Fuel cell system

Abstract

The present invention relates to a fuel cell system. A first through hole (118) for inserting a first power extraction member (170a) and a second through hole (120) for inserting a second power extraction member (170b) are formed on an upper wall portion (94d) of a stack casing (90) of the fuel cell system (10). A length (L3) of the second through hole (120) along a stacking direction of a plurality of power generation cells (21) is greater than a length (L4) of the first through hole (118) along the stacking direction.

Description

Technical Field

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

[0002] The fuel cell system includes a stack member and a stack case for accommodating the stack member. The stack member includes a single cell stack, a first wiring member, and a second wiring member. The single cell stack is formed by stacking a plurality of power generation cells. The first wiring member and the second wiring member are provided at both ends of the stacking direction of the plurality of power generation cells in the single cell stack.

[0003] The first wiring member is electrically connected to the electric device unit provided on the upper part of the stack case via the first power lead-out member. The second wiring member is electrically connected to the electric device unit via the second power lead-out member.

[0004] For example, as disclosed in Patent Document 1, a first through hole through which a first power extraction member is inserted and a second through hole through which a second power extraction member is inserted are formed on an upper wall portion of a stack housing. A distance between the second through hole and the second wiring member is smaller than a distance between the first through hole and the second wiring member.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-175719 Summary of the invention

[0008] However, a stack member is formed by laminating a first wiring member, a plurality of power generating cells, and a second wiring member in a stack case, for example. In this case, a compressive load is applied to the stack member from the second wiring member toward the first wiring member.

[0009] In this case, the position of the second wiring member relative to the first wiring member in the stacking direction is deviated due to the assembly tolerance of the plurality of power generating cells and the dimensional tolerance of each power generating cell. That is, the second power lead-out member and the second through hole are easily offset in the stacking direction. Therefore, it is sometimes impossible to reliably insert the second power lead-out member into the second through hole. In addition, when the lengths of the first through hole and the second through hole in the stacking direction are set to be large in advance, there is a problem that the rigidity of the upper wall portion is reduced.

[0010] The object of the present invention is to solve the above-mentioned problems.

[0011] A fuel cell system according to one aspect of the present invention comprises: a stack component having a cell stack formed by stacking a plurality of power generation cells on each other, and a first wiring component and a second wiring component arranged at both ends of the cell stack; and a stack shell which accommodates the stack component, wherein the fuel cell system comprises: a first power extraction component electrically connected to the first wiring component; and a second power extraction component electrically connected to the second wiring component, and an upper wall portion of the stack shell comprises: a first through hole for inserting the first power extraction component; and a second through hole for inserting the second power extraction component, wherein a length of the second through hole along the stacking direction of the plurality of power generation cells is greater than a length of the first through hole along the stacking direction.

[0012] According to the present invention, since the length of the second through hole along the stacking direction is greater than the length of the first through hole along the stacking direction, the positional deviation between the second power lead-out member and the second through hole in the stacking direction can be absorbed by the second through hole. Thus, even when the second wiring member is positionally offset relative to the first wiring member in the stacking direction, the second power lead-out member can be reliably inserted into the second through hole. In addition, since the length of the first through hole along the stacking direction does not exceed the required length, the rigidity of the stack case can be suppressed from being reduced.

[0013] The following embodiments will be described with reference to the accompanying drawings, and the above-mentioned objects, features, and advantages will be easily understood based on the description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a longitudinal sectional view of a fuel cell system according to one embodiment of the present invention.

[0015] Figure 2 It is along Figure 1 Cross-sectional view along line II-II.

[0016] Figure 3 It is along Figure 1 A partially omitted cross-sectional view of line III-III.

[0017] Figure 4 yes Figure 1 An exploded perspective view of a single cell stack.

[0018] Figure 5 It is along Figure 4 A cross-sectional view of line VV.

[0019] Figure 6 Viewed from the second partition member side Figure 4 A top view of the joined bulkhead.

[0020] Figure 7 Observed from above Figure 1 An overhead illustration of the shell structure.

[0021] Figure 8 yes Figure 1 An enlarged sectional explanatory diagram of a first power lead-out member and a second power lead-out member.

[0022] Fig. 9 yes Figure 1 An explanatory diagram of a method for manufacturing a fuel cell system.

[0023] Fig.10 It is an explanatory diagram of the positional deviation between the second power taking-out member and the second through hole. DETAILED DESCRIPTION

[0024] Figure 1 The fuel cell system 10 shown is installed in, for example, a fuel cell electric vehicle (fuel cell vehicle) not shown. Figures 1 to 3 In the figure, the fuel cell system 10 includes a fuel cell stack 12 , fuel cell auxiliary equipment 14 , and an electric device unit 16 .

[0025] The fuel cell stack 12 includes: a stack member 18; and a housing unit 20 that accommodates the stack member 18. The stack member 18 includes a cell stack 22 formed by stacking a plurality of power generation cells 21. The fuel cell stack 12 is arranged so that the stacking direction (arrow A direction) of the plurality of power generation cells 21 is horizontal. In the following description, the stacking direction of the plurality of power generation cells 21 is sometimes referred to as simply the "stacking direction".

[0026] exist Figure 1 In the embodiment, first wiring member 24a and first insulating plate 26a are sequentially arranged at one end (the end in the direction of arrow symbol A1) of the stacking direction of single cell stack 22 toward the outside (the direction of arrow symbol A1). Second wiring member 24b and second insulating plate 26b are sequentially arranged at the other end (the end in the direction of arrow symbol A2) of the stacking direction of single cell stack 22 toward the outside (the direction of arrow symbol A2). Stack member 18 includes single cell stack 22, first wiring member 24a, first insulating plate 26a, second wiring member 24b, and second insulating plate 26b.

[0027] First wiring member 24a and second wiring member 24b collect the electric power generated by each power generating cell 21. First wiring member 24a and second wiring member 24b are respectively formed in a plate shape (quadrilateral plate shape). First wiring member 24a and second wiring member 24b are respectively made of a conductive metal material such as pure copper, copper alloy, pure aluminum or aluminum alloy.

[0028] First wiring member 24a is disposed in first recess 28a formed on the inner surface (the surface in the direction of arrow symbol A2) of first insulating plate 26a. First wiring member 24a is in electrical contact with power generating cell 21 located at one end in the stacking direction (the end in the direction of arrow symbol A1). The thickness of first wiring member 24a along the stacking direction is greater than the thickness of power generating cell 21.

[0029] Second wiring member 24b is disposed in second recess 28b formed on the inner surface (the surface in the direction of arrow symbol A1) of second insulating plate 26b. Second wiring member 24b is in electrical contact with power generating cell 21 located at the other end in the stacking direction (the end in the direction of arrow symbol A2). The thickness of second wiring member 24b along the stacking direction is greater than the thickness of power generating cell 21. The shapes and sizes of first wiring member 24a and second wiring member 24b can be appropriately set.

[0030] The first insulating plate 26 a and the second insulating plate 26 b are each formed of a resin material having electrical insulation properties in a quadrilateral shape, for example.

[0031] like Figure 4 As shown, the power generation cell 21 has a horizontally long rectangular shape. The power generation cell 21 has an electrolyte membrane-electrode assembly with a resin frame (hereinafter referred to as "MEA 30 with a resin frame"), a first separator member 32, and a second separator member 34. The MEA 30 with a resin frame is disposed between the first separator member 32 and the second separator member 34.

[0032] The first partition member 32 and the second partition member 34 are respectively formed by stamping a thin metal plate into a corrugated cross section. The thin metal plate is, for example, a steel plate, a stainless steel plate, an aluminum plate, or a plated steel plate. The thin metal plate may also be a stainless steel plate with a surface treatment for corrosion prevention or an aluminum plate with a surface treatment for corrosion prevention. The first partition member 32 and the second partition member 34 are joined to each other by a plurality of joining lines not shown to form a joined partition 33.

[0033] The resin-framed MEA 30 includes an electrolyte membrane-electrode assembly (hereinafter referred to as “MEA 36 ”) and a resin frame member 38 (resin frame portion, resin film) that is bonded to the outer periphery of the MEA 36 and surrounds the outer periphery.

[0034] Figure 5In the embodiment, MEA 36 has: an electrolyte membrane 40; a cathode electrode 42, which is provided on one surface 40a of the electrolyte membrane 40; and an anode electrode 44, which is provided on the other surface 40b of the electrolyte membrane 40. The electrolyte membrane 40 is, for example, a solid polymer electrolyte membrane (cation exchange membrane). The solid polymer electrolyte membrane is, for example, a perfluorosulfonic acid film containing water. The electrolyte membrane 40 is sandwiched between the cathode electrode 42 and the anode electrode 44. The electrolyte membrane 40 may also be a fluorine-based electrolyte membrane or an HC (hydrocarbon)-based electrolyte membrane.

[0035] like Figure 4 As shown, an oxidant gas supply through hole 46a, a cooling medium supply through hole 48a, and a fuel gas discharge through hole 50b are provided at one end edge of the long side direction of each power generation unit cell 21. One end edge of the long side direction of the power generation unit cell 21 is the end edge of the arrow symbol B1 direction of the power generation unit cell 21. The oxidant gas supply through hole 46a, the cooling medium supply through hole 48a, and the fuel gas discharge through hole 50b are arranged along the short side direction of the power generation unit cell 21. The short side direction of the power generation unit cell 21 is the direction along the arrow symbol C direction.

[0036] The oxidant gas (e.g., oxygen-containing gas) as one of the reaction gases flows through the oxidant gas supply passage 46a in the direction of arrow A2. The cooling medium (e.g., pure water, ethylene glycol, oil, etc.) flows through the cooling medium supply passage 48a in the direction of arrow A2. The fuel gas (e.g., hydrogen-containing gas) as the other reaction gas flows through the fuel gas discharge passage 50b in the direction of arrow A1.

[0037] A fuel gas supply passage 50a, a cooling medium discharge passage 48b, and an oxidant gas discharge passage 46b are provided at the other end edge portion in the longitudinal direction of each power generation unit cell 21 (the end edge portion in the direction of arrow symbol B2). The fuel gas supply passage 50a, the cooling medium discharge passage 48b, and the oxidant gas discharge passage 46b are arranged in a row along the direction of arrow symbol C.

[0038] The fuel gas flows through the fuel gas supply passage 50a in the direction of arrow A2. The coolant flows through the coolant discharge passage 48b in the direction of arrow A1. The oxidant gas flows through the oxidant gas discharge passage 46b in the direction of arrow A1.

[0039] The arrangement, shape, and size of the above-mentioned communication holes (oxidant gas supply communication holes 46 a and the like) are not limited to the present embodiment, and may be appropriately set according to required specifications.

[0040] like Figure 2 and Figure 4As shown, the first separator member 32 includes a first separator body 52 in the form of a metal plate. An oxidant gas flow path 54 (reactant gas flow path) extending along the long side direction (arrow symbol B direction) of the power generation cell 21 is provided on the surface of the first separator body 52 facing the MEA 30 with a resin frame (hereinafter referred to as "surface 52a"). The oxidant gas flow path 54 is connected to the oxidant gas supply connecting hole 46a and the oxidant gas discharge connecting hole 46b so that a fluid can flow. The oxidant gas flow path 54 supplies the oxidant gas as a reactant gas to the cathode electrode 42.

[0041] A first sealing portion 56 for preventing leakage of a fluid serving as a reaction gas (oxidant gas or fuel gas) or a cooling medium is provided on a surface 52a of the first separator body 52. ​​The first sealing portion 56 is pressed against one surface 38a of the resin frame member 38 (see Figure 5 ). When viewed from the separator thickness direction (arrow A direction), the first sealing portion 56 extends in a straight line. However, when viewed from the separator thickness direction, the first sealing portion 56 may extend in a wave shape.

[0042] The first sealing portion 56 includes a plurality of first communication hole sealing portions 60 that surround a plurality of communication holes (such as the oxidizing gas supply communication hole 46 a ) individually, and a first flow path sealing portion 58 that is provided on the outer periphery of the first separator body 52 .

[0043] like Figure 5 As shown, the first sealing portion 56 includes: a first sealing protrusion 62, which protrudes toward the MEA 30 with a resin frame; and a first resin member 64, which is provided on the first sealing protrusion 62. The first sealing protrusion 62 is integrally formed with the first separator body 52 by stamping. The first sealing protrusion 62 is elastically deformed by the compressive load in the direction of the arrow symbol A.

[0044] like Figure 4 and Figure 6 As shown, the second separator member 34 includes a second separator body 66 in the form of a metal plate. A fuel gas flow path 68 (reactant gas flow path) extending along the long side direction (arrow symbol B direction) of the power generation cell 21 is provided on the surface of the second separator body 66 facing the MEA 30 with a resin frame (hereinafter referred to as "surface 66a"). The fuel gas flow path 68 is connected to the fuel gas supply connecting hole 50a and the fuel gas discharge connecting hole 50b so that fluid can flow. The fuel gas flow path 68 supplies the fuel gas as the reactant gas to the anode electrode 44.

[0045] A second sealing portion 70 is provided on the surface 66a of the second separator body 66 to prevent leakage of a fluid serving as a reaction gas (oxidant gas or fuel gas) or a cooling medium. The second sealing portion 70 is pressed against the other surface 38b of the resin frame member 38 (see Figure 5 ). When viewed from the separator thickness direction (arrow A direction), the second sealing portion 70 extends in a straight line. However, the second sealing portion 70 may extend in a wave shape when viewed from the separator thickness direction.

[0046] The second sealing portion 70 is arranged so as to overlap the first sealing portion 56 when viewed from the stacking direction (arrow A direction) of the plurality of power generation cells 21. The second sealing portion 70 includes a plurality of second communication hole sealing portions 74 that surround a plurality of communication holes (such as the oxidant gas supply communication hole 46a) individually, and a second flow path sealing portion 72 that is provided on the outer periphery of the second separator body 66.

[0047] like Figure 5 As shown, the second sealing portion 70 includes: a second sealing protrusion 76 protruding toward the MEA 30 with a resin frame; and a second resin member 78 provided on the second sealing protrusion 76. The second sealing protrusion 76 is integrally formed with the second separator body 66 by stamping. The second sealing protrusion 76 is elastically deformed by the compressive load in the direction of the arrow symbol A.

[0048] exist Figure 4 In the embodiment, a cooling medium flow path 80 is formed between the back surface 52b of the first separator body 52 and the back surface 66b of the second separator body 66, and the cooling medium flow path 80 is connected to the cooling medium supply connecting hole 48a and the cooling medium discharge connecting hole 48b so that fluid can flow. The cooling medium flow path 80 is formed by overlapping the back surface shape of the first separator body 52 and the back surface shape of the second separator body 66.

[0049] like Figures 2 to 4 and Figure 6 As shown, four load bearing parts 82 (first load bearing part 82a, second load bearing part 82b, third load bearing part 82c and fourth load bearing part 82d) are provided in each power generation cell 21. When an external load in the direction of arrow symbol B acts on the fuel cell stack 12, the four load bearing parts 82 bear the external load.

[0050] Each load receiving portion 82 is joined to the outer edge of the power generation cell 21 in a manner protruding outward from the power generation cell 21. A positioning hole 88 is formed in each load receiving portion 82. A rod (not shown) is inserted through the positioning hole 88, and the rod is used to position the power generation cell 21 in the surface direction when manufacturing the fuel cell stack 12 (when stacking the power generation cells 21).

[0051] exist Figure 2 and Figure 4 In the embodiment, the first load receiving portion 82a is provided on the first baffle body 52 so as to protrude downward (in the direction of arrow symbol C1) from the lower end portion of the first baffle body 52. ​​The first load receiving portion 82a is located at a position offset in the direction of arrow symbol B2 relative to the center of the long side direction (width direction, direction of arrow symbol B) of the first baffle body 52.

[0052] The second load receiving portion 82b is provided on the first separator body 52 so as to protrude upward (in the direction of arrow C2) from the upper end of the first separator body 52. ​​The second load receiving portion 82b is located at a position offset from the center of the first separator body 52 in the longitudinal direction in the direction of arrow B1.

[0053] exist Figure 4 and Figure 6 In the embodiment, the third load receiving portion 82c is provided on the second baffle body 66 so as to protrude downward from the lower end portion of the second baffle body 66. The third load receiving portion 82c is located at a position offset in the direction of the arrow symbol B2 relative to the center in the long side direction (width direction, arrow symbol B direction) of the second baffle body 66. The third load receiving portion 82c faces the first load receiving portion 82a.

[0054] The fourth load receiving portion 82d is provided on the second baffle body 66 so as to protrude upward from the upper end portion of the second baffle body 66. The fourth load receiving portion 82d is located at a position offset in the direction of arrow B1 relative to the longitudinal center of the second baffle body 66. The fourth load receiving portion 82d faces the second load receiving portion 82b.

[0055] like Figure 1 As shown, when viewed from a direction orthogonal to the direction of arrow symbol A, the housing unit 20 is rectangular in shape, and the long side of the housing unit 20 extends in the direction of arrow symbol A. The housing unit 20 includes: a stack housing 90, which forms a stack storage space S1 for storing the stack member 18; and an auxiliary equipment housing 92, which forms an auxiliary equipment storage space S2 for storing the auxiliary equipment 14 for the fuel cell. The stack housing 90 and the auxiliary equipment housing 92 are adjacent to each other in the direction of arrow symbol A. In other words, the auxiliary equipment housing 92 is located in the direction of arrow symbol A1 of the stack housing 90.

[0056] The stack housing 90 includes: a square cylindrical peripheral wall housing 94 that covers the outer peripheral surface of the stack member 18; a first end panel portion 96 that is disposed at one end (the end in the direction of arrow symbol A1) of the peripheral wall housing 94; and a second end panel portion 98 that is disposed at the other end (the end in the direction of arrow symbol A2) of the peripheral wall housing 94. That is, the stack storage space S1 is formed by the peripheral wall housing 94, the first end panel portion 96, and the second end panel portion 98.

[0057] exist Figures 1 to 3 In the embodiment, the peripheral wall housing 94 has: a lower wall portion 94a; a pair of side wall portions 94b and 94c, which protrude upward from the lower wall portion 94a; and an upper wall portion 94d, which connects the protruding ends of the pair of side wall portions 94b and 94c to each other. Figure 2 In the embodiment, a first support portion 100 protruding upward is provided on the inner surface of the lower wall portion 94a. The first support portion 100 extends along the direction of arrow A over the entire length of the peripheral wall housing 94. A first groove portion 102 for accommodating the first load receiving portion 82a and the third load receiving portion 82c is formed at the protruding end of the first support portion 100. The first groove portion 102 extends along the direction of arrow A.

[0058] Two first support surfaces 104 are provided on the first support portion 100. The two first support surfaces 104 are located so as to sandwich the first load receiving portion 82a and the third load receiving portion 82c from the direction of arrow symbol B. When an external load in the direction of arrow symbol B acts on the fuel cell stack 12, the first load receiving portion 82a and the third load receiving portion 82c come into contact with any one of the two first support surfaces 104, thereby suppressing positional deviation of the plurality of power generation cells 21 in the direction of arrow symbol B.

[0059] like Figure 2 As shown, the upper wall portion 94d includes a first portion 106, a second portion 108, and a connecting portion 110. The first portion 106 covers the second load receiving portion 82b and the fourth load receiving portion 82d from above. The second portion 108 is located below (in the direction of arrow symbol C1) the outer surface (upper surface) of the first portion 106. The connecting portion 110 connects the first portion 106 and the second portion 108 to each other.

[0060] The second portion 108 is located in the direction of arrow symbol B2 relative to the first portion 106. The first portion 106, the second portion 108 and the connecting portion 110 extend over the entire length of the peripheral wall portion 154 in the direction of arrow symbol A (see Figure 7). The connecting portion 110 extends in a manner inclined downward from the first portion 106 toward the second portion 108. The connecting portion 110 is located above the center of the power generation cell 21 in the direction of the arrow symbol B. The interval L1 between the inner surface of the first portion 106 and the outer surface of the cell stack 22 (the upper end of the bonding separator 33) is larger than the interval L2 between the inner surface of the second portion 108 and the outer surface of the cell stack 22 (the upper end of the bonding separator 33).

[0061] exist Figure 2 and Figure 3 In the embodiment, a second support portion 112 protruding downward is provided on the inner surface of the first portion 106. The second support portion 112 extends along the direction of arrow A over the entire length of the peripheral wall housing 94. A second groove portion 114 for accommodating the second load receiving portion 82b and the fourth load receiving portion 82d is formed at the protruding end of the second support portion 112. The second groove portion 114 extends along the direction of arrow A.

[0062] Two second support surfaces 116 are provided on the second support portion 112. The two second support surfaces 116 are located so as to sandwich the second load receiving portion 82b and the fourth load receiving portion 82d from the direction of arrow symbol B. When an external load in the direction of arrow symbol B acts on the fuel cell stack 12, the second load receiving portion 82b and the fourth load receiving portion 82d come into contact with any of the two second support surfaces 116, thereby suppressing positional deviation of the plurality of power generation cells 21 in the direction of arrow symbol B.

[0063] like Figure 1 and Figure 7 As shown, first through hole 118 and second through hole 120 are formed in first portion 106. Upper wall portion 94d includes: a first end, which is located at one end (arrow A1 direction) of the stacking direction of multiple power generation cells 21; and a second end, which is located at the other end (arrow A2 direction) of the stacking direction of multiple power generation cells 21. First through hole 118 is located between the center of the stacking direction of multiple power generation cells 21 in upper wall portion 94d and the first end. In other words, first through hole 118 is located at a position closer to the first wiring member 24a side (auxiliary device case 92 side, arrow A1 direction) than the center of the length direction of stack member 18 (arrow A direction). Second through hole 120 is located between the center of the stacking direction of multiple power generation cells 21 in upper wall portion 94d and the second end. In other words, second through hole 120 is located at a position closer to the second wiring member 24b side (arrow A2 direction) than the center of the length direction of stack member 18. That is, second through hole 120 is located closer to second wiring member 24b than first through hole 118 is.

[0064] exist Figure 7In the figure, the first through hole 118 and the second through hole 120 are located at a position offset in the direction of the arrow symbol B1 relative to the center of the power generation cell 21 in the direction of the arrow symbol B. The first through hole 118 is formed in a perfect circular shape. The second through hole 120 is a long hole extending along the stacking direction (the direction of the arrow symbol A). Specifically, the second through hole 120 includes: a central hole portion 122 in a rectangular shape, which extends along the stacking direction; and two end hole portions 124, which are connected to both ends of the central hole portion 122 in the direction of the arrow symbol A. Each end hole portion 124 is formed in a semicircular shape. That is, the two ends of the second through hole 120 in the stacking direction (the direction of the arrow symbol A) are curved in an arc shape.

[0065] The length L3 of the second through hole 120 along the stacking direction is greater than the length L4 of the first through hole 118 along the stacking direction (the diameter of the first through hole 118). The length L5 of the second through hole 120 (central hole portion 122) along the direction of arrow symbol B is the same as the length L6 of the first through hole 118 along the direction of arrow symbol B (the diameter of the first through hole 118). The center P1 of the first through hole 118 and the center P2 of the second through hole 120 are located on a straight line La extending along the direction of arrow symbol A.

[0066] The shapes of the first through hole 118 and the second through hole 120 can be appropriately set. The first through hole 118 is not limited to a perfect circular shape, but may be a long hole extending in the direction of arrow symbol A (the same shape as the second through hole 120). Even in this case, the length L3 of the second through hole 120 along the stacking direction is greater than the length L4 of the first through hole 118 along the stacking direction. The first through hole 118 and the second through hole 120 may each be an elliptical shape extending in the stacking direction. The length L6 of the first through hole 118 along the direction of arrow symbol B and the length L5 of the second through hole 120 along the direction of arrow symbol B may also be different from each other. The center P1 of the first through hole 118 and the center P2 of the second through hole 120 may not be located on a straight line La extending in the direction of arrow symbol A.

[0067] like Figure 1 As shown, the first end panel portion 96 is joined to the peripheral wall housing 94 by bolts (not shown) in such a manner as to seal a first opening portion 130 formed at one end of the peripheral wall housing 94. An annular sealing member 132 formed of an elastic material is installed between the first end panel portion 96 and the peripheral wall housing 94 along the outer periphery of the first opening portion 130.

[0068] Second end panel portion 98 is joined to peripheral wall case 94 by bolts 136 so as to close second opening portion 134 formed at the other end of peripheral wall case 94. An annular sealing member 138 formed of an elastic material is installed between second end panel portion 98 and peripheral wall case 94 along the outer periphery of second opening portion 134. Second end panel portion 98 is fastened to peripheral wall case 94 by bolts 136, so that a compressive load is applied to single cell stack 22. Plate-shaped backing plate 139 is provided between second end panel portion 98 and second insulating plate 26b. The compressive load is adjusted by the thickness (number of sheets) of backing plate 139, and the position of second wiring member 24b in the stacking direction is changed.

[0069] The auxiliary equipment housing 92 is a protective housing for protecting the auxiliary equipment 14 for fuel cells accommodated in the auxiliary equipment storage space S2. As the auxiliary equipment 14 for fuel cells, for example, a gas-liquid separator, an ejector, an ejector, a fuel gas pump, a valve, etc., which are not shown in the figure, can be listed. The auxiliary equipment housing 92 is formed by mutually joining a box-like first housing member 140 and a box-like second housing member 142 by bolt members 143. The first housing member 140 opens in the direction of arrow symbol A1. The second housing member 142 opens in the direction of arrow symbol A2.

[0070] The first end surface plate portion 96 serves as both a wall portion of the stack case 90 and a wall portion of the auxiliary equipment case 92. In other words, the first end surface plate portion 96 is a partition wall between the stack storage space S1 and the auxiliary equipment storage space S2.

[0071] exist Figure 1 and Figure 2 In the embodiment, the electric device unit 16 is arranged on the outer surface of the upper wall portion 94d of the stack housing 90. The electric device unit 16 has: an electric device unit body 144; and an electric device housing 146, which accommodates the electric device unit body 144. The electric device unit body 144 includes a contactor (switching device) and a control unit, etc. The control unit controls the voltage of the electric power generated by the fuel cell stack 12. In addition, the electric device unit body 144 includes: a first terminal portion 145a, which is formed with a first hole 143a; and a second terminal portion 145b, which is formed with a second hole 143b (refer to Figure 8 ).

[0072] The electric device case 146 includes: a case body 148, which is open at the top; and a cover 150, which closes the upper opening of the case body 148. The case body 148 includes: a bottom wall 152; and a peripheral wall 154, which extends upward from the outer periphery of the bottom wall 152. The bottom wall 152 includes: a first bottom wall 156, which is provided on the outer surface (upper surface) of the first portion 106 of the stack case 90; a second bottom wall 158, which is provided on the outer surface (upper surface) of the second portion 108 of the stack case 90; and a wall 160, which connects the first bottom wall 156 and the second bottom wall 158 to each other.

[0073] like Figure 1 and Figure 8 As shown, a first communicating hole 162 communicating with the first through hole 118 and a second communicating hole 164 communicating with the second through hole 120 are formed through the first bottom wall portion 156. The first communicating hole 162 is formed to have the same size and shape as the first through hole 118. The center of the first communicating hole 162 is located at a position overlapping with the center P1 of the first through hole 118 or at a position close to the center P1 when viewed from above. The second communicating hole 164 is formed to have the same size and shape as the second through hole 120. The center of the second communicating hole 164 is located at a position overlapping with the center P2 of the second through hole 120 or at a position close to the center P2 when viewed from above.

[0074] The first communication hole 162 may be formed larger than the first through hole 118. In addition, the second communication hole 164 may be formed larger than the second through hole 120.

[0075] like Figure 8 As shown, the fuel cell stack 12 includes a first power extraction member 170 a and a second power extraction member 170 b for transmitting the power generated by each power generating cell 21 to the electrical device unit 16 .

[0076] First power lead-out member 170a electrically connects first wiring member 24a and first terminal portion 145a of electric device unit main body 144. First power lead-out member 170a has a first conductor portion 172a and a first connecting portion 174a.

[0077] The first conductor part 172a is a busbar formed in a strip shape. The first conductor part 172a is made of, for example, copper, aluminum, stainless steel, titanium or a metal having the above substances as a main component. The first conductor part 172a is an integrally formed part in the shape of the letter L. The first conductor part 172a has: a first fixed part 176a extending in the up-down direction (the direction of the arrow symbol C); and a first extension part 178a extending in the stacking direction (the direction of the arrow symbol A).

[0078] One end (lower end) of first fixing portion 176a is electrically connected to first wiring member 24a by soldering, caulking, welding, screwing, etc. The other end (upper end) of first fixing portion 176a is located above first insulating plate 26a (single cell stack 22).

[0079] The first extension portion 178a extends from the other end of the first fixing portion 176a in the direction of arrow A2. The first extension portion 178a is located in the space S3 between the first portion 106 of the upper wall portion 94d and the cell stack 22. In other words, the first extension portion 178a is separated from both the cell stack 22 and the first portion 106.

[0080] exist Figure 2 and Figure 3 In the figure, the first extension portion 178a is adjacent to the second support portion 112 in the direction of arrow symbol B2. The first extension portion 178a is separated from the second support portion 112.

[0081] exist Figure 8 In the embodiment, only one first mounting hole 180a is formed through the first extension portion 178a for mounting the first connection portion 174a. The first connection portion 174a is fixed to the first mounting hole 180a of the first conductor portion 172a in an immovable state. The first connection portion 174a includes a first connection portion body 182a and a first fastening member 184a.

[0082] The first connection part body 182a is made of, for example, copper, aluminum, stainless steel, titanium or a metal having the above substances as a main component. The first connection part body 182a is formed into a cylindrical shape. The first connection part body 182a has an outer peripheral surface with a circular cross-section. The first connection part body 182a extends in the up-down direction in a manner of inserting the first through hole 118 and the first connecting hole 162. One end surface of the first connection part body 182a contacts the upper surface of the first extension part 178a. The other end surface of the first connection part body 182a contacts the lower surface of the first terminal part 145a.

[0083] exist Figure 7 In the embodiment, the outer diameter D1 of the first connection part body 182a is smaller than the lengths L4 and L6 of the first through hole 118. That is, a gap is formed between the first connection part body 182a and the inner surface forming the first through hole 118 so as to ensure electrical insulation.

[0084] like Figure 8As shown, the first fastening member 184a screws the first conductor portion 172a and the first terminal portion 145a together by threads. Specifically, the first fastening member 184a has a first fixing nut 186a and a first bolt portion 188a. The first fixing nut 186a is fixed to the first extension portion 178a. The first bolt portion 188a screws the first terminal portion 145a to the bottom by screwing with the first fixing nut 186a.

[0085] The first fixing nut 186a is fixed to the lower surface of the first extension portion 178a by welding, for example. The first bolt portion 188a includes: a first bolt body 190a; and a first pressing portion 192a, which is provided on the first bolt body 190a. The first bolt body 190a extends in the up-down direction in a manner of being inserted through the first mounting hole 180a of the first extension portion 178a, the inner hole of the first connection portion body 182a, and the first hole 143a of the first terminal portion 145a.

[0086] An external threaded portion 196a is formed at one end of the first bolt body 190a and is threadedly engaged with the internal threaded portion 194a of the first fixing nut 186a. An external threaded portion 200a is formed at the other end of the first bolt body 190a and is threadedly engaged with the internal threaded portion 198a formed on the first pressing portion 192a. The outer diameter of the first pressing portion 192a is larger than the diameter (aperture) of the first hole 143a of the first terminal portion 145a. In other words, the first pressing portion 192a abuts against the upper surface of the first terminal portion 145a.

[0087] Second power lead-out member 170b electrically connects second wiring member 24b and second terminal portion 145b of electric device unit main body 144. Second power lead-out member 170b has second conductor portion 172b and second connection portion 174b.

[0088] The second conductor portion 172b is a busbar formed in a strip shape. The second conductor portion 172b is made of the same material as the first conductor portion 172a described above. The second conductor portion 172b is an integrally formed part in the shape of the letter L. The second conductor portion 172b has: a second fixed portion 176b extending in the up-down direction (the direction of the arrow symbol C); and a second extension portion 178b extending in the stacking direction (the direction of the arrow symbol A).

[0089] One end (lower end) of second fixing portion 176b is electrically connected to second wiring member 24b by soldering, caulking, welding, screwing, etc. The other end (upper end) of second fixing portion 176b is located above second insulating plate 26b (single cell stack 22).

[0090] The second extension portion 178b extends from the other end of the second fixing portion 176b in the direction of arrow A1. The second extension portion 178b is located in the space S3 between the first portion 106 of the upper wall portion 94d and the cell stack 22. In other words, the second extension portion 178b is separated from both the cell stack 22 and the first portion 106.

[0091] exist Figure 2 and Figure 3 In the figure, the second extension portion 178b is adjacent to the second support portion 112 in the direction of arrow symbol B2. The second extension portion 178b is separated from the second support portion 112.

[0092] exist Figure 8 In the embodiment, only one second mounting hole 180b is formed through the second extension portion 178b for mounting the second connection portion 174b. The second connection portion 174b is fixed to the second mounting hole 180b (mounting portion) of the second conductor portion 172b in an immovable state. The second connection portion 174b includes a second connection portion body 182b and a second fastening member 184b.

[0093] The second connection part body 182b is made of the same material as the first connection part body 182a described above. The second connection part body 182b is formed into a cylindrical shape. The second connection part body 182b has an outer peripheral surface with a circular cross-section. The second connection part body 182b extends in the up-down direction in a manner of inserting the second through hole 120 and the second connecting hole 164. One end surface of the second connection part body 182b contacts the upper surface of the second extension part 178b. The other end surface of the second connection part body 182b contacts the lower surface of the second terminal part 145b.

[0094] exist Figure 7 In the embodiment, the outer diameter D2 of the second connection part body 182b is the same as the outer diameter D1 of the first connection part body 182a, and the outer diameter D2 of the second connection part body 182b is smaller than the lengths L3 and L5 of the second through hole 120. That is, a gap is formed between the second connection part body 182b and the inner surface forming the second through hole 120 so as to ensure electrical insulation.

[0095] like Figure 8 As shown, the second fastening member 184b tightens the second conductor portion 172b and the second terminal portion 145b to each other by threading. Specifically, the second fastening member 184b has a second fixing nut 186b and a second bolt portion 188b. The second fixing nut 186b is fixed to the second extension portion 178b. The second bolt portion 188b fastens the second terminal portion 145b below by threading with the second fixing nut 186b.

[0096] The second fixing nut 186b is fixed to the lower surface of the second extension portion 178b by welding, for example. The second bolt portion 188b includes: a second bolt body 190b; and a second pressing portion 192b, which is provided on the second bolt body 190b. The second bolt body 190b extends in the up-down direction in a manner of being inserted through the second mounting hole 180b of the second extension portion 178b, the inner hole of the second connection portion body 182b, and the second hole 143b of the second terminal portion 145b.

[0097] An external threaded portion 196b is formed at one end of the second bolt body 190b and is threadedly engaged with the internal threaded portion 194b of the second fixing nut 186b. An external threaded portion 200b is formed at the other end of the second bolt body 190b and is threadedly engaged with the internal threaded portion 198b formed on the second pressing portion 192b. The outer diameter of the second pressing portion 192b is greater than the diameter (aperture) of the second hole 143b of the second terminal portion 145b. In other words, the second pressing portion 192b abuts against the upper surface of the second terminal portion 145b.

[0098] The operation of the fuel cell stack 12 configured in this manner will be described below.

[0099] First, if Figure 4 As shown, the oxidant gas is introduced from the oxidant gas supply passage 46a to the oxidant gas flow path 54 of the first separator member 32. The oxidant gas moves along the oxidant gas flow path 54 in the direction of arrow B and is supplied to the cathode electrode 42 of the MEA 36.

[0100] On the other hand, Figure 4 and Figure 6 As shown, the fuel gas is introduced from the fuel gas supply passage 50a to the fuel gas flow path 68 of the second separator member 34. The fuel gas moves in the direction of arrow B along the fuel gas flow path 68 and is supplied to the anode electrode 44 of the MEA 36.

[0101] Therefore, in each MEA 36 , the oxidant gas supplied to the cathode electrode 42 and the fuel gas supplied to the anode electrode 44 are consumed by electrochemical reactions in the first electrode catalyst layer and the second electrode catalyst layer. As a result, power generation is performed.

[0102] Then, if Figure 4 As shown, the oxidant gas supplied to the cathode electrode 42 and consumed is discharged along the oxidant gas discharge passage 46b in the direction of arrow A. Similarly, the fuel gas supplied to the anode electrode 44 and consumed is discharged along the fuel gas discharge passage 50b in the direction of arrow A.

[0103] The cooling medium supplied to the cooling medium supply passage 48a is introduced into the cooling medium flow path 80 formed between the first separator member 32 and the second separator member 34. After being introduced into the cooling medium flow path 80, the cooling medium flows in the direction of arrow B. After cooling the MEA 36, the cooling medium is discharged from the cooling medium discharge passage 48b.

[0104] Next, a method for manufacturing the fuel cell system 10 according to the present embodiment will be described.

[0105] like Fig. 9 As shown, in the manufacturing method of the fuel cell stack 12, the first end panel portion 96 (only the first shell member 140) is fixed to one end of the peripheral wall shell 94. Then, the first shell member 140 is mounted on the support stand 300 in a state where the surface 97 of the first end panel portion 96 on the side opposite to the peripheral wall shell 94 is directed downward in the vertical direction.

[0106] Thereafter, first insulating plate 26a, first wiring member 24a, a plurality of power generation cells 21 (cell stack 22), second wiring member 24b, second insulating plate 26b, and spacer 139 are sequentially stacked in peripheral wall case 94 to form stack member 18. Then, second end panel portion 98 is fastened to the other end of peripheral wall case 94 by bolts 136. At this time, second end panel portion 98 presses second insulating plate 26b toward cell stack 22. Thus, a compressive load is applied to cell stack 22.

[0107] Then, the fuel cell auxiliary device 14 is fixed to the first housing member 140, and the second housing member 142 is mounted to the first housing member 140 in a manner covering the fuel cell auxiliary device 14. Thus, the manufacture of the fuel cell stack 12 is completed. Then, the electric device unit 16 is mounted on the upper wall portion 94d of the stack housing 90 of the fuel cell stack 12.

[0108] Specifically, the shell body 148 of the electrical device shell 146 is fixed to the upper wall portion 94d of the stack shell 90. At this time, the first connecting hole 162 is located on the first through hole 118. In addition, the second connecting hole 164 is located on the second through hole 120. Then, the first conductor portion 172a and the first terminal portion 145a are connected to each other using the first connecting portion 174a. The second conductor portion 172b and the second terminal portion 145b are connected to each other using the second connecting portion 174b. Thereafter, the cover portion 150 is mounted on the shell body 148, thereby completing the manufacture of the fuel cell system 10 of this embodiment.

[0109] In this case, the fuel cell stack 12 according to the present embodiment can achieve the following effects.

[0110] Fuel cell stack 12 manufactured as described above causes a deviation in the position of second wiring member 24b in the stacking direction relative to first wiring member 24a due to the assembly tolerance of a plurality of power generating cells 21 and the dimensional tolerance of each power generating cell 21. The assembly tolerance of a plurality of power generating cells 21 includes the difference in the elastic deformation amount of each power generating cell 21 in the stacking direction (the elastic deformation amount of first sealing portion 56 and second sealing portion 70).

[0111] Therefore, if Figure 8 and Fig.10 As shown, the second mounting hole 180b of the second conductor portion 172b and the second through hole 120 are easily offset in the stacking direction. In other words, the second connection portion body 182b (second power extraction member 170b) and the second through hole 120 are easily offset in the stacking direction. In other words, the second connection portion body 182b is easily offset in the direction of arrow symbol A1 or arrow symbol A2 relative to the center P2 of the second through hole 120.

[0112] However, in the present embodiment, length L3 of second through hole 120 along the stacking direction is greater than length L4 of first through hole 118 along the stacking direction. Therefore, positional deviation in the stacking direction between second power lead-out member 170b (second connecting portion 174b) and second through hole 120 can be absorbed by second through hole 120. Thus, even when second wiring member 24b is positionally displaced relative to first wiring member 24a in the stacking direction, second power lead-out member 170b (second connecting portion 174b) can be reliably inserted into second through hole 120. In addition, since length L4 of first through hole 118 along the stacking direction does not exceed the required length, reduction in rigidity of stack case 90 can be suppressed.

[0113] Stack case 90 includes a first end portion that accommodates first wiring member 24a and a second end portion that accommodates second wiring member 24b. An auxiliary equipment case 92 for protecting auxiliary equipment 14 for the fuel cell is provided at the first end portion of stack case 90.

[0114] With such a structure, the power generating cells 21 can be stacked with the auxiliary equipment case 92 side as a reference.

[0115] Second power extraction member 170b includes: a second conductor portion 172b which is located in stack case 90 and electrically connected to second wiring member 24b; and a second connecting portion 174b which is electrically connected to second conductor portion 172b and extends in the up-down direction so as to be inserted into second through hole 120.

[0116] According to such a configuration, after the stack member 18 is disposed in the stack case 90 , the second connection portion 174 b can be connected to the second conductor portion 172 b from the outside of the stack case 90 .

[0117] The second connection portion 174 b has an outer peripheral surface with a circular cross-section, and both ends of the second through hole 120 in the stacking direction are curved in an arc shape when viewed from above.

[0118] According to such a structure, it is possible to effectively suppress the second connection portion 174 b from coming into contact with the inner surface forming the second through hole 120 (ground fault).

[0119] The second through hole 120 includes a rectangular central hole portion 122 extending in the stacking direction and semicircular end hole portions 124 communicating with both ends of the central hole.

[0120] According to such a structure, the second through hole 120 can be formed longer in the stacking direction without extending the second through hole 120 in the direction of arrow B orthogonal to the stacking direction to a length exceeding a necessary length.

[0121] Each of the plurality of power generating cells 21 is provided with a load receiving portion 82 protruding upward. The upper wall portion 94d includes a first portion 106 located above the load receiving portion 82, a second portion 108 located below the outer surface of the first portion 106, and a connecting portion 110 connecting the first portion 106 and the second portion 108. The first portion 106 is provided with a first through hole 118 and a second through hole 120, and a first power extraction member 170a (first conductor portion 172a) and a second power extraction member 170b (second conductor portion 172b) are arranged in a space between the first portion 106 and the cell stack 22.

[0122] According to such a configuration, the space above the second portion 108 can be effectively utilized.

[0123] An electric device unit 16 electrically connected to the first power extraction member 170 a and the second power extraction member 170 b is arranged on the outer surface of the second portion 108 .

[0124] According to such a structure, the height dimension of the stack case 90 and the electric device unit 16 can be suppressed to be relatively small. Thus, the fuel cell system 10 can be miniaturized.

[0125] The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

[0126] The above-described embodiments are summarized as follows.

[0127] The above embodiment discloses a fuel cell system, which fuel cell system 10 comprises: a stack component 18, which has a single cell stack 22 formed by stacking a plurality of power generation cells 21 on each other, and a first wiring component 24a and a second wiring component 24b arranged at both ends of the single cell stack; and a stack shell 90, which accommodates the stack component. In the fuel cell system 10, there are: a first power extraction component 170a, which is electrically connected to the first wiring component; and a second power extraction component 170b, which is electrically connected to the second wiring component. The upper wall portion 94d of the stack shell is formed with: a first through hole 118 for inserting the first power extraction component; and a second through hole 120 for inserting the second power extraction component, and the length L3 of the second through hole along the stacking direction of the plurality of power generation cells is greater than the length L4 of the first through hole along the stacking direction.

[0128] Based on the above-mentioned fuel cell system, the stack shell may also include: a first end portion, which accommodates the first wiring component; and a second end portion, which accommodates the second wiring component, and an auxiliary equipment shell 92 for protecting the auxiliary equipment 14 for the fuel cell is provided at the first end portion of the stack shell.

[0129] Based on the above-mentioned fuel cell system, it may also be that the second power extraction component includes: a conductor portion 172b, which is located in the stack shell and is electrically connected to the second wiring member; and a connecting portion 174b, which is electrically connected to the conductor portion and extends in the up-down direction in a manner of being inserted into the second through hole.

[0130] Based on the above fuel cell system, the connection portion may have an outer peripheral surface having a circular cross-section, and both ends of the second through hole in the stacking direction may be curved in an arc shape when viewed from above.

[0131] Based on the above fuel cell system, the second through hole may include: a rectangular central hole portion 122 extending along the stacking direction; and semicircular end hole portions 124 communicating with both ends of the central hole portion.

[0132] Based on the above fuel cell system, the center P1 of the first through hole and the center P2 of the second through hole may be located on a straight line La extending along the stacking direction.

[0133] Based on the above fuel cell system, a length L6 of the first through hole in a direction perpendicular to the stacking direction may be the same as a length L5 of the second through hole in a direction perpendicular to the stacking direction.

[0134] Based on the above-mentioned fuel cell system, each of the plurality of power generation cells may be provided with a load-bearing portion 82 protruding upward, and the upper wall portion may include: a first portion 106, which is located above the load-bearing portion; a second portion 108, which is located below the outer surface of the first portion; and a connecting portion 110, which connects the first portion and the second portion to each other, and the first through hole and the second through hole are formed in the first portion, and the first power extraction component and the second power extraction component are arranged in the space S3 between the first portion and the cell stack.

[0135] Based on the above fuel cell system, an electric device unit 16 electrically connected to the first power extracting member and the second power extracting member may be arranged on the outer surface of the second portion.

[0136] Based on the above fuel cell system, the first through hole may be formed in a perfect circular shape.

Claims

1. A fuel cell system, the fuel cell system (10) comprising: a stack member (18) having a cell stack (22) formed by stacking a plurality of power generation cells (21) on each other, and a first wiring member (24a) and a second wiring member (24b) provided at both ends of the cell stack; and a stack case (90) for accommodating the stack member, wherein in the fuel cell system (10), have: a first power extracting member (170a) electrically connected to the first wiring member; and a second power extracting member (170b) electrically connected to the second wiring member, The upper wall portion (94d) of the stack housing is formed with: a first through hole (118) through which the first power extraction member is inserted; and a second through hole (120) through which the second power extraction member is inserted, The length (L3) of the second through hole along the stacking direction of the plurality of power generating cells is greater than the length of the first through hole along the stacking direction. A compressive load is applied to the pile member from the second wiring member toward the first wiring member.

2. The fuel cell system according to claim 1, characterized in that: The stack housing comprises: a first end portion receiving the first wiring member; and a second end portion receiving the second wiring member, An auxiliary equipment housing (92) for protecting auxiliary equipment (14) for a fuel cell is provided at the first end portion of the stack housing.

3. The fuel cell system according to claim 1, characterized in that: The second power extraction component comprises: a conductor portion (172b) located in the stack case and electrically connected to the second wiring member; and A connecting portion (174b) is electrically connected to the conductor portion and extends in the up-down direction in a manner inserted into the second through hole.

4. The fuel cell system according to claim 3, characterized in that: The connecting portion has an outer peripheral surface with a circular cross section, When viewed from above, both ends of the second through hole in the stacking direction are curved in an arc shape.

5. The fuel cell system according to claim 4, characterized in that: The second through hole comprises: a central hole portion (122) of rectangular shape extending along the stacking direction; and A semicircular end hole portion (124) is connected to both ends of the central hole portion.

6. The fuel cell system according to claim 1, characterized in that: The center (P1) of the first through hole and the center (P2) of the second through hole are located on a straight line (La) extending along the stacking direction.

7. The fuel cell system according to claim 1, characterized in that: A length (L6) of the first through hole in a direction perpendicular to the stacking direction is the same as a length (L5) of the second through hole in a direction perpendicular to the stacking direction.

8. The fuel cell system according to claim 1, characterized in that: Each of the plurality of power generating cells is provided with a load receiving portion (82) protruding upward. The upper wall portion has: a first portion (106) located above the load bearing portion; a second portion (108) located below an outer surface of the first portion; and a connecting portion (110) connecting the first portion and the second portion to each other, The first through hole and the second through hole are formed in the first portion, The first power extraction member and the second power extraction member are arranged in a space between the first portion and the cell stack (S3).

9. The fuel cell system according to claim 8, characterized in that: An electric device unit (16) electrically connected to the first power extraction member and the second power extraction member is arranged on the outer surface of the second portion.

10. The fuel cell system according to any one of claims 1 to 9, characterized in that: The first through hole is formed in a perfect circular shape.

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