurality of holes 96 that communicate with the bolt insertion holes 58 of the separator 28. The first housing 44 and the second housing 68 of the separator 28 are connected to the first end plate via the bolt 98 inserted into the bolt insertion hole 58 from the hole 96 and the nut 100 screwed into the bolt 98. Fastened to 94a.

  The first end plate 94a includes a single fuel gas supply pipe 102 communicating with the fuel gas supply communication hole 30, four oxidant gas supply pipes 104 communicating with the respective oxidant gas supply communication holes 54, and exhaust gas. Four exhaust gas discharge pipes 105 communicating with the passage 88 are provided.

  The support plate 112 is fixed to the first end plate 94 a via a plurality of bolts 98, nuts 108 a and 108 b and a plate-like collar member 110. Between the support plate 112 and the first end plate 94a, a first load applying unit 114 that applies a tightening load to the first fuel gas supply unit 36 and the second fuel gas supply unit 60, and an oxidant gas supply unit 56. A second load applying unit 116 that applies a tightening load to the electrode and a third load applying unit 118 that applies a tightening load to each electrolyte / electrode assembly 26 are provided.

  The first load applying unit 114 is configured to prevent the fuel gas from leaking from the fuel gas supply communication hole 30 (the central part of the first fuel gas supply unit 36 and the second fuel gas supply unit 60). The pressing member 120 is positioned near the center of the arrangement of the four second end plates 94b and presses the fuel cell 10 via the partition wall 95. A first spring 124 is disposed on the pressing member 120 via a first receiving member 122a and a second receiving member 122b. The tip of the first pressing bolt 126 abuts on the second receiving member 122b. The first pressing bolt 126 is screwed into a first screw hole 128 formed in the support plate 112 and is fixed through a first nut 130 so that the position can be adjusted.

  The second load applying unit 116 includes a bolt 98 inserted into the bolt insertion hole 58 from the hole 96 and a nut 100 screwed into the bolt 98, and an oxidant gas is supplied from the oxidant gas supply unit 56. It has a function to prevent leakage.

  The third load applying unit 118 includes a third receiving member 132 a disposed on the second end plate 94 b corresponding to each electrolyte / electrode assembly 26. The third receiving member 132a is positioned and supported by the second end plate 94b via the pins 134. One end of the second spring 136 contacts the third receiving member 132a, while the other end of the second spring 136 contacts the fourth receiving member 132b. The tip of the second pressing bolt 138 contacts the fourth receiving member 132b. The second pressing bolt 138 is screwed into a second screw hole 140 formed in the support plate 112 and is fixed via a second nut 142 so that the position can be adjusted.

  The operation of the fuel cell stack 12 configured as described above will be described below.

  As shown in FIG. 1, the fuel gas is supplied from the fuel gas supply pipe 102 connected to the first end plate 94a to the fuel gas supply communication hole 30, and the oxidant gas is supplied from the oxidant gas supply pipe 104. Air that is an oxygen-containing gas is supplied to the supply unit 56.

  As shown in FIGS. 4 and 7, the fuel gas supplied to the fuel gas supply communication hole 30 moves in the stacking direction (arrow A direction), and the second plate 34 of the separator 28 constituting each fuel cell 10. The fuel gas is supplied to each fuel gas supply passage 74 through a circumferential groove 72 from the groove portion 70 formed in the above. The fuel gas moves along the fuel gas supply passage 74 and is then introduced into the fuel gas passage 46 from the fuel gas supply hole 52 formed in the first plate 32.

  The fuel gas supply hole 52 is provided corresponding to the approximate center position of the anode electrode 24 of each electrolyte / electrode assembly 26. Accordingly, the fuel gas is supplied from the fuel gas supply hole 52 to the anode electrode 24 and flows through the fuel gas passage 46 from the substantially central portion of the anode electrode 24 toward the outer peripheral portion.

  On the other hand, the air supplied to the oxidant gas supply unit 56 is once filled into a filling chamber 76 provided between the first housing unit 44 of the first plate 32 and the second housing unit 68 of the second plate 34. Is done. An oxidant gas supply passage 78 communicates with the filling chamber 76, and the oxidant gas moves along the respective oxidant gas supply passages 78 to the center side of the first sandwiching portion 40 and the second sandwiching portion 64. To do.

  An oxidant gas supply hole 80 communicates in the vicinity of the center of the second sandwiching portion 64, and the oxidant gas supply hole 80 is provided corresponding to a substantially central position of the cathode electrode 22 of the electrolyte / electrode assembly 26. It has been. As a result, as shown in FIG. 7, air is supplied from the oxidant gas supply hole 80 to the cathode electrode 22, and the oxidant formed on the felt member 84 from the substantially central portion of the cathode electrode 22 toward the outer peripheral portion. The gas passage 86 flows.

  Accordingly, in each electrolyte / electrode assembly 26, fuel gas is supplied from the substantially central portion of the anode electrode 24 toward the outer peripheral portion, and air is supplied from the substantially central portion of the cathode electrode 22 toward the outer peripheral portion, Power generation is performed. The fuel gas and air used for power generation are exhausted from the outer periphery of each electrolyte / electrode assembly 26 to the exhaust gas passage 88 as exhaust gas.

  In this case, in the first embodiment, as shown in FIG. 5, the width H2 of the second bridge portion 42 is set larger than the width H1 of the first bridge portion 38, so that the second bridge portion 42 is disconnected. The area is set larger than the cross-sectional area of the first bridge portion 38.

  For this reason, the stress is relieved by the first bridge portion 38 in a state where the tightening load is applied to the fuel cell stack 12 via the first load applying portion 114, the second load applying portion 116, and the third load applying portion 118. be able to.

  That is, the first bridge portion 38 is restrained by the first load applying portion 114 and the third load applying portion 118, and the second bridge portion 42 is fixed by the second load applying portion 116 and the third load applying portion 118. It is restrained. Accordingly, stress is generated in the first bridge portion 38 and the second bridge portion 42 through thermal expansion due to operation of the fuel cell stack 12 and thermal contraction due to operation stop. At that time, since the load per unit area of the cross section of the first bridge portion 38 is set to be larger than the load per unit area of the cross section of the second bridge portion 42, the load is cut off from the second bridge portion 42. Stress is relieved by the first bridge portion 38 having a small area.

  Similarly, as shown in FIG. 6, the load per unit area of the cross section of the short second bridge portion 66 is set to be larger than the load per unit area of the cross section of the long first bridge portion 62. As a result, the stress is relaxed by the first bridge portion 62 having a smaller cross-sectional area than the second bridge portion 66. For this reason, deformation and damage of the separator 28 can be satisfactorily prevented with a simple configuration.

  Moreover, the second bridge portions 42 and 66 can be configured as short as possible, and the entire separator 28 can be easily made compact. As a result, the entire fuel cell stack 12 is shortened as much as possible in the dimension (diameter) along the surface direction of the separator 28, and the entire fuel cell stack 12 can be easily reduced in size.

  Furthermore, the first housing unit 44 and the second housing unit 68 are configured in an annular shape. For this reason, the exhaust heat from the exhaust gas can be evenly transferred to the entire first housing portion 44 and the second housing portion 68. For this reason, the oxidant gas before being supplied to the electrolyte / electrode assembly 26 can be uniformly heated. In addition, since the first casing portion 44 and the second casing portion 68 constitute the outer shape of the separator 28 and have an annular shape, the overall outer dimensions of the fuel cell stack 12 are satisfactorily narrowed, and the fuel cell. The stack can be made compact.

  FIG. 8 is an exploded perspective view of the fuel cell 160 according to the second embodiment of the present invention, and FIG. 9 is a schematic cross-sectional explanatory view for explaining the operation of the fuel cell 160.

  The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the third to sixth embodiments described below, detailed description thereof is omitted.

  The separator 162 constituting the fuel cell 160 includes a first plate 164 and a second plate 166. The first clamping portion 40 constituting the first plate 164 has a flat surface in contact with the electrolyte / electrode assembly 26, and fuel gas is supplied to the surface along the electrode surface of the anode electrode 24. A conductive felt member (conductive non-woven fabric such as metal felt) 167 that forms a fuel gas passage 46 for close contact with the anode electrode 24 is disposed (see FIGS. 8 and 9). In place of the conductive felt member, a mesh member (conductive woven fabric such as a metal mesh), a foam metal, an expanded metal, a punching metal, or a press embossed metal may be employed.

  The second sandwiching portion 64 constituting the second plate 166 is provided with a plurality of protrusions 168 that form the oxidant gas passage 86 on the surface that contacts the cathode electrode 22. The protrusion 168 is formed by etching, for example.

  FIG. 10 is an exploded perspective view of a fuel cell 170 according to a third embodiment of the present invention, and FIG. 11 is a schematic cross-sectional explanatory view for explaining the operation of the fuel cell 170.

  The separator 172 constituting the fuel cell 170 includes a first plate 174 and a second plate 176. A plurality of protrusions 48 that form a fuel gas passage 46 are provided on the surface of the first sandwiching portion 40 that constitutes the first plate 174 in contact with the anode electrode 24. A plurality of protrusions 168 that form an oxidant gas passage 86 are provided on the surface of the second sandwiching portion 64 that constitutes the second plate 176 in contact with the cathode electrode 22.

  As described above, in the second and third embodiments, it is effective that the separators 162 and 172 are deformed or damaged even if stress due to thermal expansion or contraction occurs in the separators 162 and 172. The same effects as those of the first embodiment described above can be obtained.

  The above-described first and second embodiments are combined, and a felt member (conductive non-woven fabric such as metal felt) 84 forming the oxidant gas passage 86 and a felt member (metal felt) forming the fuel gas passage 46 are combined. Or a conductive non-woven fabric such as 167 may be used. Instead of the felt members 84 and 167, a mesh member (conductive woven fabric such as a metal mesh), a foam metal, an expanded metal, a punching metal, or a press embossed metal may be employed.

  FIG. 12 is an exploded perspective view of a fuel cell 180 according to the fourth embodiment of the present invention.

  The separator 182 constituting the fuel cell 180 includes a first plate 184 and a second plate 186. A plurality of, for example, three second bridge portions 188 a, 188 b, and 188 c are integrally provided on the first sandwiching portion 40 and the first housing portion 44 constituting the first plate 184. The second bridge portions 188a, 188b and 188c are configured to be shorter than the first bridge portion 38, and the overall cross-sectional area of the second bridge portions 188a, 188b and 188c is the cross-sectional area of the first bridge portion 38. Is set larger than.

  Second bridge portions 190 a, 190 b, and 190 c are integrally provided on the second sandwiching portion 64 and the second housing portion 68 constituting the second plate 186. The second bridge portions 190a, 190b, and 190c are configured to be shorter than the first bridge portion 62, similar to the second bridge portions 188a, 188b, and 188c, and the second bridge portions 190a, 190b, and The overall cross-sectional area 190c is set larger than the cross-sectional area of the first bridge portion 62.

  In the fourth embodiment configured as described above, the same effects as those of the first to third embodiments can be obtained.

  FIG. 13 is an exploded perspective view of a fuel cell 200 according to the fifth embodiment of the present invention.

  The separator 202 that constitutes the fuel cell 200 includes a first plate 204 and a second plate 206. The first bridge portion 208 and the first housing portion 44 constituting the first plate 204 are integrally provided with a second bridge portion 208. The second bridge 208 extends in a direction crossing a straight line connecting the first bridge 38 from the fuel gas supply communication hole 30. That is, the second bridge portion 208 has a width equivalent to that of the first bridge portion 38 and extends in a direction intersecting with the extending direction of the first bridge portion 38.

  A second bridge portion 210 is integrally provided on the second sandwiching portion 64 and the second housing portion 68 that constitute the second plate 206. Similar to the second bridge portion 208, the second bridge portion 210 has a width equivalent to that of the first bridge portion 62 and extends in a direction intersecting with the extending direction of the first bridge portion 62. Provided.

  In the fifth embodiment configured as described above, the first sandwiching portion 40 and the second sandwiching portion 64 are in the direction of arrow E that is not constrained by the first bridge portions 38 and 62 and the second bridge portions 208 and 210. It is movable. For this reason, the same effects as those of the first to fourth embodiments can be obtained, and the stress generated in the first bridge portions 38 and 62 and the second bridge portions 208 and 210 can be released well. There is an advantage. This is because the extending direction of the first bridge portions 38 and 62 and the extending direction of the second bridge portions 208 and 210 are not linearly arranged.

  FIG. 14 is an exploded perspective view of a fuel cell 220 according to the sixth embodiment of the present invention.

  The separator 222 constituting the fuel cell 220 includes a first plate 224 and a second plate 226. A second bridge portion 228 is integrally provided on the first sandwiching portion 40 and the first housing portion 44 constituting the first plate 224. The second bridge portion 228 has a width equivalent to that of the first bridge portion 38 and is set in a wave shape that can be elastically deformed (see FIG. 15).

  A second bridge portion 230 is integrally provided on the second sandwiching portion 64 and the second housing portion 68 that constitute the second plate 226. Similar to the second bridge portion 228, the second bridge portion 230 has a width equivalent to that of the first bridge portion 62 and is set in a wave shape that can be elastically deformed.

  In 6th Embodiment comprised in this way, the 2nd bridge parts 228 and 230 are set to the wave shape which can be elastically deformed. For this reason, the 2nd bridge parts 228 and 230 itself have spring elasticity (stress relaxation function), and the stress which acts on the 2nd bridge parts 228 and 230 is eased favorably. Accordingly, the same effects as those of the first to fifth embodiments can be obtained, such as making the entire separator 222 compact and effectively preventing deformation of the separator 222.

  In the sixth embodiment, only the second bridge portions 228 and 230 are set in a wave shape. However, the present invention is not limited to this, and the first bridge portions 228 and 230 are replaced with the first bridge portions 228 and 230. Only the bridge portions 38 and 62 may be set in a wave shape, or the first bridge portions 38 and 62 may be set in a wave shape together with the second bridge portions 228 and 230.

1 is a schematic perspective view of a fuel cell stack according to a first embodiment of the present invention in which a plurality of fuel cells are stacked. FIG. FIG. 2 is a cross-sectional view of the fuel cell stack taken along line II-II in FIG. 1. FIG. 3 is an exploded perspective view of the fuel cell. It is a partially exploded perspective view showing the gas flow state of the fuel cell. It is explanatory drawing of the 1st plate which comprises a separator. It is explanatory drawing of the 2nd plate which comprises the said separator. It is a schematic cross-sectional explanatory drawing explaining operation | movement of the said fuel cell. It is a disassembled perspective view of the fuel cell which concerns on the 2nd Embodiment of this invention. It is a schematic cross-sectional explanatory drawing explaining operation | movement of the said fuel cell. It is a disassembled perspective view of the fuel cell which concerns on the 3rd Embodiment of this invention. It is a schematic cross-sectional explanatory drawing explaining operation | movement of the said fuel cell. It is a disassembled perspective view of the fuel cell which concerns on the 4th Embodiment of this invention. It is a disassembled perspective view of the fuel cell which concerns on the 5th Embodiment of this invention. It is a disassembled perspective view of the fuel cell which concerns on the 6th Embodiment of this invention. It is a principal part expansion disassembled perspective view of the said fuel cell. It is explanatory drawing of the separator which comprises the flat laminated fuel cell of patent document 1. FIG.

Explanation of symbols

10, 160, 170, 180, 200, 220 ... Fuel cell 12 ... Fuel cell stack 20 ... Electrolyte 22 ... Cathode electrode 24 ... Anode electrode 26 ... Electrolyte / electrode assembly 28, 162, 172, 182, 202, 222 ... Separator 30 ... Fuel gas supply communication holes 32, 34, 164, 166, 174, 176, 184, 186, 204, 206, 224, 226 ... Plates 36, 60 ... Fuel gas supply units 38, 42, 62, 66, 188a- 188c, 190a to 190c, 208, 210, 228, 230 ... bridge portion 40, 64 ... clamping portion 44, 68 ... housing portion 46 ... fuel gas passage 48, 168 ... projection 52 ... fuel gas supply hole 54 ... oxidant Gas supply communication hole 56... Oxidant gas supply section 74. Fuel gas supply passage 76. Filling chamber 78. Oxidant gas supply holes 84, 167 ... felt members 86 ... oxidant gas passages 88 ... exhaust gas passages 90, 92 ... insulating seals 94a, 94b ... end plates 112 ... support plates 114, 116, 118 ... load applying portions

Claims (8)

A fuel cell stack comprising a fuel cell in which an electrolyte / electrode assembly configured by sandwiching an electrolyte between an anode electrode and a cathode electrode, and a separator, and a plurality of the fuel cells are stacked,
The separator sandwiches the electrolyte / electrode assembly and supplies an oxidant gas along the electrode surface of the cathode electrode and a fuel gas supply hole for supplying fuel gas along the electrode surface of the anode electrode A sandwiching portion provided with an oxidant gas supply hole for
A first bridge portion connected to the sandwiching portion and forming a first reaction gas supply passage for supplying the fuel gas to the fuel gas supply hole or supplying the oxidant gas to the oxidant gas supply hole;
A first reaction gas supply unit that is connected to the first bridge portion and has a first reaction gas supply communication hole formed in the stacking direction for supplying the fuel gas or the oxidant gas to the first reaction gas supply passage. When,
A second bridge portion connected to the sandwiching portion and forming a second reaction gas supply passage for supplying the oxidant gas to the oxidant gas supply hole or the fuel gas to the fuel gas supply hole;
A housing connected to the second bridge and containing the electrolyte / electrode assembly;
A second reactive gas supply unit that is provided in the casing and has a second reactive gas supply communication hole formed in the stacking direction for supplying the oxidant gas or the fuel gas to the second reactive gas supply passage. When,
With
The first bridge part and the second bridge part are set in an asymmetric shape, and the load per unit area of one of the first bridge part and the second bridge part is the other cross section. A fuel cell stack, wherein the fuel cell stack is set to be smaller than the load per unit area. 2. The fuel cell stack according to claim 1, wherein the first bridge portion is restrained by the first reactive gas supply portion and the clamping portion,
The fuel cell stack, wherein the second bridge portion is restrained by the second reactive gas supply unit and the clamping unit.   3. The fuel cell stack according to claim 2, wherein the second bridge portion is configured to be shorter and wider than the first bridge portion. 4.   3. The fuel cell stack according to claim 2, wherein the second bridge portion is configured to be shorter and more numerous than the first bridge portion. A fuel cell stack comprising a fuel cell in which an electrolyte / electrode assembly configured by sandwiching an electrolyte between an anode electrode and a cathode electrode, and a separator, and a plurality of the fuel cells are stacked,
The separator sandwiches the electrolyte / electrode assembly and supplies an oxidant gas along the electrode surface of the cathode electrode and a fuel gas supply hole for supplying fuel gas along the electrode surface of the anode electrode A sandwiching portion provided with an oxidant gas supply hole for
A first bridge portion connected to the sandwiching portion and forming a first reaction gas supply passage for supplying the fuel gas to the fuel gas supply hole or supplying the oxidant gas to the oxidant gas supply hole;
A first reaction gas supply unit that is connected to the first bridge portion and has a first reaction gas supply communication hole formed in the stacking direction for supplying the fuel gas or the oxidant gas to the first reaction gas supply passage. When,
A second bridge portion connected to the sandwiching portion and forming a second reaction gas supply passage for supplying the oxidant gas to the oxidant gas supply hole or the fuel gas to the fuel gas supply hole;
A housing connected to the second bridge and containing the electrolyte / electrode assembly;
A second reactive gas supply unit that is provided in the casing and has a second reactive gas supply communication hole formed in the stacking direction for supplying the oxidant gas or the fuel gas to the second reactive gas supply passage. When,
With
The fuel cell stack, wherein the second bridge portion has a width equivalent to that of the first bridge portion and extends in a direction intersecting with an extending direction of the first bridge portion. A fuel cell stack comprising a fuel cell in which an electrolyte / electrode assembly configured by sandwiching an electrolyte between an anode electrode and a cathode electrode, and a separator, and a plurality of the fuel cells are stacked,
The separator sandwiches the electrolyte / electrode assembly and supplies an oxidant gas along the electrode surface of the cathode electrode and a fuel gas supply hole for supplying fuel gas along the electrode surface of the anode electrode A sandwiching portion provided with an oxidant gas supply hole for
A first bridge portion connected to the sandwiching portion and forming a first reaction gas supply passage for supplying the fuel gas to the fuel gas supply hole or supplying the oxidant gas to the oxidant gas supply hole;
A first reaction gas supply unit that is connected to the first bridge portion and has a first reaction gas supply communication hole formed in the stacking direction for supplying the fuel gas or the oxidant gas to the first reaction gas supply passage. When,
A second bridge portion connected to the sandwiching portion and forming a second reaction gas supply passage for supplying the oxidant gas to the oxidant gas supply hole or the fuel gas to the fuel gas supply hole;
A housing connected to the second bridge and containing the electrolyte / electrode assembly;
A second reactive gas supply unit that is provided in the casing and has a second reactive gas supply communication hole formed in the stacking direction for supplying the oxidant gas or the fuel gas to the second reactive gas supply passage. When,
With
At least the first bridge part or the second bridge part is set in a wave shape that can be elastically deformed. 7. The fuel cell stack according to claim 1, wherein a plurality of the sandwiching portions are connected to a single first reaction gas supply portion via a plurality of the first bridge portions. 8. With
Each sandwiching portion is integrally provided with a single casing portion via each second bridge portion, and a plurality of the second reactive gas supply portions are formed in the casing portion. A fuel cell stack.   8. The fuel cell stack according to claim 7, wherein the casing is configured in an annular shape.

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