Fuel cell and manufacturing method of fuel cell

Patent metadata

Field	Value
Publication number	US-2017365872-A1
Application number	US-201715622494-A
Country	US
Kind code	A1
Filing date	Jun 14, 2017
Priority date	Jun 21, 2016
Publication date	Dec 21, 2017
Grant date	—

Abstract

There is provided a fuel cell comprising a cell stacked body and a case configured to surround at least stacked body side faces of the cell stacked body. The case comprises a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle; and a second case configured to include a second case side wall and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle. A first edge of each of the first opposed side walls is joined with a second edge of each of the second opposed side walls. This configuration suppresses size expansion of the fuel cell.

First claim

1 . A fuel cell, comprising:
a cell stacked body provided by stacking a plurality of unit cells, the cell stacked body configured to include stacked body side faces arranged along a stacking direction of the plurality of unit cells; and a case configured to surround at least the stacked body side faces of the cell stacked body, wherein the case comprises:
a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle, the pair of first opposed side walls configured to be opposed to each other across the cell stacked body; and
a second case configured to include a second case side wall that is opposed to the first case side wall across the cell stacked body, and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle, the pair of second opposed side walls configured to be opposed to each other across the cell stacked body, wherein
a first edge of each of the first opposed side walls on an opposite side that is opposite to the first case side wall is joined with a second edge of each of the second opposed side walls on an opposite side that is opposite to the second case side wall.

2 . The fuel cell according to claim 1 ,
wherein a total length of the first opposed side wall and the second opposed side wall that are joined with each other in a first direction in which the first case side wall and the second case side wall are opposed to each other, is shorter than a length of the case in a second direction in which the pair of first opposed side walls are opposed to each other.

3 . The fuel cell according to claim 1 ,
wherein each of the pair of first opposed side walls has a length in a first direction in which the first case side wall and the second case side wall are opposed to each other, that is not less than ⅓ and not greater than ⅔ of a total length of the first opposed side wall and the second opposed side wall that are joined with each other in the first direction, and each of the pair of second opposed side walls has a length in the first direction that is not less than ½ and not greater than ⅔ of the total length of the first opposed side wall and the second opposed side wall that are joined with each other in the first direction.

4 . The fuel cell according to claim 1 , further comprising:
a pair of side wall intervening layers that are placed between a wall constituting part of the case formed by the first opposed side wall and the second opposed side wall that are joined with each other, and the stacked body side faces, the pair of side wall intervening layers arranged to be in contact with the wall and with the stacked body side faces, wherein the pair of side wall intervening layers are compressed by the wall and the stacked body side faces and are arranged across joint portions of the first edges and the second edges in a first direction in which the first case side wall and the second case side wall are opposed to each other.

5 . The fuel cell according to claim 1 , further comprising:
a pair of side wall intervening layers that are placed between a wall constituting part of the case formed by the first opposed side wall and the second opposed side wall that are joined with each other, and the stacked body side faces, the pair of side wall intervening layers arranged to be in contact with the wall and with the stacked body side faces, wherein one of the pair of side wall intervening layers is placed on one side where the first case side wall is located relative to a center of the case in a first direction in which the first case side wall and the second case side wall are opposed to each other, and the other of the pair of side wall intervening layers is placed on the other side where the second case side wall is located relative to the center of the case in the first direction.

6 . The fuel cell according to claim 5 ,
wherein one of the pair of side wall intervening layers is placed on a side nearer to the first case side wall relative to the center of the case in the first direction, and the other of the pair of side wall intervening layers is placed on a side nearer to the second case side wall relative to the center of the case in the first direction.

7 . The fuel cell according to claim 1 ,
wherein the case further comprises a case bottom wall that is located on one side of the cell stacked body in the stacking direction, the first case further comprises a first intersecting wall that is arranged to rise from the circumference of the first case side wall such as to have a draft angle and is configured to intersect with the pair of first opposed side walls, and the second case further comprises a second intersecting wall that is arranged to rise from the circumference of the second case side wall such as to have a draft angle and is configured to intersect with the pair of second opposed side walls, wherein a third edge of the first intersecting wall on an opposite side that is opposite to the first case side wall is joined with a fourth edge of the second intersecting wall on an opposite side that is opposite to the second case side wall, and the first intersecting wall and the second intersecting wall constitute the case bottom wall.

8 . A manufacturing method of the fuel cell according to claim 1 ,
the manufacturing method comprising: (a) a process of placing the first edge and the second edge to abut with each other in an abutment portion and joining the abutment portion by friction stir welding; and (b) a process of placing at least the cell stacked body inside of the case, after the process (a).

9 . A manufacturing method of the fuel cell according to claim 7 ,
the manufacturing method comprising: (a) a process of placing the first edge and the second edge to abut with each other in a first abutment portion and joining the first abutment portion by friction stir welding; (b) a process of placing the third edge and the fourth edge to abut with each other in a second abutment portion and joining the second abutment portion by friction stir welding; and (c) a process of placing at least the cell stacked body inside of the case, after the process (a) and the process (b).

10 . The manufacturing method of the fuel cell according to claim 9 ,
wherein the process (a) performs the friction stir welding by using a first tool configured to include a first shoulder portion in a columnar shape and a first pin protruded from an end surface of the first shoulder portion, and the process (b) performs the friction stir welding by using a second tool configured to include a second shoulder portion in a columnar shape that has a different diameter from a diameter of the first shoulder portion, and a second pin protruded from an end surface of the second shoulder portion.

Assignees

• Toyota Motor Co Ltd

Inventors

• Takabatake Yuma
• Nishiumi Hiroaki
• Itoga Michitaro
• Nishikawa Masahiko

Classifications

• H01M8/2475 Primary

  Enclosures, casings or containers of fuel cell stacks · CPC title

• H01M8/242

  comprising framed electrodes or intermediary frame-like gaskets (H01M8/2425, H01M8/244 take precedence) · CPC title

• H01M8/0232

  Metals or alloys · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/2404 Primary

  Processes or apparatus for grouping fuel cells · CPC title