Fuel battery stack case

Abstract

To provide a fuel battery stack case capable of generating power even in the case where a defective cell is detached while easily exchanging a fuel battery cell in a short time.SOLUTION: A fuel battery stack case 1 comprises: a case main body 11; a plurality of fixed metal plates 12 fixed in the case main body 11 with an interval in a lamination direction D1 of a fuel battery cell 3; a plurality of elastic bodies 13 having elastic property and conductivity in the lamination direction D1, and installed at the fixed metal plate 12; and a plurality of movable metal plates 14 supported by the fixed metal plate 12 via the elastic body 13, and movable in the lamination direction D1. The fuel battery cell 3 can be attached between the pair of movable metal plates 14 adjacently arranged in the lamination direction D1.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a fuel cell stack case.

Background Art

[0002] As a conventional fuel cell stack case for stacking and housing a plurality of fuel cell cells, for example, Patent Document 1 discloses a fuel cell stack in which an intermediate clamping plate through which stud bolts are passed is stacked in a cell stack to divide the cell stack into a plurality of cell blocks, and intermediate nuts are provided on both sides of the intermediate clamping plate in the stud bolts. In this fuel cell stack, when replacing a single cell in which a defect has occurred, the intermediate clamping plate and the intermediate nut adjacent to the replacement cell block including the defective cell are used to apply pressure to cell blocks other than the replacement cell block and release the pressure applied to the replacement cell block, and the replacement cell block is removed from the cell stack.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the replacement of a defective cell in the fuel cell stack of Patent Document 1, the following steps occur: the intermediate clamping plate is moved by tightening the intermediate nut to remove the replacement cell block from the cell stack, the replacement cell block is further disassembled to remove the defective cell, and then reassembled. The operation of replacing a defective cell including such steps is complicated and time-consuming. In addition, a gap is generated in the cell stack by removing the replacement cell block, and there is a problem that the fuel cell cannot be operated (generate electricity) until a new cell block is attached to the cell stack.

[0005] The present invention has been made paying attention to the above points, and an object thereof is to provide a fuel cell stack case that can exchange fuel cells easily and in a short time and can generate power even when a defective cell is removed.

Means for Solving the Problems

[0006] To achieve the above object, an aspect of the present invention provides a fuel cell stack case for stackably accommodating a plurality of fuel cells in an exchangeable manner. This fuel cell stack case has an opening that opens in a direction intersecting the stacking direction of the fuel cells, and a case body into which each of the fuel cells is inserted and removed through the opening, a plurality of fixed metal plates having a plate shape extending in the intersecting direction and fixed inside the case body at intervals in the stacking direction, a plurality of elastic bodies having elasticity and conductivity in the stacking direction and installed on the fixed metal plates, and a plurality of movable metal plates having a plate shape extending in the intersecting direction, supported by the fixed metal plates via the elastic bodies, and movable in the stacking direction. The fuel cell is configured to be attachable and detachable between a pair of the movable metal plates arranged adjacent to each other in the stacking direction, or between the fixed metal plate and the movable metal plate arranged adjacent to the fixed metal plate and supported by another fixed metal plate adjacent to the fixed metal plate via the elastic body.

Effects of the Invention

[0007] According to the fuel cell stack case of the present invention, the fuel cell can be exchanged easily and in a short time, and power can be generated even when a defective cell is removed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing the appearance of a fuel cell stack case 1 according to an embodiment of the present invention. Further, FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. In each of the drawings described below, the direction of arrow D1 indicates the stacking direction of the fuel cells 3, the direction of arrow D2 indicates the insertion / removal direction of the fuel cells 3, and arrow D3 indicates the direction orthogonal to the stacking direction D1 and the insertion / removal direction D2.

[0010] In FIGS. 1 and 2, the fuel cell stack case 1 of the present embodiment includes, for example, a case body 11, a plurality of fixed metal plates 12, a plurality of elastic bodies 13, a plurality of movable metal plates 14, and a cover member 15. In the present embodiment, the height direction (vertical direction) in the box-shaped fuel cell stack case 1 corresponds to the stacking direction D1, and an example in which each fuel cell 3 is stacked vertically in a flat state will be described. Note that, in the same manner as in the present embodiment, it is also possible to set the width direction (left-right direction) in the box-shaped fuel cell stack case as the stacking direction and arrange the fuel cells side by side left and right in a vertically placed state.

[0011] The case body 11 is, for example, an insulating housing formed in a box shape (hollow rectangular parallelepiped) using a resin material. The case body 11 has an opening 11A that opens in the intersecting directions (D2, D3) intersecting the stacking direction D1 of the fuel cells 3. The opening 11A in the present embodiment is formed in the front wall among the four side walls of the box-shaped case body 11, and each of the plurality of fuel cells 3 is inserted into and removed from the inside of the case body 11 through the opening 11A. Here, for the sake of simplicity of explanation, the number of fuel cells 3 stacked and housed in the fuel cell stack case 1 is set to two, but it is of course possible to stack and house three or more fuel cells 3 inside the case body 11.

[0012] The plurality of fixed metal plates 12 each have a plate shape that spreads in the intersecting directions (D2, D3) with respect to the stacking direction D1. Each fixed metal plate 12 is fixed inside the case body 11 at intervals in the stacking direction D1. In the present embodiment, three fixed metal plates 12 are arranged at substantially equal intervals in the height direction of the case body 11. Each of the upper, middle, and lower fixed metal plates 12 has its rear end and both left and right ends fitted into concave groove portions formed on the inner side surfaces of the side walls of the case body 11. The upper surface of the upper fixed metal plate 12 abuts against the lower surface of the upper wall of the case body 11, and the lower surface of the lower fixed metal plate 12 abuts against the upper surface of the lower wall of the case body 11. The inside of the case body 11 is divided into two upper and lower accommodation spaces by the three fixed metal plates 12 as described above.

[0013] Each of the plurality of elastic bodies 13 has elasticity and conductivity in the stacking direction D1. As the elastic body 13, for example, a compression coil spring, a leaf spring, or the like can be used. In the present embodiment, a compression coil spring made of metal or plated with metal is used as each elastic body 13, and one end portion in the expansion and contraction direction of each individual elastic body 13 is installed on the lower surface of the upper fixed metal plate 12, the upper surface or the lower surface of the middle fixed metal plate 12, or the upper surface of the lower fixed metal plate 12.

[0014] The plurality of movable metal plates 14 each have a plate shape that spreads in the crossing directions (D2, D3) with respect to the stacking direction D1. Each movable metal plate 14 is elastically supported by the upper, middle, or lower fixed metal plate 12 via a plurality of elastic bodies 13. In the present embodiment, a pair of movable metal plates 14 facing each other are arranged in the upper space partitioned by the case body 11 and the upper and middle fixed metal plates 12. Also, a pair of movable metal plates 14 facing each other are arranged in the lower space partitioned by the case body 11 and the middle and lower fixed metal plates 12. That is, four movable metal plates 14 are provided inside the case body 11 in the present embodiment.

[0015] On the upper surface of the movable metal plate 14 arranged on the upper side among the pair of movable metal plates 14 in the upper space, recesses are formed at positions corresponding to the respective elastic bodies 13 installed on the lower surface of the upper fixed metal plate 12. At the bottom portion of the recess, the other end portion in the expansion and contraction direction of the corresponding elastic body 13 is in pressure contact. Also, on the lower surface of the movable metal plate 14 arranged on the lower side among the pair of movable metal plates 14 in the upper space, recesses are formed at positions corresponding to the respective elastic bodies 13 installed on the upper surface of the middle fixed metal plate 12. At the bottom portion of the recess, the other end portion in the expansion and contraction direction of the corresponding elastic body 13 is in pressure contact.

[0016] On the upper surface of the movable metal plate 14 disposed above the pair of movable metal plates 14 in the lower space, recesses are formed at positions corresponding to the respective elastic bodies 13 provided on the lower surface of the middle fixed metal plate 12. At the bottom of the recess, the other end in the expansion and contraction direction of the corresponding elastic body 13 is in pressure contact. Also, on the lower surface of the movable metal plate 14 disposed below the pair of movable metal plates 14 in the lower space, recesses are formed at positions corresponding to the respective elastic bodies 13 provided on the upper surface of the lower fixed metal plate 12. At the bottom of the recess, the other end in the expansion and contraction direction of the corresponding elastic body 13 is in pressure contact.

[0017] Therefore, in each of the upper space and the lower space partitioned by the case body 11 and the respective fixed metal plates 12, the pair of movable metal plates 14 are movable in the expansion and contraction direction (lamination direction D1) of the elastic body 13, and a housing space for attaching and detaching the fuel cell stack 3 is formed between the lower surface of the upper movable metal plate 14 and the upper surface of the lower movable metal plate 14. In a state where the fuel cell stack 3 is attached in the housing space, the lower surface of the upper movable metal plate 14 and the upper surface of the lower movable metal plate 14 become surfaces that are in pressure contact with the fuel cell stack 3 (hereinafter referred to as "pressure contact surfaces with the fuel cell stack 3").

[0018] At the end (front end) of each movable metal plate 14 located on the side of the opening 11A of the case body 11, an inlet 14A for the fuel cell 3 is formed respectively. In the present embodiment, the inlet 14A of each movable metal plate 14 is formed, for example, by chamfering the corner portion on the pressure contact surface side with the fuel cell 3 at the front end of the movable metal plate 14 across the width direction (left - right direction). By providing such an inlet 14A in each movable metal plate 14, it becomes easier to guide the tip of the fuel cell 3 inserted into the case body 11 through the opening 11A inward of the case body 11. In the example of FIG. 2, the end (rear end) of each movable metal plate 14 on the side opposite to the opening 11A is also chamfered in the same manner as the above - mentioned inlet 14A. Since each movable metal plate 14 has a symmetric shape in the insertion and extraction direction (front - rear direction) of the fuel cell 3, it is possible to prevent the mistake of assembling the movable metal plate 14 in the reverse direction during the assembly work. However, it is also possible to omit the chamfered shapes at both the front and rear ends of each movable metal plate 14 as described above.

[0019] Regarding the movable metal plate 14 located on the lower side among the pair of movable metal plates 14 respectively arranged in the upper space and the lower space in the case body 11, a fitting portion 14B that fits with the fitting portion 37 formed on the fuel cell 3 is formed on the pressure contact surface (upper surface) with the fuel cell 3. The fitting portion 14B of the movable metal plate 14 in the present embodiment has a hemispherical concave surface, and the fitting portion 37 of the fuel cell 3 has a hemispherical convex surface. The arrangement of the fitting portion 37 and the fitting portion 14B will be described later.

[0020] The cover member 15 is provided at each end (front end) of each pair of the movable metal plates 14 described above, which is located on the opening 11A side of the case body 11 (FIG. 1). The cover member 15 covers at least a part of the location where the fuel cell 3 is inserted and removed in an openable and closable manner. In the present embodiment, the cover member 15 is provided so as to cover the intermediate portion in the width direction (left-right direction) of the inlet 14A of each movable metal plate 14 in an openable and closable manner. The cover member 15 has, for example, a strip-shaped shape extending in the vertical direction, the upper end portion is rotatably attached to the front end surface of the upper movable metal plate 14, and the lower end portion is formed in a claw shape that can be locked to the front end surface of the lower movable metal plate 14. The cover member 15 prevents the fuel cell 3 housed in the case body 11 from being displaced in the insertion and removal direction, and also serves as a mark for confirming the state of the cover member 15 at the replacement position when replacing a defective cell or the like.

[0021] Here, the fuel cell 3 stacked and housed in the fuel cell stack case 1 as described above will be described in detail with reference to FIGS. 3 and 4. FIG. 3 is a plan view showing a configuration example of the fuel cell 3 in the present embodiment. FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3.

[0022] As shown in FIGS. 3 and 4, the fuel cell 3 includes, for example, a single cell in which a pair of separators (electrodes) 31 sandwich a membrane electrode assembly (MEA) 32. The membrane electrode assembly 32 is composed of a catalyst layer, an electrolyte membrane, a gas diffusion layer (GDL), and the like. In the present embodiment, the outer shape of the fuel cell 3 is formed in a substantially rectangular shape in plan view. Here, an example in which the fuel cell 3 is formed of a single cell is described, but the fuel cell 3 may be formed by stacking a plurality of single cells. That is, the "fuel cell" of the present invention represents a unit (cell unit) composed of at least one single cell.

[0023] In FIG. 3, the fuel cell 3 has a hydrogen inlet 33A provided in the upper left portion, a hydrogen outlet 33B provided in the lower right portion, an air inlet 34A provided in the upper right portion, and an air outlet 34B provided in the lower left portion. Each of the hydrogen inlet 33A, the hydrogen outlet 33B, the air inlet 34A, and the air outlet 34B is formed so as to penetrate the fuel cell 3 in the thickness direction. Note that the arrow line in FIG. 4 represents the flow of hydrogen in the hydrogen outlet 33B.

[0024] The fuel cell 3 generates electricity by a chemical reaction between hydrogen supplied from the hydrogen inlet 33A and oxygen contained in the air supplied from the air inlet 34A within the MEA 32, and the electrical energy is taken out to the outside of the cell via the separator (electrode) 31. In FIG. 3, the central region surrounded by the broken line corresponds to the power generation portion (catalyst coating portion) 35 of the fuel cell 3. Each separator 31 is provided with a cell voltage measurement tab 36 extending outward from one end in the longitudinal direction (FIGS. 1 to 3).

[0025] The fuel cell 3 has a fitting portion 37 having the above-described hemispherical convex surface formed at a predetermined position on the outer surface of one separator 31. In the example of FIG. 3, the fitting portions 37 are arranged at four locations, i.e., the upper central portion, the lower central portion, the right central portion, and the left central portion on the outer surface of the separator 31. However, the arrangement of the fitting portions 37 is not limited to this.

[0026] In FIG. 3, the portion 38 surrounded by the two-dot chain line and hatched represents the projection of the preferable arrangement range of each elastic body 13 of the fuel cell stack case 1 onto the fuel cell 3 when viewed from the stacking direction D1 in a state where the fuel cell 3 is stacked and housed in the fuel cell stack case 1. Thus, it is preferable that each elastic body 13 of the fuel cell stack case 1 is arranged so as to overlap the peripheral portion of the fuel cell 3 avoiding the power generation portion 35.

[0027] At this time, if each elastic body 13 is arranged so as to overlap the four corner portions at the peripheral edge of the substantially rectangular fuel cell 3, the fuel cell 3 will be evenly pressed in the stacking direction D1 by the movable metal plate 14, so that the power generation performance will be enhanced. In the example of FIG. 3, since a hydrogen inlet 33A, a hydrogen outlet 33B, an air inlet 34A, and an air outlet 34B are provided at the four corner portions of the peripheral edge of the fuel cell 3, it is effective to arrange each elastic body 13 so as to overlap around these gas inlets and outlets. By arranging each elastic body 13 in this way, it becomes possible to prevent gas from leaking out from around the gas inlets and outlets while enhancing the power generation performance. Further, if each elastic body 13 is arranged near the outer periphery of the power generation portion 35 of the fuel cell 3 along the periphery, the power generation portion 35 can be more evenly pressed by the movable metal plate 14, so that the power generation performance can be further enhanced.

[0028] Gas flow paths are formed at positions corresponding to the gas inlets and outlets (hydrogen inlet 33A, hydrogen outlet 33B, air inlet 34A, and air outlet 34B) of the fuel cell 3 as described above in each fixed metal plate 12 and each movable metal plate 14 of the fuel cell stack case 1.

[0029] FIG. 5 is an enlarged cross-sectional view for explaining the configuration around the gas flow path of the fixed metal plate 12 and the movable metal plate 14 in the present embodiment. The upper part of FIG. 5 shows the state before assembling the movable metal plate 14 to the fixed metal plate 12 provided with the elastic body 13. The middle part of FIG. 5 shows the state after assembling the movable metal plate 14 to the fixed metal plate 12. The lower part of FIG. 5 shows the state where the fuel cell 3 is inserted into the case body 11 and the movable metal plate 14 has moved downward.

[0030] As shown in Fig. 5, through-holes (gas flow paths) 12A and 14C extending in the stacking direction D1 are formed in the fixed metal plate 12 and the movable metal plate 14 at positions corresponding to the gas inlets and outlets of the fuel cell 3, respectively. A thin-walled cylindrical tube 12B extending toward the through-hole 14C of the movable metal plate 14 is continuously provided in the through-hole 12A of the fixed metal plate 12. The diameter of the thin-walled cylindrical tube 12B is set to be slightly smaller than the diameter of the through-hole 14C of the movable metal plate 14. One end of the elastic body 13 is fixed to the periphery of the through-hole 12A of the fixed metal plate 12. A recess 14D is formed at a position corresponding to the elastic body 13 on the periphery of the through-hole 14C of the movable metal plate 14.

[0031] When assembling the movable metal plate 14 to the fixed metal plate 12 as described above, the thin-walled cylindrical tube 12B and the elastic body 13 on the fixed metal plate 12 side are aligned with the through-hole 14C and the recess 14D of the movable metal plate 14, and the movable metal plate 14 is brought closer to the fixed metal plate 12 (upper part of Fig. 5). When the other end of the elastic body 13 abuts against the bottom part of the recess 14D of the movable metal plate 14 and the elastic body 13 is compressed by the weight of the movable metal plate 14, the tip part of the thin-walled cylindrical tube 12B enters the inside of the through-hole 14C of the movable metal plate 14, and the through-hole 12A of the fixed metal plate 12 and the through-hole 14C of the movable metal plate 14 are in a communicating state via the thin-walled cylindrical tube 12B (middle part of Fig. 5). Then, the fuel cell 3 is inserted into the case body 11, the elastic body 13 is further compressed, the movable metal plate 14 moves downward, and the lower surface of the movable metal plate 14 approaches the upper surface of the fixed metal plate 12 (lower part of Fig. 5). In this state, the length of the thin-walled cylindrical tube 12B is designed so that the tip of the thin-walled cylindrical tube 12B is located inside the through-hole 14C of the movable metal plate 14 and does not protrude from the upper surface of the movable metal plate 14.

[0032] Next, each operation of attaching and detaching the fuel cell 3 in the fuel cell stack case 1 of the present embodiment will be described in detail with reference to FIGS. 2 and 6 to 8 described above. First, as shown in FIG. 6, in the fuel cell stack case 1 before the fuel cell 3 is attached, a pair of movable metal plates 14 arranged in the upper space within the case body 11 are in contact with each other by the elastic force of each elastic body 13. Also, a pair of movable metal plates 14 arranged in the lower space within the case body 11 are also in contact with each other by the elastic force of each elastic body 13.

[0033] With respect to the fuel cell stack case 1 in the state as described above, for the fuel cell 3, the end portion located on the side opposite to the cell voltage measurement tab 36 is inserted between the pair of movable metal plates 14 from the inlet ports 14A respectively formed in the pair of movable metal plates 14 (white arrow in FIG. 6). At this time, the cover member 15 of the fuel cell stack case 1 is in a state of being rotated upward so that the insertion and extraction portion of the fuel cell 3 is opened. Each movable metal plate 14 into which the tip end portion of the fuel cell 3 is inserted from the inlet port 14A moves in a direction away from each other vertically, and by this movement, each elastic body 13 is compressed. Then, when the tip end portion of the fuel cell 3 is inserted to the back of the case body 11, as shown in FIG. 2 described above, the fitting portion 37 of the fuel cell 3 and the fitted portion 14B of the movable metal plate 14 are fitted together, and thus the fuel cell 3 is attached to a predetermined position within the accommodation space.

[0034] When the fuel cell 3 is attached to a predetermined position within the accommodation space, as shown by the arrow a1 in FIG. 7, the cover member 15 is rotated downward and the claw-shaped portion at the tip is locked to the movable metal plate 14. Thereby, the insertion and extraction portion of the fuel cell 3 is closed by the cover member 15, and the movement of the fuel cell 3 in the insertion and extraction direction D2 is restricted.

[0035] As described above, each fuel cell 3 housed in the upper space and the lower space within the case body 11 is in a pressurized state (a state where surface pressure is applied), being evenly pressed in the stacking direction D1 by a pair of movable metal plates 14 that receive the elastic force of each compressed elastic body 13. Also, each fuel cell 3 is in a state of being electrically connected via the middle fixed metal plate 12 disposed between each of them and the elastic bodies 13 and the movable metal plates 14 disposed above and below it. Thereby, operation (power generation) of a fuel cell in which two fuel cells 3 are stacked becomes possible.

[0036] When a defect occurs in one of the two fuel cells 3 stacked and housed in the fuel cell stack case 1 (here, the fuel cell 3 attached to the lower space) and replacement becomes necessary, as shown by the arrow a2 in FIG. 7, the cover member 15 corresponding to the fuel cell 3 to be replaced is rotated upward, and the insertion / removal location of the fuel cell 3 is opened. Then, when a force is applied to the fuel cell 3 to be replaced in the direction of pulling it out from the case body 11, the fitting portion 37 of the fuel cell 3 disengages from the fitted portion 14B of the movable metal plate 14, and the fuel cell 3 is removed from the case body 11.

[0037] As shown in FIG. 8, each movable metal plate 14 from which the fuel cell 3 to be replaced has been removed is in a state where each elastic body 13 extends and moves in the direction of approaching each other vertically and comes into contact with each other. In such a state where the fuel cell 3 to be replaced has been removed, the normal fuel cell 3 in the upper space remains in a state of being pressurized by the pair of movable metal plates 14. Also, the lower space from which the defective fuel cell 3 has been removed is in a state where the middle and lower fixed metal plates 12 are electrically connected via the elastic bodies 13 and the pair of movable metal plates 14. For this reason, even in a state where the defective fuel cell 3 has been removed from the fuel cell stack case 1, operation (power generation) by the remaining normal fuel cells 3 is possible.

[0038] As described above, in the fuel cell stack case 1 of the present embodiment, each movable metal plate 14 is supported by the fixed metal plate 12 via the elastic body 13, and each fuel cell 3 is attached and detached between a pair of movable metal plates 14 arranged adjacent to each other in the stacking direction D1. According to such a fuel cell stack case 1, when a problem occurs in any of the fuel cells 3, the defective fuel cell 3 can be easily and quickly removed from the case body 11 and a new fuel cell 3 can be attached, so that the man-hours associated with the replacement of the fuel cell 3 can be significantly reduced. In addition, since it has a structure that does not affect the non-defective cells when replacing the defective fuel cell 3, the risk of overpressure associated with the reassembly of the fuel cell 3 can be eliminated. Furthermore, the surface pressure can be managed for each fuel cell 3, and a structure is realized in which unevenness in the surface pressure of each stacked fuel cell 3 is less likely to occur. In addition, even if a new fuel cell 3 is not attached to the empty space from which the defective fuel cell 3 has been removed, the fixed metal plate 12, the elastic body 13, and the movable metal plate 14 in the empty space are electrically connected, so that the fuel cell can be operated (generate electricity) by the remaining normal fuel cells 3.

[0039] Further, in the fuel cell stack case 1 of the present embodiment, each movable metal plate 14 has an inlet 14A. Thereby, the insertion and extraction of the fuel cell 3 can be easily performed, so that the time associated with the replacement of the fuel cell 3 can be further shortened.

[0040] In addition, in the fuel cell stack case 1 of the present embodiment, the movable metal plate 14 has a fitted portion 14B, and the position of the fuel cell 3 is determined by fitting the fitting portion 37 formed on the fuel cell 3 and the fitted portion 14B. As a result, displacement of the fuel cell 3 is less likely to occur, so that a more stable surface pressure can be applied to each fuel cell 3. At this time, if the fitted portion 14B of the movable metal plate 14 is formed in a concave shape, the pair of movable metal plates 14 come into surface contact with each other when the fuel cell 3 is removed, so that the electrical connection between the movable metal plates 14 can be stabilized. Further, if the fitted portion 14B of the movable metal plate 14 has a hemispherical concave surface and the fitting portion 37 of the fuel cell 3 has a hemispherical convex surface, the area where the fuel cell 3 slides with the movable metal plate 14 during insertion and removal decreases, so that problems of the fuel cell 3 caused by insertion and removal can be suppressed. In addition, if the fitting portion 37 of the fuel cell 3 is formed only on one separator 31 as in the present embodiment, it is also possible to prevent the mistake of inserting the fuel cell 3 into the case body 11 in the wrong vertical direction.

[0041] In addition, in the fuel cell stack case 1 of the present embodiment, each elastic body 13 is installed at the peripheral edge of the fixed metal plate 12. As a result, the fuel cell 3 is evenly pressed in the stacking direction D1 by the movable metal plate 14 via each elastic body 13, so that the power generation performance can be improved.

[0042] In addition, in the fuel cell stack case 1 of the present embodiment, a cover member 15 is provided to cover at least a part of the portion where the fuel cell 3 is inserted and removed in an openable and closable manner. As a result, displacement of the fuel cell 3 in the insertion and removal direction housed in the case body 11 can be reliably prevented. In addition, when replacing a defective cell, the state of the cover member 15 can be used as a mark to confirm the replacement position, so that the man-hours associated with replacing the defective cell can be reduced.

[0043] The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications and changes are possible based on the technical idea of the present invention. Hereinafter, several modification examples related to the above-described embodiments will be described.

[0044] FIG. 9 is a cross-sectional view showing a modification example of the arrangement of the fixed metal plate 12 and the movable metal plate 14 related to the above-described embodiment. In the above-described embodiment, a configuration example in which a pair of movable metal plates 14 are arranged between the upper and middle fixed metal plates 12 and a pair of movable metal plates 14 are arranged between the middle and lower fixed metal plates 12 has been described. On the other hand, in the modification example shown in FIG. 9, one movable metal plate 14 is arranged between the upper and middle fixed metal plates 12 and between the middle and lower fixed metal plates 12, respectively.

[0045] Specifically, in the arrangement shown in the upper left of FIG. 9, the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the lower surface of the upper fixed metal plate 12, and the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the lower surface of the middle fixed metal plate 12. In such an arrangement, the fuel cell 3 is accommodated between the lower surface of the upper movable metal plate 14 and the upper surface of the middle fixed metal plate 12, and the fuel cell 3 is accommodated between the lower surface of the lower movable metal plate 14 and the upper surface of the lower fixed metal plate 12.

[0046] In the arrangement shown in the upper right of FIG. 9, the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the upper surface of the middle fixed metal plate 12, and the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the upper surface of the lower fixed metal plate 12. In such an arrangement, the fuel cell 3 is accommodated between the lower surface of the upper fixed metal plate 12 and the upper surface of the upper movable metal plate 14, and the fuel cell 3 is accommodated between the lower surface of the middle fixed metal plate 12 and the upper surface of the lower movable metal plate 14.

[0047] In the arrangement shown at the lower left of FIG. 9, the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the upper surface of the middle fixed metal plate 12, and the movable metal plate 14 is also elastically supported via a plurality of elastic bodies 13 installed on the lower surface of the middle fixed metal plate 12. In such an arrangement, the fuel cell 3 is accommodated between the lower surface of the upper fixed metal plate 12 and the upper surface of the upper movable metal plate 14, and the fuel cell 3 is also accommodated between the lower surface of the lower movable metal plate 14 and the upper surface of the lower fixed metal plate 12.

[0048] In the arrangement shown at the lower right of FIG. 9, the movable metal plate 14 is elastically supported via a plurality of elastic bodies 13 installed on the lower surface of the upper fixed metal plate 12, and the movable metal plate 14 is also elastically supported via a plurality of elastic bodies 13 installed on the upper surface of the lower fixed metal plate 12. In such an arrangement, the fuel cell 3 is accommodated between the lower surface of the upper movable metal plate 14 and the upper surface of the middle fixed metal plate 12, and the fuel cell 3 is also accommodated between the lower surface of the middle fixed metal plate 12 and the upper surface of the lower movable metal plate 14.

[0049] With the arrangement of the fixed metal plate 12 and the movable metal plate 14 in the above-described modification, in addition to obtaining the same operational effects as in the case of the above-described embodiment, it becomes possible to simplify the configuration of the fuel cell stack case 1 and reduce the cost.

[0050] FIG. 10 is an enlarged cross-sectional view showing a modification of the shapes of the fitting portion 37 and the fitted portion 14B related to the above-described embodiment. Further, FIG. 11 is a plan view for explaining the arrangement of the fitting portion 37 corresponding to the modification of FIG. 10.

[0051] In the above-described embodiment, an example in which the fitting portion 14B of the movable metal plate 14 has a hemispherical concave surface and the fitting portion 37 of the fuel cell 3 has a hemispherical convex surface has been described. On the other hand, in the modification shown in FIG. 10, the fitting portion 14B of the movable metal plate 14 has first inner surfaces 14B1, 14B1' and second inner surfaces 14B2, 14B2'. The first inner surfaces 14B1, 14B1' extend in a direction orthogonal to the pressure contact surface (plate surface) with the fuel cell 3 in the movable metal plate 14. The second inner surfaces 14B2, 14B2' extend from the end portions located on the opposite side of the pressure contact surface in the orthogonal direction in the first inner surfaces 14B1, 14B1' so as to approach the pressure contact surface toward the side of the opening 11A of the case body 11. Further, the fitting portion 37 of the fuel cell 3 has first outer surfaces 371, 371' corresponding to the shapes of the first inner surfaces 14B1, 14B1' and second outer surfaces 372, 372' corresponding to the shapes of the second inner surfaces 14B2, 14B2'.

[0052] Specifically, in the example on the left side of FIG. 10, the fitting portion 14B of the movable metal plate 14 is formed in a concave shape obtained by dividing a sphere into four parts, and the fitting portion 37 of the fuel cell 3 is formed in a convex shape obtained by dividing a sphere into four parts. That is, the first inner surface 14B1 of the fitting portion 14B and the first outer surface 371 of the fitting portion 37 correspond to the cut surface when a sphere is divided into four parts, and the second inner surface 14B2 of the fitting portion 14B and the second outer surface 372 of the fitting portion 37 correspond to the divided spherical surface.

[0053] In the example on the right side of FIG. 10, the fitting portion 14B of the movable metal plate 14 is formed in a concave shape having a right-angled triangle in cross section, and the fitting portion 37 of the fuel cell 3 is formed in a convex shape having a right-angled triangle in cross section. That is, the first inner surface 14B1' of the fitting portion 14B and the first outer surface 371' of the fitting portion 37 correspond to the surface including one side sandwiching the right angle in the right-angled triangle, and the second inner surface 14B2' of the fitting portion 14B and the second outer surface 372' of the fitting portion 37 correspond to the surface including the hypotenuse of the right-angled triangle.

[0054] In the modification of FIG. 10 as described above, when the fuel cell 3 is inserted into the case body 11, the first outer surfaces 371, 371' of the fitting portion 37 abut against the first inner surfaces 14B1, 14B1' of the fitted portion 14B, thereby reliably preventing the fuel cell 3 from moving inward in the case body 11. Therefore, it is possible to avoid inserting the fuel cell 3 too far into the back side. When applying the shapes of the fitting portion 37 and the fitted portion 14B according to such a modification, as shown by the dashed-dotted line in FIG. 11, each fitting portion 37 is arranged so as not to be aligned in a straight line with respect to the insertion / removal direction D2 of the fuel cell 3, that is, each fitting portion 37 needs to be arranged so as to be shifted in the width direction D3 orthogonal to the insertion / removal direction D2.

[0055] FIG. 12 is a side view showing a modification of the cover member 15 related to the above-described embodiment. In the above-described embodiment, an example in which the cover member 15 rotates about one end and the other end is locked to the movable metal plate 14 has been described. On the other hand, in the modification shown in FIG. 12, the cover member 15 has a shutter structure slidable in the stacking direction D1. When the cover member 15 is slid downward (arrow a1), the insertion / removal portion of the fuel cell 3 is closed by the cover member 15. Further, when the cover member 15 is slid upward (arrow a2), the insertion / removal portion of the fuel cell 3 is opened. Even when the cover member 15 according to such a modification is applied, the same effects as those in the above-described embodiment can be obtained.

Description of Reference Numerals

[0056] 1... Fuel cell stack case 11... Case body 11A... Opening 12... Fixed metal plate 12A... Through hole 12B... Thin-walled cylindrical tube 13... Elastic body 14... Movable metal plate 14A... Inlet 14B... Fitted portion 14C... Through hole 14D... Concave portion 15... Cover member 3…Fuel cell 31…Separator 32…Membrane electrode assembly (MEA) 33A…Hydrogen inlet 33B…Hydrogen outlet 34A…Air inlet 34B…Air outlet 35…Power generation part 36…Cell voltage measurement tab 37…Fitting part D1…Stacking direction D2, D3…Cross direction (insertion / extraction direction)

Claims

1. A fuel cell stack case for stackably accommodating a plurality of fuel cells in an exchangeable manner, comprising: a case body having an opening that opens in a direction intersecting the stacking direction of the fuel cells, and each of the fuel cells is inserted into and removed from the inside through the opening; a plurality of fixed metal plates having a plate shape extending in the intersecting direction and fixed inside the case body at intervals in the stacking direction; a plurality of elastic bodies having elasticity and conductivity in the stacking direction and installed on the fixed metal plates; a plurality of movable metal plates having a plate shape extending in the intersecting direction, supported by the fixed metal plates via the elastic bodies, and movable in the stacking direction; The fuel cell stack case is configured such that the fuel cell can be attached and detached between a pair of the movable metal plates arranged adjacent to each other in the stacking direction, or between the fixed metal plate and the movable metal plate arranged adjacent to the fixed metal plate and supported by another fixed metal plate via the elastic body.

2. The movable metal plate is formed at an end portion located on the side of the opening of the case body, and has an inlet for guiding the tip of the fuel cell inserted into the case body through the opening inward of the case body. The fuel cell stack case according to claim 1.

3. The movable metal plate and / or the fixed metal plate has a fitting portion formed on the plate surface that is in pressure contact with the fuel cell, and the position of the fuel cell on the plate surface is determined by fitting the fitting portion formed on the fuel cell and the fitting portion. The fuel cell stack case according to claim 1.

4. The fitting portion is formed in a concave shape. The fitting portion is formed in a convex shape corresponding to the concave shape. The fuel cell stack case according to claim 3.

5. The fitting portion has a hemispherical concave surface. The fitting portion has a hemispherical convex surface corresponding to the concave surface. The fuel cell stack case according to claim 4.

6. The fitting portion to be fitted has a first inner surface extending in a direction orthogonal to the plate surface, and a second inner surface extending from an end portion of the first inner surface located on the side opposite to the plate surface in the orthogonal direction so as to approach the plate surface as it goes toward the side of the opening of the case body. The fitting portion has a first outer surface corresponding to the shape of the first inner surface and a second outer surface corresponding to the shape of the second inner surface. The fuel cell stack case according to claim 4, characterized in that.

7. The fuel cell stack case according to claim 1, characterized in that the elastic body is installed at a peripheral portion of the fixed metal plate.

8. The fuel cell stack case according to claim 1, further comprising a cover member provided at an end portion of the movable metal plate and / or the fixed metal plate located on the side of the opening of the case body, and capable of opening and closing at least a part of a portion where each of the fuel cells is inserted and removed.

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