JP2014086263A - Fuel cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell module that makes such adjustment as to equalize pressure losses in adjacent reactant gas passages for circulating identical reactant gas and that ensures good power generation performance.SOLUTION: A fuel cell module 10 includes power generation units 12. A fuel gas inlet communication hole 24a and an inlet of a first fuel gas passage 34 communicate with each other through a first inlet side connecting passage 58. The fuel gas inlet communication hole 24a and an inlet of a second fuel gas passage 42 communicate with each other through a second inlet side connecting passage 60. A pressure loss adjustment member 66 is provided in the second inlet side connecting passage 60 that communicates with the inlet of the second fuel gas passage 42.

Description

  The present invention comprises a plurality of electrolyte membrane / electrode structures provided with a pair of electrodes on both sides of the electrolyte membrane, and a plurality of separators, wherein the separators and the electrolyte membrane / electrode structures are alternately laminated, and The present invention also relates to a fuel cell module in which the separator is disposed at both ends in the stacking direction.

  For example, in a polymer electrolyte fuel cell, an electrolyte membrane / electrode structure (MEA) in which an anode electrode and a cathode electrode are disposed on both sides of a solid polymer electrolyte membrane made of a polymer ion exchange membrane is sandwiched between separators. Power generation cells (unit cells). In a fuel cell, several tens to several hundreds of power generation cells are usually stacked and used, for example, as an in-vehicle fuel cell stack.

  In a fuel cell, a so-called internal manifold is often configured to supply a fuel gas and an oxidant gas, which are reaction gases, to the anode electrode and the cathode electrode of each of the stacked power generation cells.

  The internal manifold includes a reaction gas communication hole (a fuel gas communication hole and an oxidant gas communication hole) provided through the power generation cell in the stacking direction and a cooling medium communication hole. The reaction gas communication hole communicates with a reaction gas flow channel (fuel gas flow channel, oxidant gas flow channel) that supplies the reaction gas along the electrode surface, while the cooling medium communication hole extends in the electrode surface direction between the separators. A cooling medium flow path for supplying a cooling medium along the communication path.

  In this case, a so-called thinning cooling structure is employed in which a cooling medium flow path is formed for each of the two or more power generation cells to cool the plurality of power generation cells. This is because the number of separators can be reduced, the configuration is simplified, and the entire fuel cell stack can be reduced in size and simplified.

  As a fuel cell stack of this kind of thinning cooling structure, for example, a fuel cell disclosed in Patent Document 1 is known. As shown in FIG. 14, the fuel cell 1 is configured by stacking a plurality of fuel cells 2. The fuel cell 2 is configured by alternately sandwiching electrode structures 3a and 3b between a plurality of separators 4a, 4b, and 4c. Sealing members 5a and 5b are arranged between the separators 4a and 4b and between the separators 4b and 4c to block the fuel gas passage 6 and the oxidant gas passage (not shown) in a sealed state.

  A connecting passage 8a communicating with the fuel gas supply port 7 is formed between the separators 4a and 4b, and a connecting passage 8b communicating with the fuel gas supply port 7 is provided between the separators 4c and 4a. . In the separators 4b and 4a, through passages 9a and 9b are formed at positions offset from each other in the stacking direction. The connection passage 8a communicates with one fuel gas flow channel 6 through the through passage 9a, and the connection passage 8b communicates with the other fuel gas flow passage 6 through the through passage 9b.

JP 2003-197221 A

  Incidentally, in the fuel cell 1 described above, since the through passages 9a and 9b are offset from each other in the stacking direction, the passage lengths of the connecting passages 8a and 8b from the fuel gas supply port 7 to the respective through passages 9a and 9b. Are different. That is, the connecting passage 8a has a shorter passage length than the connecting passage 8b. On the other hand, the lengths of the passages from the through passages 9a and 9b to the power generation units are also different. In particular, during this time, the cross-sectional area of the passage is small compared to other parts, and the pressure loss is high. For this reason, when the passage length is different, the pressure loss on the through passage 9a side is considerably increased. Thereby, there is a problem that the flow rate of the fuel gas supplied to the electrode structure 3b is relatively reduced, and the power generation performance is deteriorated.

  The present invention solves this type of problem, and it is possible to uniformly adjust the pressure loss of each reaction gas flow channel that circulates the same reaction gas adjacently to ensure good power generation performance. An object of the present invention is to provide a fuel cell module capable of satisfying the requirements.

  The present invention comprises a plurality of electrolyte membrane / electrode structures provided with a pair of electrodes on both sides of the electrolyte membrane, and a plurality of separators, wherein the separators and the electrolyte membrane / electrode structures are alternately laminated, and The present invention relates to a fuel cell module in which the separator is disposed at both ends in the stacking direction.

  In this fuel cell module, a plurality of first reaction gas passages for allowing one reaction gas to flow along one electrode of each electrolyte membrane / electrode structure, and the other reaction gas to each electrolyte membrane / electrode structure And a plurality of second reaction gas flow paths that circulate along the other electrode, and a cooling medium flow path that circulates the cooling medium only between the fuel cell modules is formed.

  A pressure loss adjusting member that adjusts the pressure loss of one of the reaction gases is provided in either the inlet side connection channel that communicates with the inlet of the at least one first reaction gas channel or the outlet side connection channel that communicates with the outlet. Is provided.

  Further, in this fuel cell module, it is preferable that the pressure loss adjusting member is provided only in the inlet side connection channel of at least one first reaction gas channel.

  Furthermore, in this fuel cell module, the separator is provided with a reaction gas inlet communication hole and a reaction gas outlet communication hole that allow one reaction gas to flow through in the stacking direction. The passage communicates with the reaction gas inlet communication hole or the reaction gas outlet communication hole, and communicates with the first passage portion extending in the surface direction of the separator and the first passage portion, and passes through the separator. One inlet-side connection flow path, and a second passage part that communicates with the through-hole part and extends in the surface direction of the separator and communicates with the first reaction gas flow path. Alternatively, the through-hole portion of one of the outlet-side connection channels and the through-hole portion of the other inlet-side connection channel or the other outlet-side connection channel are positioned in the stacking direction. Offset and placed The Kano said first passage portion, it is preferable that the pressure loss adjusting member is provided.

  Furthermore, in this fuel cell module, it is preferable that a pressure loss adjusting member is provided on the separator surface facing the through hole.

  In this fuel cell module, the pressure loss adjusting member is preferably provided integrally with the seal member on the separator surface.

  According to the present invention, the pressure loss at the inlet or outlet of the at least one first reaction gas channel is adjusted. For this reason, the pressure loss in at least one first reaction gas channel can be made uniform with the pressure loss in other first reaction gas channels, and the reaction gas supplied to the plurality of first reaction gas channels can be made uniform. The flow rate is adjusted equally. Therefore, it is possible to uniformly adjust the pressure loss of the first reaction gas flow paths adjacent to each other to allow the same reaction gas to flow, and to ensure good power generation performance.

It is a principal part disassembled perspective explanatory drawing of the electric power generation unit which comprises 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 power generation unit. FIG. 3 is a cross-sectional explanatory view taken along line III-III in FIG. 1 of the power generation unit. It is front explanatory drawing of the 1st metal separator which comprises the said electric power generation unit. It is explanatory drawing of one surface of the 2nd metal separator which comprises the said electric power generation unit. It is explanatory drawing of the other surface of the said 2nd metal separator. It is explanatory drawing of one surface of the 3rd metal separator which comprises the said electric power generation unit. It is explanatory drawing of the other surface of the said 3rd metal separator. FIG. 4 is an explanatory cross-sectional view showing dimensions of a first inlet side connecting channel of a first fuel gas channel and a second inlet side connecting channel of a second fuel gas channel constituting the power generation unit. It is a relation explanatory view of passage height and passage length of the 1st entrance side connection channel and the 2nd entrance side connection channel. It is explanatory drawing of the pressure loss of the said 1st fuel gas flow path and the said 2nd fuel gas flow path. It is a principal part disassembled perspective explanatory drawing of the electric power generation unit which comprises the fuel cell which concerns on the 2nd Embodiment of this invention. It is XIII-XIII line sectional explanatory drawing in FIG. 12 of the said electric power generation unit. 2 is a cross-sectional explanatory view of a fuel cell disclosed in Patent Document 1. FIG.

  As shown in FIGS. 1 to 3, the fuel cell module 10 according to the first embodiment of the present invention includes a power generation unit 12, and the plurality of power generation units 12 are arranged in a horizontal direction (arrow A direction) or a vertical direction ( Are laminated together along the direction of arrow C). The power generation unit 12 includes a first metal separator 14, a first electrolyte membrane / electrode structure (MEA) 16 a, a second metal separator 18, a second electrolyte membrane / electrode structure (MEA) 16 b, and a third metal separator 20. .

  In the first embodiment, the fuel cell module 10 includes two MEAs and three separators, but is not limited thereto. The fuel cell module 10 may include, for example, three MEAs and four separators, or four MEAs and five separators.

  The first metal separator 14, the second metal separator 18, and the third metal separator 20 are, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a horizontally long metal whose surface has been subjected to anticorrosion treatment. Consists of plates. The first metal separator 14, the second metal separator 18, and the third metal separator 20 have a rectangular planar shape, and are formed into a concavo-convex shape by pressing a metal thin plate into a wave shape. In addition, the 1st metal separator 14, the 2nd metal separator 18, and the 3rd metal separator 20 can be comprised by a carbon separator, for example.

  As shown in FIG. 1, specifically, the length of the first metal separator 14, the second metal separator 18, and the third metal separator 20 is arranged at one end edge of the power generation unit 12 in the long side direction (arrow B direction). One end edge in the side direction communicates with each other in the direction of arrow A, and an oxidant gas inlet communication hole 22a for supplying an oxidant gas, for example, an oxygen-containing gas, and a cooling medium inlet for supplying a cooling medium. A communication hole 23a and a fuel gas outlet communication hole 24b for discharging a fuel gas, for example, a hydrogen-containing gas, are provided.

  The other end edge of the power generation unit 12 in the long side direction (arrow B direction) communicates with each other in the direction of arrow A, the fuel gas inlet communication hole 24a for supplying the fuel gas, and the cooling medium for discharging the cooling medium A cooling medium outlet communication hole 23b and an oxidant gas outlet communication hole 22b for discharging the oxidant gas are provided.

  As shown in FIG. 4, the surface 14a of the first metal separator 14 facing the first electrolyte membrane / electrode structure 16a is connected to the oxidant gas inlet communication hole 22a and the oxidant gas outlet communication hole 22b. An oxidant gas flow path (second reaction gas flow path) 26 is formed.

  The first oxidant gas flow channel 26 has a plurality of linear flow channel grooves (or wavy flow channel grooves) 26a extending in the direction of arrow B, and the vicinity of the inlet of the first oxidant gas flow channel 26 and In the vicinity of the outlet, an oxidant gas inlet buffer portion 28a and an oxidant gas outlet buffer portion 28b are provided. The oxidant gas inlet buffer portion 28a and the oxidant gas outlet buffer portion 28b are each configured by a plurality of embosses, but may be configured by a plurality of flow channel grooves, for example. The same applies to each buffer unit described below.

  Between the oxidant gas inlet buffer portion 28a and the oxidant gas inlet communication hole 22a, a plurality of inlet connection grooves 30a constituting a bridge portion are formed, while the oxidant gas outlet buffer portion 28b and the oxidant gas are formed. A plurality of outlet connection grooves 30b constituting a bridge portion are formed between the outlet communication holes 22b. Lid members 31a and 31b are disposed in the inlet connecting groove 30a and the outlet connecting groove 30b.

  As shown in FIG. 1, a part of the cooling medium flow path 32 that connects the cooling medium inlet communication hole 23 a and the cooling medium outlet communication hole 23 b is formed on the surface 14 b of the first metal separator 14. A part of the cooling medium flow channel 32 has a back surface shape of the linear flow channel groove portion 26a and has a plurality of linear flow channel grooves 32a extending in the direction of arrow B. A cooling medium inlet buffer unit 33a and a cooling medium outlet buffer unit 33b are provided in the vicinity of the inlet and the outlet of the cooling medium flow path 32, respectively. The cooling medium inlet buffer unit 33a and the cooling medium outlet buffer unit 33b have the back surface shape of the oxidant gas inlet buffer unit 28a and the oxidant gas outlet buffer unit 28b.

  As shown in FIG. 5, the first fuel gas that communicates the fuel gas inlet communication hole 24a and the fuel gas outlet communication hole 24b with the surface 18a of the second metal separator 18 facing the first electrolyte membrane / electrode structure 16a. A flow path (first reaction gas flow path) 34 is formed. The first fuel gas channel 34 has a plurality of linear channel grooves (which may be wavy channel grooves) 34a extending in the direction of arrow B.

  A fuel gas inlet buffer part 35a and a fuel gas outlet buffer part 35b are provided in the vicinity of the inlet and the outlet of the first fuel gas channel 34, respectively. A plurality of supply holes (through holes) 36a are formed in the vicinity of the fuel gas inlet communication hole 24a, and a plurality of discharge holes (through holes) 36b in the vicinity of the fuel gas outlet communication hole 24b. Is formed.

  As shown in FIG. 6, the surface 18b of the second metal separator 18 facing the second electrolyte membrane / electrode structure 16b is connected to the oxidant gas inlet communication hole 22a and the oxidant gas outlet communication hole 22b. An oxidant gas flow path (second reaction gas flow path) 38 is formed. The second oxidant gas flow path 38 has a plurality of linear flow path grooves (or wavy flow path grooves) 38a extending in the direction of arrow B.

  An oxidant gas inlet buffer part 39a and an oxidant gas outlet buffer part 39b are provided in the vicinity of the inlet and the outlet of the second oxidant gas flow path 38, respectively. The oxidant gas inlet buffer part 39a and the oxidant gas outlet buffer part 39b have the back surface shape of the fuel gas outlet buffer part 35b and the fuel gas inlet buffer part 35a.

  Between the oxidant gas inlet buffer part 39a and the oxidant gas inlet communication hole 22a, a plurality of inlet connection grooves 40a constituting a bridge part are formed, while the oxidant gas outlet buffer part 39b and the oxidant gas are formed. A plurality of outlet connection grooves 40b constituting a bridge portion are formed between the outlet communication holes 22b. Lid members 41a and 41b are disposed in the inlet connecting groove 40a and the outlet connecting groove 40b.

  As shown in FIG. 7, the second fuel gas flow communicating with the fuel gas inlet communication hole 24a and the fuel gas outlet communication hole 24b is formed on the surface 20a of the third metal separator 20 facing the second electrolyte membrane / electrode structure 16b. A channel (first reaction gas channel) 42 is formed. The second fuel gas channel 42 has a plurality of linear channel grooves (which may be wave-shaped channels) 42a extending in the direction of arrow B. A fuel gas inlet buffer 43a and a fuel gas outlet buffer 43b are provided in the vicinity of the inlet and the outlet of the second fuel gas channel 42, respectively.

  A plurality of supply holes (through holes) 44a are formed in the vicinity of the fuel gas inlet communication hole 24a, and a plurality of discharge holes (through holes) 44b are formed in the vicinity of the fuel gas outlet communication hole 24b. Is formed. As shown in FIG. 2, the supply hole 44a is disposed on the inner side (fuel gas flow path side) of the supply hole 36a of the second metal separator 18, while the discharge hole 44b is formed as shown in FIG. The second metal separator 18 is disposed on the inner side (fuel gas flow path side) than the discharge hole portion 36b.

  As shown in FIG. 8, a part of the cooling medium flow path 32 that is the back surface shape of the second fuel gas flow path 42 is formed on the surface 20 b of the third metal separator 20. A part of the cooling medium flow channel 32 has a back surface shape of the linear flow channel groove portion 42a and has a plurality of linear flow channel grooves 32b extending in the direction of arrow B.

  A cooling medium inlet buffer 45a and a cooling medium outlet buffer 45b are provided in the vicinity of the inlet and the outlet of the cooling medium flow path 32, respectively. The cooling medium outlet buffer unit 45b and the cooling medium inlet buffer unit 45a have the back surface shape of the fuel gas inlet buffer unit 43a and the fuel gas outlet buffer unit 43b.

  As shown in FIG. 1, the power generation units 12 are stacked on each other, so that the first metal separator 14 that constitutes one power generation unit 12 and the third metal separator 20 that constitutes the other power generation unit 12. The cooling medium flow path 32 is formed.

  A first seal member 46 is integrally formed on the surfaces 14 a and 14 b of the first metal separator 14 around the outer peripheral edge of the first metal separator 14. A second seal member 48 is integrally formed on the surfaces 18a and 18b of the second metal separator 18 around the outer peripheral edge of the second metal separator 18, and the surfaces 20a and 20b of the third metal separator 20 are integrally formed. The third seal member 50 is integrally formed around the outer peripheral edge of the third metal separator 20.

  Examples of the first seal member 46, the second seal member 48, and the third seal member 50 include EPDM, NBR, fluororubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene, or acrylic rubber. A sealing material having elasticity such as a sealing material, a cushioning material, or a packing material is used.

  As shown in FIG. 4, the first seal member 46 includes an oxidant gas inlet communication hole 22 a, an oxidant gas outlet communication hole 22 b, and a first oxidant gas flow path 26 on the surface 14 a of the first metal separator 14. It has the 1st convex-shaped seal part 46a which connects outer periphery.

  As shown in FIG. 5, the second seal member 48 surrounds the supply hole portion 36 a and the discharge hole portion 36 b and the first fuel gas flow path 34 on the surface 18 a of the second metal separator 18 so as to communicate with each other. It has the 1st convex-shaped seal part 48a.

  As shown in FIG. 6, the second seal member 48 has a second surface 18b that communicates the outer periphery of the oxidant gas inlet communication hole 22a, the oxidant gas outlet communication hole 22b, and the second oxidant gas flow path 38. A convex seal portion 48b is provided.

  As shown in FIG. 7, the third seal member 50 surrounds and communicates the supply hole portion 44 a and the discharge hole portion 44 b with the second fuel gas channel 42 on the surface 20 a of the third metal separator 20. It has the 1st convex-shaped seal part 50a.

  As shown in FIG. 8, the third seal member 50 communicates the outer periphery of the cooling medium inlet communication hole 23 a, the cooling medium outlet communication hole 23 b, and the cooling medium flow path 32 on the surface 20 b of the third metal separator 20. Two convex seal portions 50b are provided.

  As shown in FIG. 2, the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b include, for example, a solid polymer electrolyte membrane 52 in which a perfluorosulfonic acid thin film is impregnated with water, A cathode electrode 54 and an anode electrode 56 sandwiching the solid polymer electrolyte membrane 52 are provided. The solid polymer electrolyte membrane 52 has a larger planar dimension (surface area) than the planar dimension (surface area) of the cathode electrode 54 and the anode electrode 56. The first electrolyte membrane / electrode structure 16a is set to have a larger planar dimension than the second electrolyte membrane / electrode structure 16b.

  The cathode electrode 54 and the anode electrode 56 are formed by uniformly applying gas diffusion layers 54a and 56a made of carbon paper or the like and porous carbon particles carrying a platinum alloy on the surface thereof to the surfaces of the gas diffusion layers 54a and 56a. Electrode catalyst layers 54b and 56b. The electrode catalyst layers 54 b and 56 b are formed on both surfaces of the solid polymer electrolyte membrane 52. In the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b, the respective power generation regions are set in the same region (see FIG. 1).

  As shown in FIG. 2, the fuel gas inlet communication hole 24 a and the inlet of the first fuel gas channel 34 communicate with each other through a first inlet side connection channel 58. The fuel gas inlet communication hole 24 a communicates with the inlet of the second fuel gas channel 42 through the second inlet side connection channel 60. As shown in FIG. 3, the fuel gas outlet communication hole 24 b and the outlet of the first fuel gas channel 34 communicate with each other through a first outlet side connecting channel 62. The fuel gas outlet communication hole 24 b communicates with the outlet of the second fuel gas flow path 42 through the second outlet side connection flow path 64.

  As shown in FIG. 2, the first inlet side connection channel 58 communicates with the fuel gas inlet communication hole 24 a, and the separator surface direction (arrow B direction) between the second metal separator 18 and the third metal separator 20. A first passage portion 58a extending to the first passage portion 58a, a supply hole portion 36a communicating with the first passage portion 58a, and a communication hole communicating with the supply hole portion 36a, and the second metal separator 18 and the first electrolyte membrane / electrode structure. And a second passage portion 58b extending in the separator surface direction and communicating with the first fuel gas passage 34.

  The second inlet side connection flow path 60 communicates with the fuel gas inlet communication hole 24a, and extends in the separator surface direction between the third metal separator 20 and the first metal separator 14 of the power generation unit 12 adjacent thereto. A passage portion 60a, a supply hole portion 44a communicating with the first passage portion 60a, and a separator between the third metal separator 20 and the second electrolyte membrane / electrode structure 16b, communicating with the supply hole portion 44a. A second passage portion 60b extending in the surface direction and communicating with the second fuel gas passage 42.

  In the first embodiment, a pressure loss adjusting member 66 that adjusts the pressure loss of the fuel gas is provided in the second inlet side connection flow channel 60 that communicates with the inlet of the second fuel gas flow channel 42. The pressure loss adjusting member 66 is provided integrally with the first seal member 46 on the separator surface facing the supply hole 44 a in the first passage portion 60 a, that is, on the surface 14 b of the first metal separator 14. The pressure loss adjusting member 66 extends from the vicinity of the fuel gas inlet communication hole 24a to a position covering the supply hole 44a. The pressure loss adjusting member 66 may be made of a material different from that of the first seal member 46.

  As shown in FIG. 3, the first outlet side connection channel 62 communicates with the fuel gas outlet communication hole 24 b, and the separator surface direction (arrow B direction) between the second metal separator 18 and the third metal separator 20. A first passage portion 62a extending to the first passage portion, a discharge hole portion 36b communicating with the first passage portion 62a, and a communication member communicating with the discharge hole portion 36b, and the second metal separator 18 and the first electrolyte membrane / electrode structure. And a second passage portion 62b extending in the separator surface direction and communicating with the first fuel gas passage 34.

  The second outlet side connection channel 64 communicates with the fuel gas outlet communication hole 24b, and extends in the separator surface direction between the third metal separator 20 and the first metal separator 14 of the power generation unit 12 adjacent thereto. A passage portion 64a, a discharge hole portion 44b communicating with the first passage portion 64a, and a separator between the third metal separator 20 and the second electrolyte membrane / electrode structure 16b, communicating with the discharge hole portion 44b. A second passage portion 64b extending in the surface direction and communicating with the second fuel gas passage 42.

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

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 22a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 24a. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 23a.

  For this reason, as shown in FIG. 4, the oxidant gas flows from the oxidant gas inlet communication hole 22a through the inlet connection groove 30a and the oxidant gas inlet buffer portion 28a to the first oxidant gas flow of the first metal separator 14. Supplied to the channel 26. Further, as shown in FIG. 6, the oxidant gas passes through the oxidant gas inlet communication hole 22a, the inlet connection groove 40a and the oxidant gas inlet buffer 39a, and the second oxidant gas flow path of the second metal separator 18. 38.

  As shown in FIGS. 1, 4 and 6, the oxidant gas moves in the direction of arrow B (horizontal direction) along the first oxidant gas flow path 26, and the first electrolyte membrane / electrode structure 16a. In addition to being supplied to the cathode electrode 54, it moves in the direction of arrow B along the second oxidant gas flow path 38 and is supplied to the cathode electrode 54 of the second electrolyte membrane / electrode structure 16 b.

  On the other hand, as shown in FIGS. 2 and 5, the fuel gas is supplied from the fuel gas inlet communication hole 24a through the supply hole 36a of the second metal separator 18 to the fuel gas inlet buffer 35a. The fuel gas is supplied to the first fuel gas flow path 34 of the second metal separator 18 through the fuel gas inlet buffer portion 35a.

  The fuel gas is supplied from the fuel gas inlet communication hole 24a through the supply hole 44a of the third metal separator 20 to the fuel gas inlet buffer 43a as shown in FIGS. The fuel gas is supplied to the second fuel gas channel 42 of the third metal separator 20 through the fuel gas inlet buffer 43a.

  As shown in FIGS. 1, 5 and 7, the fuel gas moves in the direction of arrow B along the first fuel gas flow path 34 and is supplied to the anode electrode 56 of the first electrolyte membrane / electrode structure 16a. At the same time, it moves in the direction of arrow B along the second fuel gas flow path 42 and is supplied to the anode electrode 56 of the second electrolyte membrane / electrode structure 16b.

  Therefore, in the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b, the oxidant gas supplied to each cathode electrode 54 and the fuel gas supplied to each anode electrode 56 are electrodes. Electricity is generated by being consumed by an electrochemical reaction in the catalyst layers 54b and 56b.

  Next, as shown in FIGS. 4 and 6, the oxidant gas supplied to and consumed by the cathode electrodes 54 of the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b becomes an oxidant. The gas outlet buffer portions 28b and 39b are discharged into the oxidant gas outlet communication hole 22b.

  The fuel gas consumed by being supplied to the anode electrode 56 of the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b is, as shown in FIGS. 5 and 7, the fuel gas outlet buffer 35b. , 43b. As shown in FIG. 3, the fuel gas is discharged to the fuel gas outlet communication hole 24b through the discharge holes 36b and 44b.

  On the other hand, the cooling medium supplied to the pair of left and right cooling medium inlet communication holes 23a is introduced into the cooling medium flow path 32 as shown in FIG. The cooling medium moves in the direction of arrow B to cool the first electrolyte membrane / electrode structure 16a and the second electrolyte membrane / electrode structure 16b. This cooling medium is discharged to the cooling medium outlet communication hole 23b.

  In this case, as shown in FIG. 9, the first inlet-side connecting flow path 58 that connects the fuel gas inlet communication hole 24a and the inlet (power generation unit end) of the first fuel gas flow path 34 has a passage length L1. A first passage portion 58a having a supply hole portion 36a and a second passage portion 58b having a passage length L2 are provided. Here, passage length L1 + passage length L2 = total passage length L0.

  On the other hand, the second inlet side connection flow path 60 that communicates the fuel gas inlet communication hole 24a and the inlet (power generation part end) of the second fuel gas flow path 42 has a first passage part 60a having a passage length L3, A second passage portion 60b having a supply hole portion 44a and a passage length L4 is provided. Here, passage length L3 + passage length L4 = total passage length L0.

  The supply hole 36a and the supply hole 44a are offset in the arrow B direction with respect to the stacking direction (arrow A direction). For this reason, the relationship of passage length L1 <passage length L3 and passage length L4 <passage length L2 is set. Accordingly, the second passage portions 58b and 60b have a small cross-sectional area, so that the pressure loss of the second passage portion 58b is higher than the pressure loss of the second passage portion 60b.

  Therefore, in the first embodiment, a pressure loss adjusting member 66 that adjusts the pressure loss of the fuel gas is provided in the first passage portion 60a. That is, the passage height b of the first passage portion 60a is set to be smaller than the passage height a of the first passage portion 58a (passage height a> passage height b). The second passage portions 58b and 60b are set to a small passage height c. Each passage height a, b, and c has the relationship shown in FIG.

  Thereby, the cross-sectional area of the first passage portion 60a is set smaller than the cross-sectional area of the first passage portion 58a, and the pressure loss of the first passage portion 60a is adjusted to be larger than the pressure loss of the first passage portion 58a. The For this reason, as shown in FIG. 11, the pressure loss of the entire first fuel gas passage 34 is adjusted to be equal to the pressure loss of the entire second fuel gas passage 42.

  Accordingly, the pressure loss in the first fuel gas flow channel 34 can be made uniform with the pressure loss in the second fuel gas flow channel 42, and is supplied to the first fuel gas flow channel 34 and the second fuel gas flow channel 42. The fuel gas flow rate is adjusted equally. Thereby, the pressure loss of the 1st fuel gas flow path 34 and the 2nd fuel gas flow path 42 which distribute | circulate the same fuel gas adjacently can be adjusted uniformly, and it can ensure favorable electric power generation performance. The effect of becoming.

  Furthermore, in the first embodiment, the pressure loss adjusting member 66 is provided on the surface 14b of the first metal separator 14 so as to face the supply hole 44a in the first passage 60a. For this reason, a level | step difference is not formed in the 1st channel | path part 60a, but fuel gas can be distribute | circulated smoothly along the said 1st channel | path part 60a.

  Moreover, the pressure loss adjusting member 66 is provided integrally with the first seal member 46. Therefore, the manufacturing operation of the pressure loss adjusting member 66 is effectively simplified. Further, by providing the pressure loss adjusting member 66, it is possible to prevent water from being introduced into the first passage portion 60a from the fuel gas inlet communication hole 24a.

  Further, the first outlet side connecting channel 62 and the second outlet side connecting channel 64 are not provided with the pressure loss adjusting member 66. Accordingly, passage blockage due to swelling, deterioration, or peeling of the pressure loss adjusting member 66 due to discharged water can be effectively avoided.

  In the first embodiment, the second inlet side connecting flow path 60 includes the pressure loss adjusting member 66 that adjusts the pressure loss of the fuel gas. However, the second inlet side connecting flow path 60 is provided as necessary. Instead of this, the pressure loss adjusting member 66 may be provided in the second outlet side connection channel 64.

  FIG. 12 is an exploded perspective view of the main part of the power generation unit 82 constituting the fuel cell module 80 according to the second embodiment of the present invention. Note that the same components as those of the fuel cell module 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The fuel cell module 80 is configured by stacking a plurality of power generation units 82. In the power generation unit 82, a pressure loss adjusting member 84 is provided on the surface 20b of the third metal separator 20 between the inlet of the second fuel gas passage 42 and the fuel gas inlet communication hole 24a.

  As shown in FIG. 13, the pressure loss adjusting member 84 is disposed in the second inlet side connecting flow path 60 that communicates with the inlet of the second fuel gas flow path 42. For example, the pressure loss adjusting member 84 is provided integrally with the third seal member 50, but may be formed of a material different from that of the third seal member 50.

  In the second embodiment configured as described above, the pressure loss adjustment for adjusting the pressure loss of the fuel gas in the first passage portion 60a of the second inlet side connection flow path 60 communicating with the inlet of the second fuel gas flow path 42 is performed. A member 84 is provided. For this reason, the pressure loss of the first passage portion 60a is adjusted to be larger than the pressure loss of the first passage portion 58a, and the pressure loss of the first fuel gas passage 34 and the second fuel gas passage 42 can be adjusted uniformly. Thus, the same effects as those of the first embodiment can be obtained, such as ensuring good power generation performance.

  In the first and second embodiments, the pressure loss adjusting members 66 and 84 are provided in the first passage portion 60a of the second inlet side connection flow path 60 communicating with the inlet of the second fuel gas flow path 42. Yes. Instead of this, or in addition to this, in order to adjust the pressure loss at the inlet or outlet of either the first oxidant gas flow channel 26 or the second oxidant gas flow channel 38, a pressure loss adjusting member (FIG. (Not shown) may be provided.

  Further, in the first oxidant gas flow channel 26 and the second oxidant gas flow channel 38, supply holes 36a and 44a and discharge holes provided in the first fuel gas flow channel 34 and the second fuel gas flow channel 42 are provided. A configuration in which the portions 36b and 44b are provided can be employed. At that time, the pressure loss adjusting member 66 or the pressure loss adjusting member 84 can be disposed at the inlet of the first oxidant gas flow channel 26 or the second oxidant gas flow channel 38.

DESCRIPTION OF SYMBOLS 10, 80 ... Fuel cell module 12, 82 ... Electric power generation unit 14, 18, 20 ... Metal separator 16a, 16b ... Electrolyte membrane and electrode structure 22a ... Oxidant gas inlet communication hole 22b ... Oxidant gas outlet communication hole 23a ... Cooling Medium inlet communication hole 23b ... Cooling medium outlet communication hole 24a ... Fuel gas inlet communication hole 24b ... Fuel gas outlet communication hole 26, 38 ... Oxidant gas flow path 32 ... Cooling medium flow path 34, 42 ... Fuel gas flow path 36a, 44a ... Supply hole 36b, 44b ... Discharge hole 46, 48, 50 ... Sealing member 52 ... Solid polymer electrolyte membrane 54 ... Cathode electrode 56 ... Anode electrode 58, 60 ... Inlet side connection flow path 58a, 58b, 60a, 60b ... passage portions 62, 64 ... outlet side connecting flow channels 66, 84 ... pressure loss adjusting member

Claims (5)

A plurality of electrolyte membrane / electrode structures each having a pair of electrodes provided on both sides of the electrolyte membrane, and a plurality of separators, wherein the separators and the electrolyte membrane / electrode structures are alternately stacked, and both ends in the stacking direction A fuel cell module in which the separator is disposed,
A plurality of first reaction gas flow paths for allowing one reaction gas to flow along one electrode of each electrolyte membrane / electrode structure;
A plurality of second reaction gas flow paths for allowing the other reaction gas to flow along the other electrode of each electrolyte membrane / electrode structure;
And a cooling medium flow path for circulating the cooling medium only between the fuel cell modules is formed,
A pressure loss adjusting member that adjusts the pressure loss of the one reaction gas is provided in either one of the inlet side connection channel that communicates with the inlet of the at least one first reaction gas channel or the outlet side connection channel that communicates with the outlet. A fuel cell module provided.   2. The fuel cell module according to claim 1, wherein the pressure loss adjusting member is provided only in the inlet-side connection channel of at least one of the first reaction gas channels. The fuel cell module according to claim 1 or 2, wherein the separator is provided with a reaction gas inlet communication hole and a reaction gas outlet communication hole through which the one reaction gas flows in the stacking direction,
The inlet-side connection channel or the outlet-side connection channel communicates with the reaction gas inlet communication hole or the reaction gas outlet communication hole and extends in the surface direction of the separator;
A through-hole portion communicating with the first passage portion and penetrating the separator;
A second passage portion that communicates with the through-hole portion, extends in the surface direction of the separator, and communicates with the first reaction gas flow path;
And having
The through-hole portion of one of the inlet-side connection channels or one of the outlet-side connection channels and the other through-hole portion of the inlet-side connection channel or the other outlet-side connection channel are laminated. Each position is offset relative to the direction,
In any one of the first passage portions, the pressure loss adjusting member is provided.   4. The fuel cell module according to claim 3, wherein the pressure loss adjusting member is provided on a separator surface facing the through-hole portion.   5. The fuel cell module according to claim 3, wherein the pressure loss adjusting member is provided integrally with a seal member on the separator surface. 6.

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