Fuel cell system

Abstract

The present invention relates to a fuel cell system. The auxiliary equipment housing (64) of the fuel cell system (10) sequentially has a first layer (84), a second layer (86), and a third layer (88) from the end panel side. A refrigerant discharge pipe (96) is disposed in the first layer (84). The cathode discharge pipe (90) has: a plurality of first through portions (91), each of the plurality of first through portions is connected to a plurality of oxidant gas lead-out through holes (76b) sandwiching the refrigerant discharge pipe (96) and penetrates the first layer (84) in the thickness direction; and a first communication portion (92) which is provided in the second layer (86), extends in the layer direction of the second layer (86) so as to straddle the outside of the refrigerant discharge pipe (96), and communicates the plurality of first through portions (91).

Description

Technical Field

[0001] The present invention relates to a fuel cell system. Background Art

[0002] A fuel cell system has a fuel cell stack formed by stacking a plurality of power generation single cells, and the power generation single cells generate power as fuel gas and oxidant gas are supplied thereto. In addition, the fuel cell system further includes auxiliary equipment for adjusting the fuel gas and oxidant gas supplied to the fuel cell stack, and piping for supplying a refrigerant to the fuel cell stack. In order to compactly arrange these auxiliary equipment and piping, an auxiliary equipment housing is provided adjacent to an end plate at one end of the fuel cell stack, and the piping and a part of the auxiliary equipment are housed in the auxiliary equipment housing.

[0003] In a conventional fuel cell system, inside the auxiliary equipment housing, auxiliary equipment such as an ejector and a humidifier is housed together with piping for supplying and discharging fuel gas, oxidant gas, and refrigerant. In this case, sometimes a part of the piping also forms a block-shaped piping member in which a bent flow path is formed integrally (for example, Patent Document 1).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-053234 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] However, in a fuel cell system, it is necessary to arrange piping while avoiding large-sized structures such as a humidifier and an ejector in a limited internal space of the auxiliary equipment housing. Therefore, in the block-shaped piping, the degree of freedom in arrangement is small, and when it is desired to avoid interference with large-sized structures, it sometimes leads to an increase in size.

[0009] Accordingly, an object of the present invention is to provide a fuel cell system capable of compactly arranging piping members while avoiding interference with large-sized structures.

[0010] Means for Solving the Problems

[0011] The fuel cell system of one embodiment disclosed below includes: a fuel cell stack having a pair of end plates; a plurality of through-holes formed through a plurality of portions of one of the end plates to allow fuel gas, oxidant gas, and refrigerant to pass through; an auxiliary equipment housing disposed adjacent to the end plate having the through-holes; a cathode discharge pipe connected to the through-holes to allow the oxidant discharge gas discharged from the fuel cell stack to flow; and a refrigerant discharge pipe connected to the through-holes to allow the refrigerant discharged from the fuel cell stack to flow. The auxiliary equipment housing has: a layered first layer closest to the end plate; a layered second layer disposed outside the first layer; and a third layer disposed outside the second layer. The refrigerant discharge pipe is disposed within the first layer. The cathode discharge pipe has: a plurality of first through portions respectively connected to the plurality of through-holes sandwiching the refrigerant discharge pipe and penetrating the first layer in the thickness direction; and a first communication portion disposed in the second layer and extending along the layer direction of the second layer so as to straddle the outside of the refrigerant discharge pipe and communicating the plurality of first through portions.

[0012] Effects of the Invention

[0013] According to the fuel cell system of the above embodiment, it is possible to appropriately arrange piping components while avoiding interference with large-sized structures.

[0014] The following embodiments will be described with reference to the drawings, and the above objects, features, and advantages can be easily understood from the description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an exploded perspective view showing the fuel cell system according to the embodiment.

[0016] Figure 2 It shows Figure 1 the exploded perspective view of the structure of the power generation single cell.

[0017] Figure 3 It is an explanatory view showing the layer structure inside the auxiliary equipment housing.

[0018] Figure 4 It is a front view showing the arrangement of the refrigerant discharge pipe, the cathode discharge pipe, and the humidifier in the auxiliary equipment housing.

[0019] Figure 5 It is along Figure 4 the V-V line of to show the explanatory view of the arrangement of the first layer.

[0020] Figure 6 It is along Figure 4The explanatory drawing showing the configuration of the second layer is shown by the VI-VI line.

[0021] Figure 7 The explanatory drawing showing the configuration of the third layer. Detailed Description of the Invention

[0022] Hereinafter, preferred embodiments of the present invention will be given and described in detail with reference to the accompanying drawings.

[0023] As Figure 1 shown, a fuel cell system 10 according to an embodiment of the present invention includes a fuel cell stack 11 having a plurality of power generation single cells 12. The power generation single cells 12 generate power as fuel gas and oxidant gas are supplied, and the temperature is adjusted as refrigerant is supplied. The fuel cell system 10 includes a stack housing 14, and the plurality of power generation single cells 12 are housed inside the stack housing 14 in a stacked state. The fuel cell system 10 is mounted, for example, in a motor room of a fuel cell vehicle (not shown).

[0024] In a state where the fuel cell system 10 is mounted on a fuel cell vehicle, the plurality of power generation single cells 12 are stacked in a standing posture with the electrode surface along the vehicle width direction (arrow symbol B direction) orthogonal to the vehicle length direction (arrow symbol A direction), and are configured as a stacked body 16. Further, the plurality of power generation single cells 12 may be stacked along the gravity direction (arrow symbol C direction).

[0025] In addition, at both ends in the stacking direction (arrow symbol B direction) of the stacked body 16, a wiring board (not shown) and an insulating member are arranged in order outward. The wiring board is a metal plate member that extracts power from the power generation single cell 12, and causes a power extraction terminal (not shown) to protrude from a predetermined position of the stacked body 16. The insulating member is formed of an insulating material such as polycarbonate (PC) or phenolic resin, for example.

[0026] As Figure 2 shown, the resin-framed MEA 24 of the power generation single cell 12 is sandwiched between two separators (hereinafter, also referred to as "first separator 26" and "second separator 28" respectively). The first and second separators 26 and 28 are formed by stamping the cross section of a thin metal plate such as a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a metal surface of which a surface treatment for corrosion prevention has been performed into a waveform. The outer peripheries of the first separator 26 and the second separator 28 are joined to each other by welding, brazing, caulking (Japanese: かしめ), etc., and are configured as an integrated joined separator.

[0027] The MEA 24 with a resin frame includes: an electrolyte membrane - electrode structure 30 (hereinafter referred to as "MEA 30"); and a resin frame member 32 that is joined to the outer peripheral portion of the MEA 30 and surrounds the outer peripheral portion. The MEA 30 has an electrolyte membrane 34, an anode electrode 36 provided on one surface of the electrolyte membrane 34, and a cathode electrode 38 provided on the other surface of the electrolyte membrane 34. Moreover, it is also possible that the MEA 30 does not use the resin frame member 32 and the electrolyte membrane 34 protrudes outward. Additionally, frame - shaped resin films can be provided on both sides of the electrolyte membrane 34 that protrudes outward.

[0028] The electrolyte membrane 34 can be, for example, a solid polymer electrolyte membrane (cation - exchange membrane) that is a thin film containing water - containing perfluorosulfonic acid. Moreover, in addition to fluorine - based electrolytes, the electrolyte membrane 34 can also use HC (hydrocarbon) - based electrolytes.

[0029] On the surface 26a of the first separator 26 facing the cathode electrode 38 of the MEA 24 with a resin frame, there is provided an oxidant gas flow path 40 (in Figure 2 for the sake of convenience, the flow direction of the oxidant gas is shown on the cathode electrode 38 of the MEA 30). The oxidant gas flow path 40 is constituted by a linear flow path groove or a wavy flow path groove formed between a plurality of convex portions extending along the arrow symbol A direction (horizontal direction) on the first separator 26.

[0030] On the surface 28a of the second separator 28 facing the anode electrode 36 of the MEA 24 with a resin frame, there is provided a fuel gas flow path 42. The fuel gas flow path 42 is constituted by a linear flow path groove or a wavy flow path groove formed between a plurality of convex portions extending along the arrow symbol A direction on the second separator 28.

[0031] Between the surface 26b of the first separator 26 and the surface 28b of the second separator 28 that are joined to each other, there is provided a refrigerant flow path 44. The refrigerant flow path 44 is formed by the coincidence of the back shape of the first separator 26 where the oxidant gas flow path 40 is formed and the back shape of the second separator 28 where the fuel gas flow path 42 is formed.

[0032] In addition, on both side portions (arrow symbol Ar side and arrow symbol Af side) in the long - side direction of the power - generating single cell 12, that is, in the arrow symbol A direction, there are provided a plurality of communication holes 46 that enable the oxidant gas, the fuel gas, and the refrigerant to flow independently along the stacking direction of the power - generating single cell 12.

[0033] A plurality of communication holes 46 provided on the side of the arrow symbol Ar (rear of the fuel cell system 10) include an oxidant gas inlet communication hole 48a as a second communication hole, two fuel gas outlet communication holes 50b as first communication holes, and two refrigerant inlet communication holes 52a as third communication holes. The communication holes 46 are arranged substantially along the vertical direction. The oxidant gas inlet communication hole 48a, the two refrigerant inlet communication holes 52a, and the two fuel gas outlet communication holes 50b penetrate the power generation single cell 12 in the stacking direction.

[0034] The oxidant gas inlet communication hole 48a is formed at the middle position of the five communication holes 46 arranged along the arrow symbol C direction. The two refrigerant inlet communication holes 52a are formed at positions adjacent to the oxidant gas inlet communication hole 48a vertically above and below, and the oxidant gas inlet communication hole 48a is sandwiched between the two refrigerant inlet communication holes 52a. The two fuel gas outlet communication holes 50b are arranged at positions above the upper refrigerant inlet communication hole 52a and below the lower refrigerant inlet communication hole 52a, and the oxidant gas inlet communication hole 48a and the two refrigerant inlet communication holes 52a are sandwiched between the two fuel gas outlet communication holes 50b.

[0035] A plurality of communication holes 46 provided on the side of the arrow symbol Af (front of the fuel cell system 10) include two oxidant gas outlet communication holes 48b as second communication holes, a fuel gas inlet communication hole 50a as a first communication hole, and two refrigerant outlet communication holes 52b as third communication holes. The communication holes 46 are arranged substantially along the arrow symbol C direction. The two oxidant gas outlet communication holes 48b, the fuel gas inlet communication hole 50a, and the two refrigerant outlet communication holes 52b penetrate the power generation single cell 12 in the stacking direction.

[0036] The fuel gas inlet communication hole 50a is formed at the middle position of the five communication holes 46 arranged along the arrow symbol C direction. The two refrigerant outlet communication holes 52 are formed at positions adjacent to the fuel gas inlet communication hole 50a vertically above and below, and the fuel gas inlet communication hole 50a is sandwiched between the two refrigerant outlet communication holes 52. The two oxidant gas outlet communication holes 48b are arranged at positions above the upper refrigerant outlet communication hole 52b and below the lower refrigerant outlet communication hole 52b, and the fuel gas inlet communication hole 50a and the two refrigerant outlet communication holes 52 are sandwiched between the two oxidant gas outlet communication holes 48b.

[0037] In addition, in the present embodiment, the oxidant gas inlet communication hole 48a and the fuel gas inlet communication hole 50a are not particularly limited and may be formed, for example, in a hexagonal shape. Further, it is also possible that the flow path cross-sectional area of the fuel gas inlet communication hole 50a is smaller than that of the oxidant gas inlet communication hole 48a. On the other hand, the oxidant gas outlet communication hole 48b, the fuel gas outlet communication hole 50b, the refrigerant inlet communication hole 52a, and the refrigerant outlet communication hole 52b are not particularly limited and may be formed, for example, in a triangular shape.

[0038] The oxidant gas flow path 40 is in fluid communication with the oxidant gas inlet communication hole 48a and the two oxidant gas outlet communication holes 48b. The oxidant gas is supplied from the oxidant gas inlet communication hole 48a to the oxidant gas flow path 40, whereby the oxidant gas flow path 40 causes the oxidant gas to flow along the direction of the arrow symbol A and discharges the oxidant gas to the two oxidant gas outlet communication holes 48b. The two oxidant gas outlet communication holes 48b are arranged such that, for example, one side (the base) of the triangular shape faces the oxidant gas flow path 40.

[0039] The fuel gas flow path 42 is in fluid communication with the fuel gas inlet communication hole 50a and the two fuel gas outlet communication holes 50b. The fuel gas is supplied from the fuel gas inlet communication hole 50a to the fuel gas flow path 42, whereby the fuel gas flow path 42 causes the fuel gas to flow along the direction of the arrow symbol A (the direction opposite to that of the oxidant gas) and discharges the fuel gas to the two fuel gas outlet communication holes 50b. The two fuel gas outlet communication holes 50b are arranged such that, for example, one side (the base) of the triangular shape faces the fuel gas flow path 42.

[0040] The refrigerant flow path 44 is in fluid communication with the two refrigerant inlet communication holes 52a and the two refrigerant outlet communication holes 52b. The refrigerant is supplied from the two refrigerant inlet communication holes 52a to the refrigerant flow path 44, whereby the refrigerant flow path 44 causes the refrigerant to flow along the direction of the arrow symbol A (the same direction as the fuel gas) and discharges the refrigerant to the two refrigerant outlet communication holes 52b. The two refrigerant inlet communication holes 52a and the two refrigerant outlet communication holes 52b are arranged such that, for example, one apex of the triangular shape faces the refrigerant flow path 44 together.

[0041] Moreover, the arrangement positions, numbers, and shapes of the oxidant gas communication holes 48 (the oxidant gas inlet communication hole 48a and the oxidant gas outlet communication hole 48b), the fuel gas communication holes 50 (the fuel gas inlet communication hole 50a and the fuel gas outlet communication hole 50b), and the refrigerant communication holes 52 (the refrigerant inlet communication hole 52a and the refrigerant outlet communication hole 52b) are not limited to those described above. Each communication hole 46 may be appropriately designed according to the required specifications.

[0042] On the surfaces of the first and second separators 26 and 28, a plurality of metal projection seals (sealing members 54) are integrally formed, for example, by stamping, toward the MEA 24 with a resin frame. Instead of the metal projection seals, the sealing member 54 may also be a convex elastic seal formed of an elastic material.

[0043] In addition, a first drainage path 56 is provided in the power generation single cell 12. The first drainage path 56 discharges the generated water produced on the cathode electrode 38 side during the operation (power generation) of the fuel cell system 10. The first drainage path 56 is formed to penetrate the position where the first and second separators 26 and 28 and the resin frame member 32 overlap. The first drainage path 56 communicates with the oxidant gas outlet communication hole 48b via an unillustrated first connection flow path provided at the end (for example, an insulator) of the laminate 16.

[0044] Furthermore, a second drainage path 58 is provided in the power generation single cell 12. The second drainage path 58 discharges the generated water produced on the anode electrode 36 side during the operation (power generation) of the fuel cell system 10. The second drainage path 58 is formed to penetrate the position where the first and second separators 26 and 28 and the resin frame member 32 overlap. The second drainage path 58 communicates with the fuel gas outlet communication hole 50b via an unillustrated second connection flow path provided at the end (for example, an insulator) of the laminate 16.

[0045] Return Figure 1 The stack housing 14 that houses a plurality of power generation single cells 12 has wall portions 18 that extend in a planar shape and cover the entire surface on the front surface, upper surface, and bottom surface. On the other hand, the rear surface and the left and right side surfaces of the stack housing 14 are formed as a window frame 20 (frame shape) having windows 20a that communicate with the internal space 14a of the stack housing 14.

[0046] A wiring board and an insulating board (not shown) provided on one end side (arrow symbol Br side) in the stacking direction of the laminate 16 are housed in the stack housing 14 together with the power generation single cell 12. A side wall 60 that closes the window 20a of the stack housing 14 is attached to one end side of the stack housing 14 in the direction of the arrow symbol B with a sealing member 61 interposed therebetween. The side wall 60 constitutes one end face plate that applies a fastening load in the stacking direction of the power generation single cells 12. Also, a rear wall 62 that closes the window 20a is attached to the rear surface of the stack housing 14 with a sealing member 61 interposed therebetween.

[0047] A wiring board and an insulating board (not shown) provided on the other end side (arrow symbol Bl side) in the stacking direction of the laminate 16 are housed in the stack housing 14 together with the power generation single cell 12. Moreover, an auxiliary equipment housing 64 is attached to the side surface of the stack housing 14 on the other end side in the stacking direction of the power generation single cells 12 so as to close the window 20a with a sealing member 61 interposed therebetween.

[0048] The auxiliary equipment housing 64 is a protective housing for housing and protecting piping and auxiliary equipment components, and is fixed in the horizontal direction of the stack housing 14. As Figure 3 shown, the piping and auxiliary equipment components include the auxiliary equipment 66 (device) of the fuel cell system 10 and the piping 67, through which fuel gas, oxidant gas, and refrigerant, which are fluids, flow. The auxiliary equipment housing 64 has a concave first housing member 68 that is screwed to the stack housing 14 and a concave second housing member 70 that engages with the first housing member 68, and a storage space 64a for housing the piping and auxiliary equipment components is formed inside these members.

[0049] The first housing member 68 has a mounting wall portion 72 that is bolted to the stack housing 14 and divides the internal space 14a of the stack housing 14 from the storage space 64a of the auxiliary equipment housing 64. The mounting wall portion 72 functions as an end panel that applies a fastening load in the stacking direction to the stack 16 of the power generation single cells 12.

[0050] Return Figure 1 , the mounting wall portion 72 has a plurality of through holes 74 that communicate with the plurality of communication holes 46 (oxidant gas communication hole 48, fuel gas communication hole 50, refrigerant communication hole 52) of the power generation single cell 12, respectively. Moreover, it may be that a pair of long holes extending in the vertical direction are provided on the arrow symbol Ar side and the arrow symbol Af side of the mounting wall portion 72, and the pipes corresponding to the respective communication holes 46 penetrate through the pair of long holes and protrude from the piping and auxiliary equipment components described later.

[0051] A plurality of through holes 74 are formed through the mounting wall portion 72 in the thickness direction. Each through hole 74 includes an oxidant gas introduction through hole 76a that communicates with the oxidant gas inlet communication hole 48a, two oxidant gas discharge through holes 76b that communicate with the two oxidant gas outlet communication holes 48b, respectively, a fuel gas introduction through hole 78a that communicates with the fuel gas inlet communication hole 50a, two fuel gas discharge through holes 78b that communicate with the two fuel gas outlet communication holes 50b, respectively, two refrigerant introduction through holes 80a that communicate with the two refrigerant inlet communication holes 52a, respectively, and two refrigerant discharge through holes 80b that communicate with the two refrigerant outlet communication holes 52b, respectively. In addition, although not shown in the figure, a gasket is installed on the inner wall of the through hole 74, and the gasket is configured as follows: it is formed in a perfect circle shape on the outer side (arrow symbol Bl side) and gradually changes to a shape corresponding to the shape of each communication hole 46 toward the inner side (arrow symbol Br side). In addition, it may be a structure in which the shape of the inner wall of the through hole 74 itself gradually changes.

[0052] As Figure 3As shown, in the storage space 64a of the auxiliary equipment housing 64, auxiliary equipment 66 including the fuel cell system 10, piping 67, and auxiliary equipment components are stored. This storage space 64a is successively divided into a first layer 84, a second layer 86, and a third layer 88 from the fuel cell stack 11 toward the outside (in the direction of arrow symbol Bl).

[0053] As Figure 3 shown, the first layer 84 is provided at a position closest to the mounting wall portion 72 of the first housing member 68. The first layer 84 is a layered region parallel to the surface direction of the adjacent mounting wall portion 72 (end panel). The first layer 84 is a region within the range from the mounting wall portion 72 to the inside (excluding the first communication portion 92) compared to the first communication portion 92 of the cathode discharge pipe 90 described later. The second layer 86 is a layered region adjacent to the arrow symbol Bl side (outside) of the first layer 84. The second layer 86 is a region including the first communication portion 92 and within the range from the inside (excluding the humidifier 94) compared to the humidifier 94. The third layer 88 is a layered region adjacent to the arrow symbol Bl side (outside) of the second layer 86. The third layer 88 is a region within the range from the humidifier 94 to the inner end face 70a of the second housing member 70.

[0054] As Figure 5 shown, on the arrow symbol Af side of the first layer 84, a first through portion 91 of the cathode discharge pipe 90, a refrigerant discharge pipe 96, and a fuel gas supply pipe 98 are provided. In addition, on the arrow symbol Ar side of the first layer 84, a second through portion 101 of the anode discharge pipe 100, a refrigerant supply pipe 104, a cathode supply pipe 106, and a part of the gas-liquid separator 108 for fuel discharge gas are provided.

[0055] Two first through portions 91 of the cathode discharge pipe 90 are provided and are respectively connected to the oxidant gas lead-out through holes 76b (refer to Figure 1 ). One first through portion 91 is disposed near the end on the arrow symbol Cu side (upper side in the installation state), and the other first through portion 91 is provided near the end on the arrow symbol Cd side (lower side in the installation state). These first through portions 91 are arranged so as to sandwich the refrigerant discharge pipe 96 from the arrow symbol C direction (vertical direction in the installation state). Each first through portion 91 extends in the direction perpendicular to the main surface of the mounting wall portion 72 (thickness direction of the first layer 84) and penetrates the first layer 84 in the thickness direction.

[0056] Two refrigerant discharge pipes 96 are provided. The two refrigerant discharge pipes 96 are arranged adjacent to both sides of the fuel gas supply pipe 98 in the direction of the arrow symbol C. Each refrigerant discharge pipe 96 has a vertical portion 96a extending in a direction perpendicular to the mounting wall portion 72, and an in-layer pipe portion 96b that bends from the vertical portion 96a and extends along the in-layer direction. When viewed from the direction of the arrow symbol C, the refrigerant discharge pipe 96 is bent in an L shape. The vertical portions 96a are respectively connected to the refrigerant introduction through-holes 80a. The in-layer pipe portion 96b extends in the direction of the arrow symbol Af and penetrates the first housing member 68. A hose (not shown) for guiding the refrigerant to the radiator is connected to the front end of the in-layer pipe portion 96b.

[0057] One fuel gas supply pipe 98 is provided near the center in the direction of the arrow symbol C. The fuel gas supply pipe 98 extends in a direction perpendicular to the main surface of the mounting wall portion 72 (the thickness direction of the first layer 84) in the first layer 84 and penetrates the first layer 84 in the thickness direction.

[0058] Two second through-holes 101 of the anode discharge pipe 100 are provided and are respectively connected to the fuel gas discharge through-holes 78b (see Figure 1 ). The two second through-holes 101 are respectively provided near the ends on the Cu side (the upper side in the set state) and the Cd side (the lower side in the set state) in the direction of the arrow symbol C. The second through-hole 101 extends in a direction perpendicular to the main surface of the mounting wall portion 72 (the thickness direction of the first layer 84) and penetrates the first layer 84 in the thickness direction.

[0059] Two refrigerant supply pipes 104 are provided. The two refrigerant supply pipes 104 are arranged adjacent to both sides of the cathode supply pipe 106 in the direction of the arrow symbol C. In the first layer 84, the refrigerant supply pipe 104 extends in the thickness direction of the first layer 84 and penetrates the first layer 84 in the thickness direction.

[0060] The gas-liquid separator 108 is a box-shaped member and is arranged in the first layer 84 and the second layer 86 as Figure 6 shown. As Figure 5 shown, the gas-liquid separator 108 is adjacently arranged to the second through-hole 101 on the Cd side of the arrow symbol, which is on the lower side in the set state. Inside the gas-liquid separator 108, there is a flow path 108a that is bent to separate moisture in the fuel discharge gas.

[0061] As Figure 6 shown, in the second layer 86, there are arranged the first communication portion 92 of the cathode discharge pipe 90, the fuel gas supply pipe 98, the second communication portion 102 of the anode discharge pipe 100, the third communication portion 110 of the refrigerant supply pipe 104, the third through-hole 112, the cathode supply pipe 106, the gas-liquid separator 108, and the injector 114.

[0062] In the second layer 86, the first communication portion 92 extends in the direction of the arrow C along the in-layer direction of the second layer 86 (the direction parallel to the main surface of the mounting wall portion 72). The first communication portion 92 is configured to connect the first through-hole portion 91 on the Cd side of the arrow with the first through-hole portion 91 on the Cu side of the arrow across the outside of the refrigerant discharge pipe 96. The first through-hole portion 91 on the Cu side (the upper side in the set state) extends in a direction perpendicular to the layer direction of the second layer 86 and penetrates the second layer 86 in the thickness direction.

[0063] The fuel gas supply pipe 98 is bent in the second layer 86 in a manner along the in-layer direction and is connected to the injector 114. The anode discharge pipe 100 has a second communication portion 102 in the second layer 86 that connects the two second through-hole portions 101. One end of the second communication portion 102 is connected to the second through-hole portion 101 on the Cu side of the arrow. The second communication portion 102 extends obliquely in a manner bypassing the cathode supply pipe 106, and the other end of the second communication portion 102 is connected to the inlet 108b of the gas-liquid separator 108. A liquid discharge portion 108c is provided at the end on the Cd side of the arrow of the gas-liquid separator 108, and the liquid discharge portion 108c communicates with the second through-hole portion 101 on the Cd side of the arrow. That is, the second communication portion 102 connects the two second through-hole portions 101 via the gas-liquid separator 108. The second through-hole portion 101 on the Cd side of the arrow extends in a direction perpendicular to the layer direction of the second layer 86 and penetrates the second layer 86 in the thickness direction. The fluid containing a large amount of liquid phase separated by the gas-liquid separator 108 is discharged through the second through-hole portion 101 on the Cd side of the arrow.

[0064] A gas phase outlet 108d is provided on the Cu side of the arrow of the gas-liquid separator 108. The fuel gas of the gas phase component from which the liquid phase component has been removed from the fuel discharge gas flows out from the gas phase outlet 108d. The gas phase outlet 108d is connected to the communication pipe 116 extending along the second layer 86. The communication pipe 116 is connected to the circulation interface 114a of the injector 114 via the check valve 118. The fuel gas from the gas phase outlet 108d is introduced into the fuel gas supply pipe 98 via the injector 114. The injector 114 is connected to a fuel gas pipe (not shown) and is introduced with the fuel gas from the fuel gas supply system.

[0065] Two refrigerant supply pipes 104 are connected by a third communication part 110 provided on the second layer 86. The third communication part 110 extends in the direction of arrow symbol C along the in-layer direction of the second layer 86. As shown in the illustrated example, the third communication part 110 is bent so as to bypass the cathode supply pipe 106. The third through part 112 extends from the third communication part 110 in a direction perpendicular to the second layer 86. The third through part 112 communicates with the third communication part 110 and extends to the third layer 88.

[0066] The cathode supply pipe 106 extends in a direction perpendicular to the second layer 86 and penetrates the second layer 86 in the thickness direction.

[0067] As Figure 7 shown, a humidifier 94, a sealing valve 120, and an exhaust pipe confluence part 122 are mainly arranged on the third layer 88. The humidifier 94 is arranged on the upper side (arrow symbol Cu side) in the close arrangement state on the third layer 88. As Figure 4 shown, the humidifier 94 has a cylindrical casing 94a. As Figure 7 shown, the casing 94a is arranged with its central axis along the third layer 88 and in the same orientation as the arrow symbol A direction.

[0068] Inside the casing 94a of the humidifier 94, there are provided a cylindrical hollow fiber module 94b and a central hole 94c extending along the central axis of the hollow fiber module 94b. The hollow fiber module 94b has a plurality of hollow fibers. In the hollow fiber module 94b, moisture exchange takes place between the fluid flowing in the outer space of the hollow fibers communicating with the central hole 94c and the fluid flowing in the inner space of the hollow fibers.

[0069] The inner space of each hollow fiber of the hollow fiber module 94b communicates with a first inlet interface 124 on the arrow symbol Af side and a first outlet interface 126 on the arrow symbol Ar side. The first inlet interface 124 is connected to an oxidant gas introduction pipe 125. The oxidant gas introduction pipe 125 constitutes a flow path for introducing the oxidant gas supplied from an unillustrated air pump into the first inlet interface 124. The first outlet interface 126 is connected to the cathode supply pipe 106. The first outlet interface 126 of the humidifier 94 is arranged at a position overlapping with the oxidant gas introduction through hole 76a when viewed from a direction perpendicular to the layer direction.

[0070] The central hole 94c communicates with the outer space of the hollow fibers. The central hole 94c becomes a second inlet interface 128 opening to the arrow symbol Af side. The second inlet interface 128 of the central hole 94c is connected to the first through part 91 of the cathode discharge pipe 90. The end of the central hole 94c of the humidifier 94 is arranged at a position overlapping with one of the first through parts 91 (oxidant gas export through hole 76b) when viewed from a direction perpendicular to the layer direction.

[0071] A second outlet interface 130 is provided on the side of the casing 94a on the side of the arrow symbol Cd. The second outlet interface 130 serves as an outlet for the oxidant exhaust gas flowing through the outer space of the hollow fiber. At the second outlet interface 130 of the casing 94a, a sealing valve 120 is installed so as to extend in the direction of the arrow symbol Cd. As Figure 4 shown, the sealing valve 120 is arranged in the direction along the inner direction of the third layer 88. As Figure 7 shown, the sealing valve 120 is arranged in parallel with the first communication portion 92. The sealing valve 120 includes a shut-off valve capable of blocking the flow of the oxidant exhaust gas from the cathode exhaust pipe 90. One end of an exhaust pipe confluence portion 122 is connected to the outlet of the sealing valve 120.

[0072] The exhaust pipe confluence portion 122 is formed to extend along the layer direction of the third layer 88. The exhaust pipe confluence portion 122 is formed in a Y shape when viewed from a direction perpendicular to the layer direction. The first branch pipe 122a is connected to the outlet of the sealing valve 120, and the second branch pipe 122b is connected to the second through portion 101 on the side of the arrow symbol Cd of the anode exhaust pipe 100. The first branch pipe 122a and the second branch pipe 122b merge at the confluence portion 122c. An exhaust port 122d is provided on the side of the arrow symbol Cd of the confluence portion 122c. The exhaust port 122d penetrates the lower end portion (the end portion in the direction of the arrow symbol Cd) of the auxiliary equipment housing 64 and extends to the outside.

[0073] The fuel cell system 10 of the present embodiment is configured as described above, and its operation will be described below.

[0074] In the fuel cell system 10, the fuel gas is supplied to the fuel gas supply pipe 98 under the drive of the injector 114 as Figure 6 shown. The fuel gas in the fuel gas supply pipe 98 flows into the fuel gas inlet communication hole 50a through the fuel gas introduction through hole 78a as Figure 1 shown. Figure 2 shown.

[0075] In addition, the fuel exhaust gas (anode exhaust) flows out from the two fuel gas outlet communication holes 50b. The fuel exhaust gas is discharged to the anode exhaust pipe 100 of the first layer 84 through the two fuel gas discharge through holes 78b as Figure 1 shown. Figure 5 shown. As Figure 6As shown, the fuel exhaust gas in the anode exhaust pipe 100 is separated into a liquid phase component and a gas phase component in the gas-liquid separator 108 of the second layer 86. The separated gas phase component is refluxed to the fuel gas supply pipe 98 through the ejector 114. The fuel exhaust gas containing a large amount of liquid phase component in the gas-liquid separator 108 passes through the second through-hole 101 on the Cd arrow side and is discharged to the exhaust pipe confluence part 122 of the third layer 88.

[0076] The oxidant gas flows in from Figure 7 the oxidant gas inlet pipe 125 of, is humidified by the humidifier 94, and is introduced into the cathode supply pipe 106. The oxidant gas in the cathode supply pipe 106 flows into Figure 1 the oxidant gas inlet through-hole 76a of Figure 2 the oxidant gas inlet communication hole 48a shown in

[0077] The oxidant exhaust gas (cathode exhaust) flows out from the two oxidant gas outlet communication holes 48b. The oxidant exhaust gas is discharged to Figure 1 the first through-hole 91 of the cathode exhaust pipe 90 of the first layer 84 shown in Figure 5 through the two oxidant gas outlet through-holes 76b shown in. The oxidant exhaust gas in the first through-hole 91 merges through the first connection part 92 of the second layer 86 and is introduced into Figure 7 the second inlet interface 128 of the humidifier 94 of the third layer 88 shown in

[0078] The oxidant exhaust gas introduced into the humidifier 94 humidifies the oxidant gas flowing in through the hollow fiber module 94b and is then discharged to the exhaust pipe confluence part 122 through the seal valve 120.

[0079] The oxidant exhaust gas and the fuel exhaust gas merge at Figure 7 the exhaust pipe confluence part 122 of and are discharged from the exhaust port 122d of the auxiliary equipment housing 64.

[0080] Hereinafter, the technical idea and effects of the present invention that can be grasped according to the above-described embodiment will be described.

[0081] The fuel cell system 10 includes: a fuel cell stack 11 having a pair of end plates (for example, side wall 60 and mounting wall portion 72); a plurality of through holes formed through a plurality of portions of one end plate (for example, mounting wall portion 72) through which fuel gas, oxidant gas, and refrigerant pass; an auxiliary equipment housing 64 adjacently provided to the end plate in which the through holes are formed; a cathode discharge pipe 90 connected to a through hole (for example, oxidant gas outlet through hole 76b) and allowing the oxidant discharge gas discharged from the fuel cell stack 11 to flow therethrough; and a refrigerant discharge pipe 96 connected to a through hole (for example, refrigerant outlet through hole 80b) and allowing the refrigerant discharged from the fuel cell stack 11 to flow therethrough. The auxiliary equipment housing 64 has: a layered first layer 84 closest to the end plate (for example, mounting wall portion 72); a layered second layer 86 provided outside the first layer 84; and a third layer 88 provided outside the second layer 86. The refrigerant discharge pipe 96 is disposed within the first layer 84. The cathode discharge pipe 90 has: a plurality of first through portions 91 respectively connected to a plurality of through holes (for example, oxidant gas outlet through holes 76b) sandwiching the refrigerant discharge pipe 96 and penetrating the first layer 84 in the thickness direction; and a first communication portion 92 provided in the second layer 86 and extending along the layer direction of the second layer 86 so as to straddle the outside of the refrigerant discharge pipe 96 and communicating the plurality of first through portions 91.

[0082] According to the above structure, the cathode discharge pipe 90 can be efficiently disposed inside the auxiliary equipment housing 64 while avoiding interference with the refrigerant discharge pipe 96.

[0083] In the above fuel cell system 10, it may also be that a humidifier 94 is further included. The humidifier 94 is disposed in the third layer 88 and is used to humidify the oxidant gas supplied to the fuel cell system 10. Any one of the first through portions 91 of the cathode discharge pipe 90 penetrates the second layer 86 in the thickness direction and is connected to the humidifier 94. According to this structure, the cathode discharge pipe 90 can be connected to the humidifier 94 through the shortest path, and the cathode discharge pipe 90 can be efficiently disposed inside the auxiliary equipment housing 64.

[0084] In the above fuel cell system 10, it may also be that the humidifier 94 has a cylindrical casing 94a, and the axis of the casing 94a is along the in-layer direction of the third layer 88. The first through portion 91 is connected to one end of the casing 94a of the humidifier 94 in the axial direction. In this case, it may also be that the humidifier 94 is disposed near the upper side (arrow symbol Cu side) in the set state. According to this structure, the space in the third layer 88 where pipes and the like can be disposed can be increased.

[0085] In the above-described fuel cell system 10, it is also possible to further include a sealing valve 120. The sealing valve 120 is connected to the second outlet interface 130 of the humidifier 94 and blocks the flow of the oxidant exhaust gas flowing out from the humidifier 94. The sealing valve 120 is arranged in the third layer 88 along the in-layer direction and protrudes parallel to the first communication part 92 from the humidifier 94. According to this structure, the sealing valve 120 can be arranged in the free space of the third layer 88, so that the utilization efficiency of the storage space 64a can be improved.

[0086] In the above-described fuel cell system 10, it is also possible to further include an anode exhaust pipe 100. The anode exhaust pipe 100 is connected to a through-hole (for example, the fuel gas outlet through-hole 78b) and allows the fuel exhaust gas discharged from the fuel cell stack 11 to flow through. The anode exhaust pipe 100 has: a plurality of second through-holes 101, each of the plurality of second through-holes 101 is connected to a plurality of through-holes (for example, the fuel gas outlet through-hole 78b) and penetrates the first layer 84 in the thickness direction; and a second communication part 102, which is arranged in the second layer 86, extends along the layer direction of the second layer 86, and connects the plurality of second through-holes 101. According to this structure, the second communication part 102 of the anode exhaust pipe 100 can be arranged in the second layer 86 together with the first communication part 92 of the cathode exhaust pipe 90, and the compactness can be achieved in the thickness direction perpendicular to the layer.

[0087] In the above-described fuel cell system 10, it is also possible to further include an exhaust pipe confluence part 122. The exhaust pipe confluence part 122 is arranged in the third layer 88 to merge the oxidant exhaust gas flowing out from the sealing valve 120 and the fuel exhaust gas discharged from the anode exhaust pipe 100. Any one of the second through-holes 101 of the anode exhaust pipe 100 penetrates the second layer 86 in the thickness direction and is connected to the exhaust pipe confluence part 122. According to this structure, the exhaust pipe confluence part 122 can be arranged in the free space of the humidifier 94 in the third layer 88, so that the idle space can be effectively utilized and the piping structure can be compacted.

[0088] In the above-described fuel cell system 10, it is also possible to arrange a gas-liquid separator 108 in the second communication part 102. The gas-liquid separator 108 is arranged along the in-layer direction of the second layer 86 and is used to separate the moisture in the fuel exhaust gas. According to this structure, the idle space of the second layer 86 can be effectively utilized and the piping structure can be compacted.

[0089] In the above fuel cell system 10, it is also possible that, in the set state, the humidifier 94 is disposed at a position above the third layer 88 in the vertical direction, the sealing valve 120 and the exhaust pipe merging portion 122 are disposed below the humidifier 94 on the third layer 88, and the discharge port of the exhaust pipe merging portion 122 is provided at the lower end portion of the auxiliary equipment housing 64. According to this structure, when discharging the generated water from the exhaust pipe merging portion 122, it can be discharged by means of gravity, so there is no need to increase the exhaust pressure of the discharged gas more than necessary, and the efficiency of the fuel cell system 10 can be improved.

[0090] In the above content, the preferred embodiments of the present invention are described by way of example, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

Claims

1. A fuel cell system, in which the fuel cell system includes: A fuel cell stack having a pair of end plates; A plurality of through holes that penetrate through a plurality of portions formed in one of the end plates to allow fuel gas, oxidant gas, and refrigerant to pass through; An auxiliary equipment housing that is adjacently disposed to the end plate in which the through holes are formed; A cathode discharge pipe that is connected to the through hole to allow the oxidant discharge gas discharged from the fuel cell stack to flow through; And A refrigerant discharge pipe that is connected to the through hole to allow the refrigerant discharged from the fuel cell stack to flow through, The auxiliary equipment housing has: a layered first layer that is closest to the end plate; a layered second layer that is disposed outside the first layer; and a third layer that is disposed outside the second layer, The refrigerant discharge pipe is disposed within the first layer, The cathode discharge pipe has: two first through portions that are respectively connected to two of the through holes that discharge the oxidant gas and are disposed at positions sandwiching the refrigerant discharge pipe, and penetrate through the first layer in the thickness direction; and a first communication portion that is disposed in the second layer and extends along the layer direction of the second layer and along the arrangement direction of the two through holes that discharge the oxidant gas so as to straddle the outside of the refrigerant discharge pipe and connect the plurality of first through portions, A humidifier is provided in the third layer to humidify the supplied oxidant gas, Any one of the first through portions of the cathode discharge pipe penetrates through the second layer in the thickness direction and is connected to the humidifier.

2. The fuel cell system according to claim 1, wherein The humidifier has a cylindrical casing, and the axis of the casing is along the in-layer direction of the third layer, The first through portion is connected to one end in the axial direction of the casing of the humidifier.

3. The fuel cell system according to claim 2, wherein A shut-off valve is further provided, which is connected to the second outlet interface of the humidifier and blocks the flow of the oxidant discharge gas flowing out of the humidifier, The shut-off valve is disposed in the third layer along the in-layer direction and protrudes parallel to the first communication portion from the humidifier.

4. The fuel cell system according to claim 3, wherein An anode discharge pipe is further provided, which is connected to the through hole to allow the fuel discharge gas discharged from the fuel cell stack to flow through, The anode discharge pipe has: a plurality of second through portions that are respectively connected to the plurality of through holes and penetrate through the first layer in the thickness direction; and a second communication portion that is disposed in the second layer and extends along the layer direction of the second layer to connect the plurality of second through portions.

5. The fuel cell system according to claim 4, wherein It also has an exhaust pipe confluence part which is arranged on the third layer to make the oxidant exhaust gas flowing out from the sealing valve and the fuel exhaust gas discharged from the anode discharge pipe confluence. Any one of the second through parts of the anode discharge pipe penetrates the second layer in the thickness direction and is connected to the exhaust pipe confluence part.

6. The fuel cell system according to claim 4 or 5, characterized in that A gas-liquid separator is provided in the second communication part, and the gas-liquid separator is arranged along the in-layer direction of the second layer to separate moisture in the fuel exhaust gas.

7. The fuel cell system according to claim 5, characterized in that In the set state, the humidifier is arranged in the third layer at a position on the upper side in the vertical direction, and the sealing valve and the exhaust pipe confluence part are arranged in the third layer below the humidifier. An outlet of the exhaust pipe confluence part is provided at the lower end of the auxiliary equipment housing.

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