Load detection apparatus for fuel cell stack

Abstract

To provide a load detection apparatus capable of appropriately detecting a load applied to the entirety of power generation cells.SOLUTION: A load detection apparatus 1 for a fuel cell stack 10 includes: pressing means 72 capable of pressing the fuel cell stack 10 along a stacking direction 101; first load detection means 76 that is provided above the fuel cell stack 10, and when the pressing means 72 presses the fuel cell stack 10, detects a load of the fuel cell stack 10; and second load detection means 77 that is provided below the fuel cell stack 10, and when the pressing means 72 presses the fuel cell stack 10, detects a load of the fuel cell stack 10.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a load detection device for a fuel cell stack including a laminate in which a plurality of power generation cells are stacked.

Background Art

[0002] A polymer electrolyte fuel cell includes an electrolyte membrane / electrode structure (MEA). Electrodes are provided on both sides of the polymer electrolyte membrane of the electrolyte membrane / electrode structure. A seal member is provided on the outer periphery of the electrolyte membrane / electrode structure. The seal member is a member for preventing leakage of fuel gas, refrigerant, and the like. The electrolyte membrane / electrode structure is sandwiched between separators to constitute a power generation cell. The power generation cells are stacked in a number required to obtain a desired voltage to constitute a laminate. The laminate is used in the form of a fuel cell stack to which an end plate or the like is attached.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, heretofore, in the process of stacking power generation cells to form a laminate, a technique for appropriately detecting the load applied to the entire power generation cell has not been proposed. Therefore, there is a problem that it is difficult to find appropriate load conditions.

[0005] An object of the present invention is to provide a load detection device capable of appropriately detecting the load applied to the entire power generation cell.

Means for Solving the Problems

[0006] The load detection device for a fuel cell stack of the present invention is a load detection device for a fuel cell stack for manufacturing a fuel cell stack, and includes pressing means capable of pressing the fuel cell stack along the stacking direction, a first load detection means provided on the upper part of the fuel cell stack for detecting the load of the fuel cell stack when the fuel cell stack is pressed by the pressing means, and a second load detection means provided on the lower part of the fuel cell stack for detecting the load of the fuel cell stack when the fuel cell stack is pressed by the pressing means.

[0007] According to the above load detection device, it is possible to provide a load detection device capable of appropriately detecting the load applied to the entire power generation cell.

[0008] The first load detection means and the second load detection means may each include two or more load cells.

[0009] According to the above load detection device, it is possible to detect the loads applied to different parts of the power generation cell.

[0010] The first load detection means and the second load detection means each include a movable plate having one surface in contact with the load cell and the other surface in contact with the fuel cell stack. The movable plate is divided into two or more parts in a plan view. When the parts are regarded as partial plates, the partial plates included in the first load detection means and the partial plates included in the second load detection means are arranged at the same position in a plan view, and the load cells included in the first load detection means and the load cells included in the second load detection means may be attached at the same position in a plan view.

[0011] According to the above load detection device, it is possible to accurately detect the loads applied to different parts of the power generation cell.

[0012] The partial plate may include a first partial plate located at the center of the movable plate in a plan view, and a second partial plate covering the outer periphery of the first partial plate in the plan view.

[0013] According to the load detection device described above, the load applied to different functional parts of the power generation cell can be accurately detected.

[0014] The fuel cell stack includes a power generation cell, the power generation cell includes an electrolyte membrane / electrode structure and a resin frame member, the first partial plate is located at a portion where the electrolyte membrane / electrode structures are stacked in a plan view, and the second partial plate may be located at a portion where the resin frame members are stacked in the plan view.

[0015] According to the load detection device described above, the load applied to the portion where the electrodes are stacked and the portion where the frames are stacked in the power generation cell can be accurately detected.

Effect of the Invention

[0016] According to the present invention, a load detection device capable of appropriately detecting the load applied to the entire power generation cell can be provided.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Mode for Carrying Out the Invention

[0018] (Fuel cell stack) A load detection device 1 of a fuel cell stack 10 according to an embodiment of the present invention will be described. Before describing the load detection device 1, the fuel cell stack 10 will be described. FIG. 1 is a perspective view of the fuel cell stack 10 of the present embodiment. The fuel cell stack 10 includes a laminate 14. The laminate 14 includes a plurality of stacked power generation cells 12. In FIG. 1, a first direction 101, a second direction 102, and a third direction 103 are shown. The first direction 101, the second direction 102, and the third direction 103 are orthogonal to each other. The first direction 101 is the direction in which the power generation cells 12 are stacked. The first direction 101 is referred to as the stacking direction 101. Also, looking in the first direction 101 is referred to as a plan view.

[0019] At one end of the laminate 14 in the stacking direction 101, a first insulator 18 and a first end plate 21 are arranged in this order toward the outside of the laminate 14. At the other end of the laminate 14 in the stacking direction 101, a second insulator 19 and a second end plate 22 are arranged in this order toward the outside of the laminate 14. The material of the insulator is, for example, an insulating material such as polycarbonate and phenolic resin. A spacer may be arranged between the laminate 14 and the end plate.

[0020] As shown in FIG. 1, the shape of the end plate is rectangular. A connecting bar 24 is arranged between the opposing sides of the first end plate 21 and the second end plate 22. Both ends of the connecting bar 24 are fixed to each end plate with bolts 26. By fixing both end plates via the connecting bar 24, the distance between the first end plate 21 and the second end plate 22 is fixed. Also, a fastening load in the stacking direction 101 is applied to each power generation cell 12.

[0021] Referring to FIG. 2, the configuration of the power generation cell 12 and the laminate 14 will be described. FIG. 2 is a diagram showing the load detection device 1 of the fuel cell stack 10 of the present embodiment. FIG. 2 shows a state in which the fuel cell stack 10 including the laminate 14 and the like is installed in the load detection device 1.

[0022] (Power generation cell) As shown in FIG. 2, the power generation cell 12 has a structure in which an electrolyte membrane / electrode structure 30 is sandwiched between conductive separators 32. A resin frame member 28 is provided around the electrolyte membrane / electrode structure 30.

[0023] The electrolyte membrane / electrode structure 30 includes a solid polymer electrolyte membrane 31. The resin frame member 28 surrounds the outer periphery of the solid polymer electrolyte membrane 31. The resin frame member 28 has a frame shape in plan view.

[0024] The separator 32 is formed of a conductive material such as metal and carbon. A seal member 34 is provided so as to surround the outer peripheral end of the separator 32. The seal member 34 is formed of a material having elasticity such as rubber.

[0025] (Laminate) A laminate obtained by laminating a plurality of power generation cells 12 is referred to as a laminate 14. (Seal laminate portion) A seal laminate portion 40 is formed at the outer edge of the laminate 14. The seal laminate portion 40 is a portion where the seal members 34 are laminated.

[0026] (Electrode laminate portion) An electrode laminate portion 41 is formed inside the seal laminate portion 40 in the laminate 14. The electrode laminate portion 41 is a portion where the electrolyte membrane / electrode structures 30 are laminated.

[0027] (Frame laminate portion) A frame laminate portion 42 is formed between the seal laminate portion 40 and the electrode laminate portion 41. The frame laminate portion 42 is a portion where the resin frame members 28 are laminated.

[0028] (Load Detection Device for Fuel Cell Stack) Referring to FIG. 2, the load detection device 1 for the fuel cell stack 10 will be described. The load detection device 1 mainly includes a pressing means 72, a control unit 78, a pressing plate 81, a first load detection means 76, a second load detection means 77, and a holding base 80. As shown in FIG. 2, in the stacking direction 101, the direction indicated by the arrow 104 is defined as the upward direction 104. In the stacking direction 101, the direction indicated by the arrow 105 is defined as the downward direction 105. The holding base 80 is arranged in the downward direction 105 in the load detection device 1. The pressing plate 81 is arranged in the upward direction 104 in the load detection device 1. An object to be pressed, which is arranged between the holding base 80 and the pressing plate 81 of the load detection device 1 and is pressed, is referred to as a pressing object 5. In the example shown in FIG. 2, the pressing object 5 is the fuel cell stack 10. The pressing object 5 is not limited to the fuel cell stack 10. The pressing object 5 can be, for example, a laminate 14 or the like.

[0029] (Pressing Means) The pressing means 72 presses the pressing object 5 in the downward direction 105 by bringing the pressing plate 81 closer to the holding base 80. The downward direction 105 is referred to as the pressing direction. The pressing means 72 can apply a load to the pressing object 5. The pressing means 72 can be, for example, a press mechanism such as a servo press.

[0030] (Pressing Plate) The pressing plate 81 is a part that applies a load to the pressing object 5 by being pressed by the pressing means 72. The holding base 80 is a part where the pressing object 5 is installed. The holding base 80 includes a base 83 and an arrangement jig 84. The arrangement jig 84 is arranged between the base 83 and the pressing object 5. The arrangement jig 84 has a shape that can stably arrange the first end plate 21 in a predetermined direction, for example.

[0031] The load detection device 1 of this embodiment includes two load detection means. One load detection means is the first load detection means 76, and the other load detection means is the second load detection means 77. The first load detection means 76 is arranged in the upward direction 104 of the object 5 to be pressed in the stacking direction 101. The second load detection means 77 is arranged in the downward direction 105 of the object 5 to be pressed in the stacking direction 101.

[0032] (The first load detection means) The first load detection means 76 includes a first fixing member 60, a movable plate 50, and a load cell 90.

[0033] (The first fixing member) The first fixing member 60 is fixed to the lower surface 82 of the pressing plate 81. The lower surface 82 of the pressing plate 81 is the surface of the pressing plate 81 facing the object 5 to be pressed. The first fixing member 60 includes an outer frame portion 61 and a recess 62. The outer frame portion 61 is a portion extending downward 105 from the lower surface 82 of the pressing plate 81 at the outer peripheral portion of the first fixing member 60. The outer frame portion 61 is arranged at a position corresponding to the seal lamination portion 40 of the laminate 14 when the object 5 to be pressed includes the laminate 14. The recess 62 is a portion surrounded by the outer periphery in the outer frame portion 61.

[0034] (The movable plate) The movable plate 50 is a plate-like member movable in the stacking direction 101. One surface of the movable plate 50 is in contact with the object 5 to be pressed. The other surface of the movable plate 50 is in contact with the load cell 90.

[0035] (The load cell) The load cell 90 measures the load by being pushed into the movable plate 50. The load cell 90 is arranged between the first fixing member 60 and the movable plate 50 in the stacking direction 101. The load cell 90 is arranged in the recess 62 of the first fixing member 60. The load cell 90 is fixed to the lower surface 63 of the first fixing member 60 facing downward 105.

[0036] The outer frame portion 61 of the first fixing member 60 covers the outside of the movable plate 50. The outer frame portion 61 of the first fixing member 60 defines the movement of the movable plate 50 in the stacking direction 101.

[0037] (Second load detection means) In the load detection device 1 of the present embodiment, in addition to the first load detection means 76, a second load detection means 77 is arranged in the downward direction 105 of the object 5 to be pressed. The second load detection means 77 has the same configuration as the first load detection means 76. However, the second load detection means 77 is arranged in a direction in which the first load detection means 76 is turned upside down.

[0038] Specifically, as shown in FIG. 2, a second fixing member 65 is arranged on the holding table 80. The outer frame portion 66 of the second fixing member 65 has a convex shape facing upward 104. The concave portion 67 of the second fixing member 65 has a concave shape that opens upward 104. A load cell 90 is arranged in the concave portion 67. The lower surface of the movable plate 50 included in the second load detection means 77 is in contact with the load cell 90.

[0039] (Control unit) The control unit 78 is a part that controls the operation of the load detection device 1. The control unit 78 controls the pressing means 72 and adjusts the force for pressing the pressing plate 81 and the speed for moving the pressing plate 81. The load detected by the load cell 90 is input to the control unit 78.

[0040] In the load detection device 1 of the present embodiment, load detection means are arranged in the upward direction 104 and the downward direction 105 of the object 5 to be pressed. Therefore, compared with a load detection device in which the load detection means is arranged only in the upward direction 104, for example, the load applied to the object 5 to be pressed can be detected in detail.

[0041] Furthermore, the first load detection means 76 and the second load detection means 77 each include a plurality of load cells 90. Therefore, the load applied to the object 5 to be pressed can be detected in more detail.

[0042] (Partial plate) In the load detection device 1 of the present embodiment, the movable plate 50 is divided into two parts. As shown in FIG. 2, the movable plate 50 included in the first load detection means 76 is divided into a first upper partial plate 53 and a second upper partial plate 54. The movable plate 50 included in the second load detection means 77 is divided into a first lower partial plate 55 and a second lower partial plate 56. This will be described with reference to FIGS. 3A and 3B.

[0043] FIG. 3A is a diagram showing the first partial plate 51. FIG. 3B is a diagram showing the second partial plate 52. The movable plate 50 is divided into a first partial plate 51 and a second partial plate 52. That is, the movable plate 50 is formed by combining the first partial plate 51 and the second partial plate 52.

[0044] The first partial plate included in the first load detection means 76 is referred to as the first upper partial plate 53, and the first partial plate included in the second load detection means 77 is referred to as the first lower partial plate 55. The first upper partial plate 53 and the first lower partial plate 55 have the same shape at least in plan view.

[0045] Similarly, the second partial plate included in the first load detection means 76 is referred to as the second upper partial plate 54, and the second partial plate included in the second load detection means 77 is referred to as the second lower partial plate 56. The second upper partial plate 54 and the second lower partial plate 56 have the same shape at least in plan view.

[0046] (First partial plate) The first partial plate 51 is a plate located at the center of the movable plate 50 in plan view as shown in FIG. 3A. The first partial plate 51 has a rectangular shape in plan view.

[0047] (Second partial plate) As shown in FIG. 3B, the second partial plate 52 is a plate located on the outer periphery of the movable plate 50 in a plan view. The second partial plate 52 has a rectangular frame shape in a plan view. The second partial plate 52 has a shape that covers the outer periphery of the first partial plate 51 in a plan view.

[0048] The entire movable plate 50 is formed by arranging the first partial plate 51 within the frame of the second partial plate 52.

[0049] The first upper partial plate 53 and the first lower partial plate 55 are arranged so as to overlap in a plan view. Similarly, the second upper partial plate 54 and the second lower partial plate 56 are arranged so as to overlap in a plan view.

[0050] That is, the first upper partial plate 53 and the first lower partial plate 55 are arranged at the same position in a plan view. Also, the second upper partial plate 54 and the second lower partial plate 56 are arranged at the same position in a plan view.

[0051] Note that the number of partial plates when dividing the movable plate is not limited to two. The movable plate may be divided into three or more partial plates. Also, the shape of the partial plates in a plan view is not limited to the examples shown in FIGS. 3A and 3B.

[0052] (Load cell) The load cell 90 will be described. As described above, the load cell 90 includes two or more of the first load detection means 76 and the second load detection means 77, respectively. Also, the first partial plate 51 and the second partial plate 52 are each in contact with one or more load cells 90.

[0053] In the example shown in FIG. 2, at the position of the third direction 103 shown in FIG. 2 (at the position of the cross section shown in FIG. 2), the first load detection means 76 and the second load detection means 77 each include four load cells 90. The load cells 90 included in the first load detection means 76 are referred to as the first load cell 91, the second load cell 92, the third load cell 93, and the fourth load cell 94. These load cells 90 are arranged in order in the second direction 102.

[0054] Similarly, the load cells 90 included in the second load detection means 77 are referred to as the fifth load cell 95, the sixth load cell 96, the seventh load cell 97, and the eighth load cell 98. These load cells 90 are arranged in order in the second direction 102.

[0055] Note that FIG. 2 illustrates the load cells 90 arranged in the second direction 102 at a certain position in the third direction 103. A plurality of load cells 90 may be arranged in the third direction 103. That is, a plurality of load cells 90 may be arranged two-dimensionally on the fixing member.

[0056] (Partial plate and load cell) In the example shown in FIG. 2, the second load cell 92 and the third load cell 93 are in contact with the first upper partial plate 53. Also, the first load cell 91 and the fourth load cell 94 are in contact with the second upper partial plate 54.

[0057] Similarly, the sixth load cell 96 and the seventh load cell 97 are in contact with the first lower partial plate 55. Also, the fifth load cell 95 and the eighth load cell 98 are in contact with the second lower partial plate 56.

[0058] With such a configuration, the loads applied to the first upper partial plate 53, the second upper partial plate 54, the first lower partial plate 55, and the second lower partial plate 56 can be detected separately.

[0059] Note that the load applied to the first upper partial plate 53 can be the sum of the loads of the second load cell 92 and the third load cell 93. Also, the load applied to the second upper partial plate 54 can be the sum of the loads of the first load cell 91 and the fourth load cell 94. The same applies to the first lower partial plate 55 and the second lower partial plate 56.

[0060] A load detection example using the load detection device 1 of this embodiment will be described. FIG. 4A is a graph showing the detection result of the load on the first partial plate 51. FIG. 4B is a graph showing the detection result of the load on the second partial plate 52. The X-axis in FIGS. 4A and 4B indicates the thickness d (mm) of the fuel cell stack 10 as the object 5 to be pressed. The Y-axis in FIGS. 4A and 4B indicates the load W (kN) detected by the load cell 90.

[0061] The line CT in FIG. 4A indicates the load on the first upper partial plate 53, and the line CL in FIG. 4A indicates the load on the first lower partial plate 55. The line OT in FIG. 4B indicates the load on the second upper partial plate 54, and the line OL in FIG. 4B indicates the load on the second lower partial plate 56.

[0062] In the examples shown in FIGS. 4A and 4B, as shown in FIG. 4A, in the plan view detected by the first partial plate 51, the load on the central portion of the object 5 to be pressed is higher on the lower side (CL) than on the upper side (CT). On the other hand, as shown in FIG. 4B, in the plan view detected by the second partial plate 52, the load on the peripheral portion of the object 5 to be pressed is higher on the upper side (OT) than on the lower side (OL).

[0063] From these results, it is inferred that the object 5 to be pressed has a shape in which the peripheral portion bulges and the central portion is depressed.

[0064] Also, when the magnitude relationship between the upper and lower loads is opposite to the examples shown in FIGS. 4A and 4B, it is inferred that the object 5 to be pressed has a shape in which the central portion bulges and the peripheral portion is depressed.

[0065] Also, when the magnitude relationship of the loads on the upper side and the lower side is not different, it is presumed that the object 5 to be pressed has a flat shape.

[0066] In this way, by arranging the movable plate and the load cell on the upper side and the lower side, dividing the movable plate into partial plates, and enabling the load of each partial plate to be measured, the shape of the object 5 to be pressed and the load borne by each part of the object 5 to be pressed can be grasped. Thereby, the behavior prediction of the object 5 to be pressed during pressing can be made.

[0067] When the object 5 to be pressed is the fuel cell stack 10, the behavior during pressing of the entire fuel cell stack 10 or the entire laminate 14 included in the fuel cell stack 10 can be predicted. Also, when the object 5 to be pressed is the laminate 14, the behavior during pressing of the entire laminate 14 can be predicted.

[0068] (Position relationship with the electrode laminate part and the frame laminate part) In the load detection device 1 of the present embodiment, the first upper partial plate 53 and the first lower partial plate 55 are located at the electrode laminate part 41 in a plan view. On the other hand, the second upper partial plate 54 and the second lower partial plate 56 are located at the frame laminate part 42 in a plan view.

[0069] By arranging the first partial plate 51 and the second partial plate 52 at the positions as described above, the load applied to the electrode laminate part 41, which is the part where the electrolyte membrane / electrode structures 30 are laminated in the laminate 14, and the load applied to the frame laminate part 42, which is the part where the resin frame members 28 are laminated in the laminate 14, can be separately detected. Thereby, the load applied to each functional part of the power generation cell can be detected more accurately.

[0070] The embodiments of the present invention have been described above. The present invention is not limited to the above-described embodiments, and various changes, modifications, and combinations are possible.

Description of reference numerals

[0071] 1 Load detection device 5 Object to be pressed 10 Fuel cell stack 12 Power generation cell 14 Laminate 50 Movable plate 51 First partial plate 52 Second partial plate 53 First upper partial plate 54 Second upper partial plate 55 First lower partial plate 56 Second lower partial plate 60 First fixing member 65 Second fixing member 72 Pressing means 76 First load detection means 77 Second load detection means 90 Load cell

Claims

1. A load detection device for a fuel cell stack for manufacturing a fuel cell stack, comprising: pressing means capable of pressing the fuel cell stack along the stacking direction; first load detection means provided on the upper part of the fuel cell stack for detecting the load of the fuel cell stack when the fuel cell stack is pressed by the pressing means; second load detection means provided on the lower part of the fuel cell stack for detecting the load of the fuel cell stack when the fuel cell stack is pressed by the pressing means. A load detection device for a fuel cell stack having these components.

2. The load detection device for a fuel cell stack according to claim 1, wherein the first load detection means and the second load detection means each include two or more load cells.

3. The first load detection means and the second load detection means each include a movable plate having one surface in contact with the load cell and the other surface in contact with the fuel cell stack. The movable plate is divided into two or more parts in a plan view. When the parts are regarded as partial plates, the partial plates included in the first load detection means and the partial plates included in the second load detection means are arranged at the same position in a plan view. The load detection device for a fuel cell stack according to claim 2, wherein the load cells included in the first load detection means and the load cells included in the second load detection means are attached at the same position in a plan view.

4. The load detection device for a fuel cell stack according to claim 3, wherein the partial plate includes a first partial plate located at the center of the movable plate in a plan view and a second partial plate covering the outer periphery of the first partial plate in a plan view.

5. The fuel cell stack includes a power generation cell. The power generation cell includes an electrolyte membrane / electrode structure and a resin frame member. The first partial plate is located at a portion where the electrolyte membrane / electrode structures are stacked in a plan view. The load detection device for a fuel cell stack according to claim 4, wherein the second partial plate is located at a portion where the resin frame members are stacked in a plan view.

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