JP2011253730A - Fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell laminate which eliminates dead space between a case and the cell laminate and makes it easy to replace cells in the case.SOLUTION: This invention relates to a fuel cell stack including a cell laminate formed by laminating multiple cells which generate electricity from an electrochemical reaction of fuel gas and oxidation gas, a case housing the cell laminate, an end plate arranged on at least one end of the cell laminate in the cell laminating direction, and a tension member fixing the cell laminate in the cell laminating direction. The case includes a body and a cover. At least one side surface of the body which is formed along the cell laminating direction and an end surface of the body, which is located at the one end in the cell laminating direction, are opened. The body includes a partition separating the opening portion of the end surface from the opening portion of the side surface. The cover covers at least the opening of the end surface and the opening of the side surface.

Description

  The present invention relates to a case for accommodating a cell stack constituting a fuel cell stack.

  Conventionally, a cell stack in which cells (fuel cells) that generate electricity using an electrochemical reaction between a fuel gas (hydrogen) and an oxidizing gas (air) are stacked, and a case that houses the cell stack is provided. Fuel cell stacks are known.

  For example, Patent Document 1 discloses a fuel cell stack in which a cell stack is accommodated in a case having one of side surfaces along the cell stacking direction opened, and the cell stack is compressed by a load adjusting screw that applies a load in the stacking direction. Is disclosed.

  Further, for example, Patent Document 2 discloses a fuel cell stack in which a cell stack is accommodated in a case having an open end face on one end side in the cell stacking direction.

  Further, for example, Patent Document 3 discloses a fuel cell stack provided with a tension shaft extending over the entire cell stack in the cell stacking direction in order to apply a fastening load uniformly to the cell stack. Yes.

  Further, for example, in Patent Document 4, a rolling surface that rolls on an inclined surface by an external force applied across the cell stacking direction between the end plate and a fixed plate having an inclined surface tilted with respect to the cell stacking direction. There is disclosed a fuel cell stack in which a moving roller is interposed and a cell stack between fixed plates can be moved to a side where the inclined surface interval is narrow by the rolling roller.

  In addition, for example, in Patent Documents 5 and 6, a cylindrical cover having both ends opened is disposed so as to cover a cell stack between two end plates for the purpose of water discharge and dust resistance. An improved fuel cell stack is disclosed.

JP 2002-134154 A Korean Registered Patent No. 875579 JP 2007-184200 A JP 2009-59535 A JP 2009-170169 A JP 2008-159546 A

  In such a fuel cell stack, it is required that the dead space in the case is eliminated and the replacement of the cell in the case is easy although it occurs when the cell stack is compressed.

  Accordingly, an object of the present invention is to provide a fuel cell stack in which a dead space between the case and the cell stack is eliminated and the cells in the case can be easily replaced.

  The present invention provides a cell stack in which a plurality of cells that generate power by an electrochemical reaction between a fuel gas and an oxidizing gas are stacked, a case that houses the cell stack, and at least one of the cell stacks in the cell stacking direction. A fuel cell stack including an end plate disposed at an end and a tension member that fixes the cell stack in the stacking direction, wherein the case includes a main body and a cover, and the main body includes At least one side surface of the side surface along the cell stacking direction and an end surface on one end side in the cell stacking direction are opened, and includes a partition portion that partitions the open portion of the end surface and the open portion of the side surface, and the cover portion is at least The open part of the end surface and the open part of the side surface are covered.

  In the fuel cell stack, the tension member extends along a cell stacking direction of the cell stack, one end of the tension member is fixed on the end plate side, and the other end of the tension member is It is preferable to be fixed on the end face side of the main body on the other end side in the cell stacking direction.

  Further, in the fuel cell stack, the tension member includes a fixing pin that fixes the end plate so as to be slidable in the cell stacking direction, and a pin fixing groove that is provided in the main body portion and into which the fixing pin is inserted. Are preferably provided.

  In the fuel cell stack, a guide member that supports the cell stack is preferably formed along the cell stacking direction on a side surface of the main body section along the cell stacking direction.

  Moreover, it is preferable that the fuel cell stack further includes a fixture that fixes the end plate via a side surface of the main body portion along the cell stacking direction.

  Further, in the fuel cell stack, a counterbore is formed on a surface of the end plate opposite to the cell stack side, and the end plate is fixed by contacting the case from the counterbore through the end plate. It is preferable to provide a fixture.

  Further, in the fuel cell stack, it is preferable that a corner portion between an end surface of the main body portion on the other end side in the cell stacking direction and a side surface along the cell stacking direction is a groove having a curvature R.

  According to the present invention, the dead space between the case and the cell stack is eliminated, the fuel cell stack can be miniaturized, and the serviceability that the cells in the case can be easily replaced is improved. Can be made.

It is a schematic cross section which shows an example of a structure of the fuel cell stack concerning this embodiment. It is a model perspective view which shows an example of a structure of the case of this embodiment. It is a schematic cross section which shows an example of a structure of the fuel cell stack in the AA line of FIG. It is a schematic cross section which shows another example of a structure of the fuel cell stack which concerns on this embodiment. It is a schematic cross section which shows another example of a structure of the fuel cell stack which concerns on this embodiment. FIG. 6 is a schematic plan view of the end plate of FIG. 5. (A), (B) is a schematic plan view which shows another example of a structure of a tension member. (A), (B) is a schematic plan view which shows another example of a structure of a tension member. It is a model perspective view which shows an example of a structure of a main-body part. (A)-(C) are partial schematic cross sections which show another example of a structure of the main-body part which comprises a case. It is a partial schematic cross section which shows another example of a structure of the main-body part which comprises a case.

  Embodiments of the present invention will be described below.

  FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the fuel cell stack according to the present embodiment. FIG. 2 is a schematic perspective view showing an example of the configuration of the case of the present embodiment. As shown in FIGS. 1 and 2, the fuel cell stack 1 includes a cell stack 12 in which a plurality of cells 10 that generate power by an electrochemical reaction between a fuel gas and an oxidizing gas are stacked, and a case that houses the cell stack 12. 14, a shim 16 and an end plate 18 that are sequentially arranged from the cell stack 12 side, and a tension member 20 that fixes the cell stack 12 in the stacking direction, at one end in the cell stacking direction. In addition, although description in a figure is abbreviate | omitted, the terminal plate as a collector plate, the insulator as an insulating plate, etc. are arrange | positioned at the both ends of the cell laminated body 12. FIG. The shim 16 is a plate material that adjusts the length of the cell stack 12 in the stacking direction, and is not necessarily provided.

  The case 14 that accommodates the cell stack 12 includes a main body portion 22 and cover portions (24, 26). As shown in FIG. 2, the main body portion 22 includes a side opening portion 28 in which at least one side wall of the side wall along the cell stacking direction (X direction) of the cell stack 12 to be accommodated is opened and one of the cell stacking directions. An end surface opening portion 30 having an end wall on the end side and a column (hereinafter referred to as a partition member 32) that partitions the side surface opening portion 28 and the end surface opening portion 30 are provided. The side opening 28 is a space for taking out the cell 10 from the case 14 mainly when the fuel cell stack 1 is repaired or inspected. Therefore, when the fuel cell stack 1 is installed in terms of workability, The upper surface of the case 14 is preferable. In addition, although description in a figure is abbreviate | omitted, piping which supplies fuel gas and oxidizing gas to the cell 10 is connected to the end surface wall of the other end side of the main body part 22 in the cell lamination direction.

  The main body 22 is preferably an integrally molded product that is seamless between the side walls or between the side wall and the end wall in terms of impact resistance, water resistance, dust resistance, and the like. It may be configured to be fixed by, for example.

  The cover portions (24, 26) include a side surface cover portion 24 that covers the side surface opening portion 28 and an end surface cover portion 26 that covers the end surface opening portion 30. As shown in FIG. 1, the side cover portion 24 and the end surface cover portion 26 are fixed to the main body portion 22 by a fixing tool 34 such as a bolt. Further, as shown in FIG. 1, a part of the side surface cover portion 24 and the end surface cover portion 26 is arranged on a partition member 32 that partitions the side surface opening portion 28 and the end surface opening portion 30 of the main body portion 22, such as bolts. It is fixed by a fixing tool 36. Thus, by providing the partition member 32, the cover part (24, 26) can be face-sealed, and waterproofness and dustproofness can be sufficiently secured.

  The material of the main body portion 22 and the cover portions (24, 26) is preferably a metal material such as aluminum casting in terms of cost, strength, and easy manufacture.

  The tension member 20 is a rod-like or plate-like member that extends along the cell stacking direction of the cell stack 12. One end of the tension member 20 is supported by a fixture 38 such as a nut via the end plate 18, and the other end is supported by a fixture 40 such as a plate nut via the end face wall of the main body 22. Specifically, the tension member 20 is inserted into a hole formed in the end face wall of the end plate 18 (and the shim 16) and the main body 22, and a fixture such as a nut (38) is formed from the outside of the end plate 18 and the end face wall. 40), the tension member 20 is fixed. Thereby, a fastening load in the cell stacking direction is applied to the cell stack 12 and the cell stack 12 is fixed to the case 14. The method of fixing the tension member 20 is not limited to the above, and the tension member 20 may be fixed to the case 14 in any way as long as the cell stack 12 can be fixed in the cell stacking direction.

  As described above, the main body portion 22 includes the side surface opening portion 28 in which at least one side wall of the side walls along the cell stacking direction is open and the end surface opening portion 30 in which the end surface wall on one end side in the cell stacking direction is open. By forming, the cell 10 in the case 14 can be easily taken out (mainly from the side surface opening portion 28). Further, since the end face wall on the one end side of the main body portion 22 is opened, there is almost no dead space between the case 14 and the cell 10, and the fuel cell stack 1 can be downsized.

  As shown in FIG. 1, the fuel cell stack 1 of the present embodiment preferably includes a fixture 42 that fixes the end plate 18. As in the present embodiment, in the main body portion 22 in which the end surface opening portion 30 and the side surface opening portion 28 are formed, the end plate 18 cannot be supported by the main body portion 22 and is mounted on a vehicle having a lot of vibration or the like. In some cases, it is preferable to fix the end plate 18. Specifically, an internal thread portion is formed in the end plate 18, an internal thread portion is formed at the position of the side wall of the main body portion 22 that engages with the bolt hole, and the fixing tool 42 such as a bolt is attached to the side surface of the main body portion 22. The end plate 18 is fixed to the main body portion 22 by being screwed into the wall and the internal thread portion of the end plate 18.

  FIG. 3 is a schematic cross-sectional view showing an example of the configuration of the fuel cell stack taken along line AA in FIG. As shown in FIG. 3, a guide member 44 that supports the cell stack 12 is formed in the side wall of the main body 22 along the cell stacking direction. By providing the guide member 44, when assembling the fuel cell stack 1, it becomes easy to guide the cells 10 into the case 14, and the cells 10 can be laminated smoothly. Further, the guide member 44 can suppress the bending of the cell 10 when an impact or the like is applied to the case 14. The guide member 44 of the present embodiment has a rib shape, but the guide member 44 may be a groove that engages with the protrusion as long as the protrusion can be formed in the cell 10.

  FIG. 4 is a schematic cross-sectional view showing another example of the configuration of the fuel cell stack according to the present embodiment. In the fuel cell stack 2 shown in FIG. 4, the same components as those of the fuel cell stack 1 shown in FIG. The fixing tool 46 shown in FIG. 4 is a set screw or the like such as a female screw. For example, a female screw part is formed in the partition member 32, the fixing tool 46 is passed through the female screw part of the partition part, and the tip of the fixing tool 46 is ended. The end plate 18 is fixed in contact with the plate 18. In this way, by adopting a method in which the end plate 18 is fixed by bringing the end plate 18 into contact with the fixing plate 46 such as a set screw, the end plate 18 is adjusted to the length of the cell stack 12 in the stacking direction. Since it can be moved in the stacking direction or fixed, the number and thickness of the shims 16 can be reduced, or the shims 16 can be eliminated.

  In the present embodiment, the end plate 18 is fixed by passing a fixing tool 46 such as a set screw through the female screw portion formed in the partition member 32. However, the present invention is not necessarily limited thereto. 24, 26) and the side wall of the main body 22 and the like, and a fixing tool 46 such as a set screw is passed through the female screw part, and the end of the fixing tool 46 is brought into contact with the end plate 18 to thereby end the end plate 18. May be fixed.

  FIG. 5 is a schematic cross-sectional view showing another example of the configuration of the fuel cell stack according to the present embodiment. FIG. 6 is a schematic plan view of the end plate of FIG. In the fuel cell stack 3 shown in FIG. 5, the same components as those in the fuel cell stack 1 shown in FIG. A counterbore 48 is formed in the end plate 18 of the fuel cell stack 3 shown in FIG. 5 on the surface opposite to the surface on the cell stack 12 side. Further, as shown in FIG. An internal thread 50 that penetrates the counterbore 48 is formed in the part. In this embodiment, the fixing tool 46 such as a set screw is passed from the counterbore 48 side through the female screw portion 50 formed on the side portion of the end plate 18, and the tip of the fixing tool 46 such as the set screw is inserted into the main body portion. 22 and the cover portions (24, 26), and the end plate 18 is fixed. By fixing the end plate 18 in this way, it is not necessary to form the female screw portion 50 through which the fixing tool 46 such as a set screw is passed through the main body portion 22 or the cover portion (24, 26). Dustproofness can be improved. If the strength of the end plate 18 can be ensured, the area, depth, number, etc. of the counterbore 48 are not particularly limited, but in terms of weight reduction of the end plate 18, the area of the counterbore 48 is reduced. Etc. are preferably increased. Since the end plate 18 is fixed by contacting a fixing tool 46 such as a set screw through the end plate 18 to the case 14, the end plate 18 is matched to the length of the cell stack 12 in the stacking direction. Can be moved in the cell stacking direction and can be fixed, so that the number and thickness of the shims 16 can be reduced or the shims 16 can be eliminated.

  FIGS. 7A and 7B and FIGS. 8A and 8B are schematic plan views illustrating another example of the configuration of the tension member. The tension member shown in FIGS. 7A and 7B is an alternative to the tension member 20 shown in FIG. 1, and includes a fixing pin 52 that fixes the end plate 18 to be slidable in the cell stacking direction (X direction); A pin fixing groove 54 into which the fixing pin 52 is inserted. FIG. 9 is a schematic perspective view showing an example of the configuration of the main body. As shown in FIG. 9, the pin fixing groove 54 is formed in the side wall of the main body 22 or the partition member 32.

  7A and 7B, the pin fixing groove 54 is formed so that the fixing pin 52 moves in the cell stacking surface direction (Y direction) of the cell 10. When such a fixing pin 52 and a pin fixing groove 54 are provided, the end portion 18a of the end plate 18 that contacts the fixing pin 52 is processed into an inclined shape. Then, as shown in FIG. 7B, the end plate 18 can be slid in the cell stacking direction (X direction) by moving the fixing pin 52 in the Y direction. That is, even if the length of the cell stack 12 changes in the cell stacking direction due to the increase or decrease in the number of cells, the fixing pin 52 is moved according to the change and the end plate 18 is slid in the cell stacking direction. It becomes possible to apply a fastening load in the cell stacking direction to the cell stack 12 and fix the cell stack 12 to the case 14.

  In the tension member shown in FIGS. 8A and 8B, the pin fixing groove 54 is formed so that the fixing pin 52 is inclined and moved with respect to the stacking surface direction (Y direction) of the cell 10. When such a fixing pin 52 and a pin fixing groove 54 are provided, it is not necessary to process a part of the end plate 18 into an inclined shape. Then, as shown in FIG. 8B, the end plate 18 can be slid in the cell stacking direction by the tilting movement of the fixing pin 52 with respect to the Y direction. That is, even if the length of the cell stack 12 changes in the cell stacking direction due to the increase or decrease in the number of cells, the fixing pin 52 is tilted and the end plate 18 is slid in the cell stacking direction according to the change. Accordingly, it is possible to apply a fastening load in the cell stacking direction to the cell stack 12 and fix the cell stack 12 to the case 14. Further, the number and thickness of the shims 16 can be reduced, or the shims 16 can be eliminated.

  A plurality of fixing pins 52 and pin fixing grooves 54 are preferably provided, but the number is particularly limited as long as the end plate 18 can be slid in the cell stacking direction and the cell stack 12 can be fixed in the cell stacking direction. It is not something.

  FIGS. 10A to 10C are partial schematic cross-sectional views showing another example of the configuration of the main body portion constituting the case. As shown in FIGS. 10A to 10C, the corner portion 56 between the end face wall and the side wall of the main body portion 22 is preferably a groove 58 having a curvature R. The groove 58 may be formed from the corner portion 56 to the side wall as shown in FIG. 10A, or from the corner portion 56 to the end wall as shown in FIG. 10B. Alternatively, as shown in FIG. 10C, it may be formed from the end wall to the side wall.

  FIG. 11 is a partial schematic cross-sectional view showing another example of the configuration of the main body constituting the case. As shown in FIG. 11, since the cell 10 normally contacts the curvature R formed at the corner portion 56 between the end face wall and the side wall of the main body portion 22, a large stress is applied to the corner portion 56. However, as shown in FIG. 9, by making the corner portion 56 a groove 58 having a curvature R, the stress of the corner portion 56 due to the contact of the cell 10 can be relieved.

  Further, as shown in FIG. 10A, in order to secure the strength of the main body portion 22, the side wall (or the side wall) corresponding to the groove 58 is compensated to compensate for the thickness of the main body portion 22 that is reduced by forming the groove 58. It is preferable to project the end wall) outward (form the projecting portion 60).

1 to 3 Fuel cell stack, 10 cells, 12 cell stack, 14 case, 16 shim, 18 end plate, 20 tension member, 22 body part, 24 side cover part, 26 end face cover part, 28 side open part, 30 end face Opening part, 32 partition member, 34, 36, 38, 40, 42, 46 fixture, 44 guide member, 48 counterbore, 50 female thread part, 52 fixing pin, 54 pin fixing groove, 56 corner part, 58 groove, 60 Overhang.

Claims (7)

A cell stack in which a plurality of cells that generate power by an electrochemical reaction between a fuel gas and an oxidizing gas are stacked; a case for housing the cell stack; and a cell stack in at least one end in the cell stacking direction. A fuel cell stack comprising an end plate and a tension member for fixing the cell stack in the stacking direction,
The case includes a main body portion and a cover portion,
The main body includes a partition that opens at least one side surface along the cell stacking direction and an end surface on one end side in the cell stacking direction, and partitions the open portion of the end surface from the open portion of the side surface. ,
The fuel cell stack, wherein the cover part covers at least the open part of the end face and the open part of the side face. The fuel cell stack according to claim 1, wherein the tension member is extended along a cell stacking direction of the cell stack.
One end of the tension member is fixed on the end plate side, and the other end of the tension member is fixed on the end surface side of the main body portion on the other end side in the cell stacking direction.   2. The fuel cell stack according to claim 1, wherein the tension member includes a fixing pin that fixes the end plate so as to be slidable in the cell stacking direction, and a pin that is provided on the main body and into which the fixing pin is inserted. A fuel cell stack comprising a fixing groove.   4. The fuel cell stack according to claim 1, wherein a guide member that supports the cell stack along the cell stacking direction is provided on a side surface of the main body section along the cell stacking direction. 5. A fuel cell stack characterized in that is formed.   4. The fuel cell stack according to claim 1, further comprising: a fixture that fixes the end plate through a side surface of the main body portion along a cell stacking direction. 5. stack.   It is a fuel cell stack of any one of Claims 1-3, Comprising: A counterbore is formed in the surface on the opposite side to the said cell laminated body side of the said end plate, Through the said endplate from the said counterbore A fuel cell stack, comprising: a fixture that contacts the case and fixes the end plate.   The fuel cell stack according to any one of claims 1 to 3, wherein a corner portion between an end surface of the main body portion on the other end side in the cell stacking direction and a side surface along the cell stacking direction has a curvature R. A fuel cell stack, wherein the fuel cell stack has a groove.