Battery pack

Patent metadata

Field	Value
Publication number	US-2018287110-A1
Application number	US-201515764361-A
Country	US
Kind code	A1
Filing date	Oct 22, 2015
Priority date	Oct 22, 2015
Publication date	Oct 4, 2018
Grant date	—

Abstract

A battery pack includes a cell group, a spacer, a plurality of bus bars, and a bus bar holder. The cell group includes stacked unit cells, each including a cell body having a power generation element and an electrode tab having distal end portions bent along the stacking direction. The spacer is disposed between adjacent electrode tabs. The bus bars electrically connect the electrode tabs to each other. The bus bar holder that holds the bus bars. The bus bar holder includes a restricting member disposed between adjacent electrode tabs, and extends along the stacking direction to restrict the electrode tabs by sandwiching the electrode tabs with the spacer. Portions of the electrode tabs are welded to a surface of the bus bars facing the unit cells when the stacking direction positions of the portions of the electrode tabs are restricted by the restricting member and the spacer.

First claim

1 . A battery pack comprising:
a cell group including a plurality of unit cells stacked in a thickness direction, each of the unit cells including a cell body having a power generation element and a flat shape, and an electrode tab protruding out from the cell body, and each of the electrode tabs having distal end portions bent along the stacking direction of the unit cells; a spacer disposed between the electrode tabs that are adjacent to each other in a stacking direction to maintain an interval between the electrode tabs in the stacking direction; a plurality of flat plate shaped bus bars electrically connecting the electrode tabs of at least two of the unit cells to each other; and a bus bar holder that holds the bus bars, the bus bar holder comprising a restricting member disposed between portions of the electrode tabs that are adjacent to each other in the stacking direction of the unit cells, and the restricting member extending along the stacking direction and restricting a stacking direction positions of the portions of the electrode tabs that extend along the stacking direction by sandwiching the electrode tabs with the spacer, the portions of the electrode tabs that extend along the stacking direction being welded to a surface of the bus bars facing the unit cells in a state in which the stacking direction positions of the portions of the electrode tabs are restricted by the restricting member and the spacer.

2 . The battery pack according to claim 1 , wherein
each of the distal end portions of the electrode tabs of at least two of the unit cells and the surface of the bus bars that face the unit cells are brought into contact and welded to each other.

3 . The battery pack according to claim 1 , wherein
a bus bar holder is provided that holds the bus bars in a state before being attached to the cell group.

4 . The battery pack according to claim 1 , wherein
the restricting member is disposed on both end portions of the electrode tabs in a widthwise direction.

5 . The battery pack according to claim 1 , wherein
the restricting member includes a guide portion that extends from a portion of the restricting member opposes the electrode tabs to a proximal end portion of the electrode tabs and slopes such that a distance from the portion of the restricting portion opposing the electrode tabs becomes greater toward the proximal end portion.

6 . (canceled)

7 . The battery pack according to claim 1 , wherein
the spacer comprises a restricting portion disposed between adjacent electrode tabs of the electrode tabs to restrict movement of the adjacent electrode tabs between the restricting member and the spacer, and the spacer further comprises a leg portion extending from the restricting portion toward a different electrode tab of the electrode tabs that is adjacent to the adjacent electrode tabs to restrict the movement of the different electrode tab.

8 . The battery pack according to claim 7 , wherein
a gap is formed between the leg portion of the spacer and the electrode tab that is restricted by the leg portion.

9 . The battery pack according to claim 7 , wherein
the restricting portion includes a surface opposing the electrode tabs, the surface is spaced by a distance from a distal end portion of the leg portion that is greater than a sum of a stacking direction length of the distal end portions of the electrode tabs and a stacking direction length of the restricting member disposed between the electrode tabs and the different one of the electrode tabs.

10 . The battery pack according to claim 5 , wherein
the spacer comprises a restricting portion disposed between adjacent ones of the electrode tabs to restrict movement of the adjacent ones of the electrode tabs between the restricting member and the spacer, and the spacer further comprises a leg portion extending from the restricting portion toward a different electrode tab of the electrode tabs that is adjacent to the adjacent ones of the electrode tabs to restrict the movement of the different electrode tab, and a part of the guide portion most separated from the electrode tabs is farther away from the electrode tabs in the stacking direction than a distal end portion of the leg portion of the spacer.

Assignees

• Nissan Motor

Inventors

• Yanagihara Yasuhiro
• Nakai Masayuki
• Itabashi Manato
• Suzuki Yui
• Nakamoto Masahiro

Classifications

• H01M50/178 Primary

  for pouch or flexible bag cells · CPC title

• H01M10/0472

  Vertically superposed cells with vertically disposed plates · CPC title

• H01M50/566

  by welding, soldering or brazing · CPC title

• H01M50/291

  characterised by their shape · CPC title

• H01M50/507

  comprising an arrangement of two or more busbars within a container structure, e.g. busbar modules · CPC title