JP2010272263A - Vehicular fuel battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular fuel battery which has a simple structure and can improve impact resistance of a laminated body without increasing an on-vehicle space. <P>SOLUTION: The fuel battery 10 has tension shafts 18 fitted into a side face 14a of a laminated body 14 in a laminating direction and fastens end plates 16 so as to tighten the laminated body 14. The fuel battery 10 also has a connecting member 22 connecting center sections 20 of the tension shafts 18 in the laminating direction, and two corner sections farthest from the center sections 20, that is, corner sections of the fuel battery 10 on the side face 14a. Bending of the tension shafts 18 can be restrained at the time of collision of a vehicle since the connecting members 22 reinforce portions of the tension shafts 18 where rigidity is smaller, and at the same time, shift of unit cells 12 can also be restrained. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicular fuel cell mounted on a vehicle, and more particularly to an improvement in a structure for supporting a laminated body formed by laminating a plurality of unit cells.

  A fuel cell is a device that generates electricity by causing an electrochemical reaction between a fuel gas (hydrogen), which is a reaction gas, and an oxidizing gas (oxygen). In recent years, a polymer electrolyte fuel cell using a solid polymer as an electrolyte between two electrodes has been developed, and is expected as a power supply source for vehicles such as automobiles because of its excellent in-vehicle property.

  The fuel cell has a stacked body formed by stacking a plurality of unit cells. The unit cell includes a membrane electrode assembly in which a fuel electrode (hereinafter referred to as an anode) as one electrode, a polymer electrolyte membrane, and an air electrode (hereinafter referred to as a cathode) as the other electrode are sequentially laminated. The structure is sandwiched between two separators. A pair of end plates are provided at both ends of the stacked body in the stacking direction. A tension shaft extends in the stacking direction on the side surface of the stack in the stacking direction. The tension shaft fastens a pair of end plates so as to fasten the laminate from both ends of the laminate. As described above, the tension shaft tightens the stacked body in the stacking direction via the end plate, thereby suppressing the shift of the unit cells in the direction perpendicular to the stacking direction.

  The following Patent Document 1 includes a stack configured by stacking a plurality of cells, end plates provided at both ends of the stack, and a support portion that supports each end plate via a spring and a pressure plate. A fuel cell support is described. In addition, the fuel cell support body includes an intermediate plate disposed in the middle of the stack and provided with a connecting portion, two fixed portions that are positioned vertically below the stack and are disposed with the intermediate plate interposed therebetween in the stacking direction, It has a link which connects a connection part and each fixed part, respectively. As described above, the fixing portion and the link regulate the position of the intermediate plate, thereby suppressing the occurrence of stack deflection.

  Patent Document 2 listed below includes a power generation laminate, a pair of end plates provided at both ends of the power generation laminate, and a fastening rod that spans the pair of end plates and applies compressive stress to the power generation laminate in the stacking direction. An in-vehicle fuel cell stack is described. In this fuel cell stack, since the fastening rod is supported by the partition wall of the vehicle via the connecting portion, it is possible to restrict the movement of the power generation stack and to prevent the displacement between the power generation stacks. it can.

JP-A-2005-235406 JP 2008-290470 A

  In the conventional vehicle fuel cell, the tension shaft tightens the stacked body in the stacking direction, thereby suppressing the shift of the unit cells in the direction perpendicular to the stacking direction. However, when a strong impact is applied to the fuel cell in a direction crossing the stacking direction, such as when a vehicle collides, a large shearing force is generated inside the stack, and the tension shaft is bent by this shearing force and the unit cell. There was a problem that would shift.

  In order to improve the impact resistance of the fuel cell for a vehicle, an intermediate plate is provided at an intermediate position of the stack that bends most at the time of collision, as in the fuel cell support of Patent Document 1, and this intermediate plate is moved. It is conceivable to provide a new structure for regulation. However, there is a problem that the number of parts increases, and the cost and assembly man-hour increase.

  Moreover, it is conceivable to newly provide a structure that supports the fastening rod from the vehicle and reinforces the fastening rod, as in the on-vehicle fuel cell stack of Patent Document 2. However, there is a problem that the in-vehicle space of the fuel cell stack becomes large.

  Further, it is conceivable to increase the rigidity of the tension shaft of a conventional vehicle fuel cell. However, there is a problem that the weight of the tension shaft increases and the weight of the vehicle fuel cell itself increases.

  An object of the present invention is to provide a fuel cell for a vehicle that has a simple structure and can improve the impact resistance of a laminate without increasing the space for mounting on a vehicle.

  The present invention includes a laminated body constituted by laminating a plurality of unit cells, a pair of end plates provided at both ends of the laminated body in the laminating direction, and fitted to the side surfaces of the laminated body in the laminating direction, A vehicle fuel cell having a tension shaft that fastens the pair of end plates so as to clamp the stack, and a center portion of the tension shaft in the stacking direction and a corner of the fuel cell on the side surface, It has a connecting member which connects two corners most distant from the central part.

  In addition, the tension shaft has a first tension shaft and a second tension shaft that are provided on the side surface of the laminate so as to be spaced apart from each other, and the connecting member includes a central portion of the first tension shaft and a central portion thereof. A first connecting member that connects the two corresponding first corners, a central portion of the second tension shaft, and a second connecting member that connects the two second corners corresponding to the central portion. Can have.

  In addition, it is preferable that the first tension shaft and the second tension shaft are respectively provided on opposite sides of the side surface.

  The tension shaft further includes a third tension shaft between the first tension shaft and the second tension shaft, and the connecting member includes a central portion of the third tension shaft, first and second corner portions, and A third connecting member for connecting the two.

  In addition, each connecting member can be strip-shaped.

  Further, the first and second connecting members and the third connecting member can be merged and integrated on the way to the first and second corners.

  Moreover, it is preferable that the width | variety of the part which the 1st and 2nd connection member and the 3rd connection part integrated is larger than the width | variety of 1st and 2nd connection members other than the part.

  Moreover, it is preferable that the ratio of the width of the integrated part to the widths of the first and second connecting members other than the part is 2: 1.

  Further, it is preferable that the corner portion is an end portion of the tension shaft in the stacking direction.

  According to the vehicle fuel cell of the present invention, it is possible to improve the impact resistance of the laminated body with a simple structure and without increasing the in-vehicle space.

It is a figure which shows the structure of the fuel cell for vehicles of this embodiment. It is sectional drawing by the AA line of FIG. It is a figure which shows the structure of the fuel cell for vehicles of another this embodiment. It is sectional drawing by the BB line of FIG.

  Hereinafter, embodiments of a fuel cell for a vehicle according to the present invention will be described with reference to the drawings. As an example, a vehicle fuel cell mounted on a vehicle so that the stacking direction of unit cells is in the vehicle width direction will be described, and the configuration of the vehicle fuel cell will be described. The present invention is not limited to the vehicle fuel cell mounted on the vehicle so that the unit cell stacking direction and the vehicle width direction match, and other directions, for example, the stacking direction and the vehicle traveling direction match. Thus, the present invention can also be applied to a vehicle fuel cell mounted on a vehicle.

  FIG. 1 is a diagram showing a configuration of a vehicle fuel cell (hereinafter simply referred to as a fuel cell) 10 of the present embodiment, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The fuel cell 10 includes a stacked body 14 configured by stacking a plurality of unit cells 12. Although not shown, the unit cell 12 has a structure in which a membrane electrode assembly in which an anode as one electrode, a polymer electrolyte membrane, and a cathode as the other electrode are sequentially stacked is sandwiched by two separators. is there.

  The fuel cell 10 has a pair of end plates 16 provided at both ends of the stacked body 14 in the stacking direction. The end plate 16 is made of metal, for example, stainless steel. The end plate 16 is provided with an opening (not shown) for supplying fuel gas, oxidant gas, and cooling medium to the laminate 14, and exhaust fuel gas, exhaust oxidant gas, and cooling medium are discharged from the laminate 14. Opening (not shown) is formed. The end plate 16 is formed with a bolt hole (not shown) for fastening a tension shaft 18 described later.

  Further, the fuel cell 10 includes a tension shaft 18 that extends in the stacking direction on the side surface 14a of the stack 14 in the stacking direction. The tension shaft 18 is made of metal, for example, carbon steel, stainless steel, or a composite material combining these. The tension shaft 18 is fixed to the end plate 16. Specifically, both ends of the tension shaft 18 are fastened to the end plate 16 via bolts (not shown). By this fastening, the end plate 16 presses the laminated body 14 from both ends of the laminated body 14 with a predetermined pressure to bring the unit cells 12 into close contact with each other and suppresses the deviation between the unit cells 12.

  The tension shafts 18 are respectively provided on opposite sides of the side surface 14a, and are provided so as to fit on the side surface 14a, as shown in FIG. When the tension shaft 18 is fitted to the side surface 14a, a part of the side surface 14 is formed to be recessed along the stacking direction, and the tension shaft 18 is fitted here. With this configuration, the stacked body 14 and the tension shaft 18 are in contact with each other in a direction perpendicular to the stacking direction. That is, in the present embodiment, the laminate 14 and the tension shaft 18 abut on each other in the vehicle traveling direction or in the opposite direction. Therefore, the tension shaft 18 can regulate the movement of the moving body 14 in these directions caused by the vibration of the vehicle, that is, the displacement between the unit cells 12.

  As shown in FIG. 2, the tension shaft 18 has a square pipe shape in consideration of weight reduction, and the inside thereof is hollow. The tension shaft 18 is not limited to a square pipe shape, and may be a round pipe shape, or the inside may be solid.

  As described above in the prior art, in a conventional fuel cell, when a strong impact is applied to the fuel cell in a direction crossing the stacking direction, such as at the time of a vehicle collision, a large shear force is generated inside the stack, The shearing force causes the tension shaft to bend and deform, and the unit cell is displaced.

  In order to solve this problem, in the present embodiment, the central portion 20 of the tension shaft 18 in the stacking direction and the corners of the fuel cell 10 on the side surface 14a, the two corners farthest from the central portion 20. It has the connection member 22 which connects a part, It is characterized by the above-mentioned. The corner of this embodiment is the end 24 of the tension shaft 18 in the stacking direction. However, the present invention is not limited to this, and the corner may be the end of the end plate 16.

  The connecting member 22 is made of metal, and is fixed to the central portion 20 and the end portion 24 of the tension shaft 18 by, for example, welding. The connecting member 22 has a flat plate shape, and specifically has a belt shape having a predetermined width t1. The connecting member 22 is not limited to a flat plate shape, and may have another shape, for example, a rod shape.

  The connecting member 22 includes a first connecting member 22a and a second connecting member 22b. The first connecting member 22a is provided so as to connect the central portion 20 of the tension shaft 18 on the vehicle traveling direction side and the end portions 24 of the tension shaft 18 on the opposite side in the vehicle traveling direction. The second connecting member 22b is provided so as to connect the central portion 20 of the tension shaft 18 on the side opposite to the vehicle traveling direction and the end portions 24 of the tension shaft 18 in the vehicle traveling direction. As shown in FIG. 1, the first and second connecting members 22 a and 22 b are each V-shaped, and are integrated in a region where they intersect.

  With such a configuration, when a strong impact is applied to the fuel cell 10 in a direction crossing the stacking direction at the time of a vehicle collision or the like, the bending of the tension shaft 18 can be suppressed. Specifically, the region in which the tension shaft 18 is most deformed by the impact of the inertial mass of the laminate 14 due to the impact, that is, the most deflected region is the central portion 20, and conversely, the region that is least deformed. That is, the regions that are least bent are the end portions 24. That is, the central portion 20 of the tension shaft 18 has the lowest rigidity, and each end portion 24 has the highest rigidity. Therefore, the connecting member 22 connects the central portion 20 that is the most bent region of the one tension shaft 18 and each end portion 24 that is the least bent region of the other tension shaft 18, and has a rigidity. Reinforce the small central part 20. Thus, for example, even when the laminated body 14 tries to move in the vehicle traveling direction and a force is applied to the tension shaft 18 on the vehicle traveling direction side at the time of the frontal collision of the vehicle, The bending of the tension shaft 18 is suppressed because the bending region is reinforced by being connected to each end 24 (the least bending region) of the other tension shaft 18 via the connecting member 22a. In the case of a rear collision, the connecting member 22b similarly suppresses the bending of the tension shaft 18 on the opposite side in the vehicle traveling direction.

  Therefore, only by adding a simple structure of the connecting member 22 from the configuration of the conventional fuel cell, it is possible to suppress the deflection of the tension shaft 18 at the time of a vehicle collision and to suppress the deviation of the unit cell 12, and as a result. As a result, the impact resistance of the laminate 14 can be improved.

  In the present embodiment, the case where the tension shaft 18 is provided on each of the opposing sides of the side surface 14a has been described, but the present invention is not limited to this configuration. If the tension shaft 18 is provided on the side surface 14a with a space between each other, the tension shaft 18 may be provided on the inner side of the side of the side surface 14a.

  In this embodiment, although the case where the 1st and 2nd connection members 22a and 22b were each V-shaped was demonstrated, it is not limited to this structure. The connecting member 22 connects the central portion 20 of one tension shaft 18 and one end portion 24 of the other tension shaft 18 or the end portion of the end plate 16 outside the end portion 24 in the stacking direction. It may be provided as follows. Even with this configuration, bending of one tension shaft 18 can be suppressed.

  Next, another embodiment of the fuel cell 10 will be described with reference to the drawings. FIG. 3 is a diagram showing a configuration of the fuel cell 10 according to another aspect, and FIG. 4 is a cross-sectional view taken along the line BB of FIG. In addition, the same code | symbol is attached | subjected about the same component as the said embodiment, and detailed description is abbreviate | omitted.

  The fuel cell 10 of this embodiment further includes a tension shaft 18 between the tension shafts 18 in addition to the tension shafts 18 provided on opposite sides of the side surface 14a. The tension shaft 18 is provided at the center of the side surface 14 a and is fixed to the end plate 16. Specifically, both ends of the tension shaft 18 are fastened to the end plate 16 via bolts (not shown). As shown in FIG. 4, the tension shaft 18 provided at the center of the side surface 14 a has a rectangular pipe shape and is hollow inside, as is the case with the tension shaft 18 provided on both sides. However, the tension shaft 18 provided in the center of the side surface 14 a is required to have higher rigidity. Therefore, the hollow portion of the tension shaft 18 is formed smaller than that of the other tension shafts 18.

  In addition to the first connecting member 22a and the second connecting member 22b, the connecting member 22 includes a central portion 20 of the tension shaft 18 provided in the center of the side surface 14a and a total of four tension shafts 18 provided on both sides. The third connecting member 22c is connected to each of the end portions 24.

  The third connecting member 22c of the present embodiment joins and is integrated with the first and second connecting members 22a and 22b on the way to the end portions 24. By integrating the connecting members 22a, 22b, and 22c, the number of parts can be reduced, and the number of assembly steps can be reduced. However, the present invention is not limited to this configuration, and the third connecting member 22c and the first and second connecting members 22a and 22b may be provided separately.

  Further, the width t2 of the portion where the first and second connecting members 22a, 22b and the third connecting member 22c are integrated is formed larger than the width t1 of the first and second connecting members 22a, 22b other than this portion. The Specifically, the ratio between the width t2 and the width t1 is preferably 2: 1. By forming the width t2 of the integrated portion larger than the width t1 of the other portions, the integrated portion is made up of the first or second connecting member 22a, 22b and the third connecting member 22c. It is possible to allow the total reaction force received from the central portions 20 to be connected to each other.

  As shown in FIG. 3, the width of the third connecting member 22c in the central portion 20 region of the tension shaft 18 provided in the center of the side surface 14a is the same as the first and second connecting members in the other central portion 20 regions. It is formed larger than the width of 22a, 22b. This prevents the strain generated in the third connecting member 22c when the tension shaft 18 provided at the center of the side surface 14a and the third connecting member 22c are fixed to each other by welding. It is to do.

  Moreover, as shown in FIG. 3, a hole 26 is formed in a portion where the connecting members 22a, 22b, and 22c merge. The width of the merged portion is larger than the above-described widths t1 and t2, and includes a useless area. Therefore, by forming the hole 26, a useless area is reduced, and the weight of the fuel cell 10 is reduced. In addition, in order to reduce the useless area | region of a junction part, it is not restricted to forming the hole 26, A notch can also be formed.

  Next, in the fuel cell 10 configured as described above, a case where a strong impact is applied to the laminate 14 in the vehicle traveling direction at the time of a vehicle front collision will be described.

  Under the influence of the inertial mass of the laminate 14 due to the impact, the tension shaft 18 on the vehicle traveling direction side and the tension shaft 18 provided in the center of the side surface 14a tend to bend. Connecting members 22a and 22c are connected to each central portion 20 of the tension shaft 18 and each end portion 24 of the tension shaft 18 on the opposite side of the vehicle traveling direction. That is, a portion having the smallest rigidity between the tension shaft 18 on the vehicle traveling direction side and the tension shaft 18 provided at the center of the side surface 14a and a portion having the largest rigidity on the tension shaft 18 on the opposite side in the vehicle traveling direction. They are connected by connecting members 22a and 22c, respectively. With this configuration, the central portion 20 which is the least rigid portion between the tension shaft 18 on the vehicle traveling direction side and the tension shaft 18 provided at the center of the side surface 14a is reinforced and the rigidity is increased. 18 bending is suppressed. Similarly, in the case of a vehicle rear collision, the connecting members 22b and 22c similarly suppress the bending of the tension shaft 18 on the opposite side in the vehicle traveling direction.

  Therefore, in the present embodiment, the displacement of the unit cell 12 can be reliably suppressed by simply adding the simple structure of the connecting member 22c from the configuration of the above-described embodiment, and as a result, the resistance of the stacked body 14 can be reduced. The impact property can be further improved.

  DESCRIPTION OF SYMBOLS 10 Fuel cell, 12 unit cell, 14 laminated body, 14a side surface, 16 end plate, 18 tension shaft, 20 center part, 22 connection member, 24 end part, 26 hole.

Claims (9)

A laminated body constituted by laminating a plurality of unit cells;
A set of end plates provided at both ends of the stack in the stacking direction;
A tension shaft that fits on the side surface of the laminate in the laminating direction and fastens the set of end plates so as to tighten the laminate from both ends.
In a vehicle fuel cell having
A connecting member that connects the central part of the tension shaft in the stacking direction and the corners of the fuel cell on the side surface, the two corners being farthest from the central part;
A fuel cell for a vehicle. The vehicle fuel cell according to claim 1,
The tension shaft has a first tension shaft and a second tension shaft which are provided on the side surface of the laminated body at intervals.
The connecting member is
A first connecting member that connects a central portion of the first tension shaft and two first corner portions corresponding to the central portion;
A second connecting member that connects the central portion of the second tension shaft and the two second corner portions corresponding to the central portion;
Having
A fuel cell for a vehicle. The vehicle fuel cell according to claim 2,
The first tension shaft and the second tension shaft are respectively provided on opposite sides of the side surface.
A fuel cell for a vehicle. The vehicle fuel cell according to claim 3, wherein
The tension shaft further includes a third tension shaft between the first tension shaft and the second tension shaft,
The connecting member includes a third connecting member that connects the center portion of the third tension shaft and the first and second corner portions.
A fuel cell for a vehicle. The vehicle fuel cell according to claim 4, wherein
Each connecting member is strip-shaped,
A fuel cell for a vehicle. The vehicle fuel cell according to claim 5, wherein
The first and second connecting members and the third connecting member are merged and integrated on the way to the first and second corners,
A fuel cell for a vehicle. The fuel cell for a vehicle according to claim 6, wherein
The width of the portion where the first and second connecting members and the third connecting portion are integrated is larger than the width of the first and second connecting members other than the portion,
A fuel cell for a vehicle. The vehicle fuel cell according to claim 7, wherein
The ratio of the width of the integrated part and the widths of the first and second connecting members other than the part is 2: 1.
A fuel cell for a vehicle. The fuel cell for a vehicle according to claim 1,
The corner is the end of the tension shaft in the stacking direction,
A fuel cell for a vehicle.

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