Power storage apparatus

Patent metadata

Field	Value
Publication number	US-10916751-B2
Application number	US-201816488346-A
Country	US
Kind code	B2
Filing date	Feb 27, 2018
Priority date	Feb 28, 2017
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A power storage apparatus is configured such that a region surrounded by a plane connecting the outline of a pressure release valve and the outline of a tab-side end face in an electrode assembly in the shortest distance is defined as a three-dimensional region. The power storage apparatus is provided with a covering portion that covers the entire cross section of the three-dimensional region along the tab-side end face in a space between the tab-side end face and the inner surface of a lid body.

First claim

The invention claimed is:

1. A power storage apparatus comprising:
an electrode assembly in which a positive electrode and a negative electrode are insulated from each other and have a lamination structure;
a positive electrode conductive member connected to a tab of the positive electrode;
a negative electrode conductive member connected to a tab of the negative electrode;
liquid electrolyte;
a case containing the electrode assembly and the liquid electrolyte; and
a pressure release valve that is located in a wall portion of the case and configured to tear when a pressure in the case reaches a release pressure to release the pressure out of the case, wherein
the positive electrode conductive member and the negative electrode conductive member are arranged in a longitudinal direction of the wall portion,
the case has a parallelepiped shape and includes a base wall, which is opposite to the wall portion, two short side walls, which project from short edges of the base wall, and two long side walls, which project from long edges of the base wall,
the electrode assembly has a lamination direction in which the positive electrode and the negative electrode are stacked, the lamination direction is identical with a transverse direction of the wall portion,
the positive electrode conductive member and the negative electrode conductive member have dimensions in the transverse direction of the wall portion that are less than a distance between opposing surfaces of the two long side walls,
a region surrounded by planes connecting an outline of an end face of the electrode assembly that faces an inner surface of the wall portion of the case to an outline of the pressure release valve in shortest distances is defined as a three-dimensional region,
the power storage apparatus further comprises a covering portion that is located in a space between the end face of the electrode assembly and the inner surface of the wall portion, the covering portion covering a cross section of the three-dimensional region that extends along the end face of the electrode assembly over an entire length in the longitudinal direction of the cross section,
the positive electrode conductive member, the negative electrode conductive member, and a shield, which is placed between the positive and negative electrode conductive members, form the covering portion,
the shield includes
a shielding portion placed along the end face of the electrode assembly, and
a spacing portion configured to be in contact with a section of the inner surface of the wall portion around the pressure release valve such that the shielding portion is spaced apart from the wall portion,
the spacing portion includes a plurality of spacing rods projecting from the shielding portion.

2. The power storage apparatus according to claim 1 , wherein the shield includes baffle plates each of which overlaps with a corresponding one of the tabs of different polarities as viewed from a side corresponding to an outer surface of the wall portion and covers the tab along the longitudinal direction of the wall portion.

3. The power storage apparatus according to claim 1 , wherein a center position of the pressure release valve in the longitudinal direction of the wall portion is closer to the negative electrode conductive member than a center position between the tab of the positive electrode and the tab of the negative electrode in the longitudinal direction of the wall portion.

4. The power storage apparatus according to claim 1 , wherein the shield is made of metal.

5. The power storage apparatus according to claim 1 , wherein the shield has heat resistance.

6. The power storage apparatus according to claim 1 , wherein the shield has a flat inner surface.

7. The power storage apparatus according to claim 1 , wherein the shield extends from the wall portion.

8. A power storage apparatus comprising:
an electrode assembly in which a positive electrode and a negative electrode are insulated from each other and have a lamination structure;
a positive electrode conductive member connected to a tab of the positive electrode;
a negative electrode conductive member connected to a tab of the negative electrode;
liquid electrolyte;
a case containing the electrode assembly and the liquid electrolyte; and
a pressure release valve that is located in a wall portion of the case and configured to tear when a pressure in the case reaches a release pressure to release the pressure out of the case, wherein
the positive electrode conductive member and the negative electrode conductive member are arranged in a longitudinal direction of the wall portion,
the case has a parallelepiped shape and includes a base wall, which is opposite to the wall portion, two short side walls, which project from short edges of the base wall, and two long side walls, which project from long edges of the base wall,
the electrode assembly has a lamination direction in which the positive electrode and the negative electrode are stacked, the lamination direction is identical with a transverse direction of the wall portion,
the positive electrode conductive member and the negative electrode conductive member have dimensions in the transverse direction of the wall portion that are less than a distance between opposing surfaces of the two long side walls,
a region surrounded by planes connecting an outline of an end face of the electrode assembly that faces an inner surface of the wall portion of the case to an outline of the pressure release valve in shortest distances is defined as a three-dimensional region,
the power storage apparatus further comprises a covering portion that is located in a space between the end face of the electrode assembly and the inner surface of the wall portion, the covering portion covering a cross section of the three-dimensional region that extends along the end face of the electrode assembly over an entire length in the longitudinal direction of the cross section,
the positive electrode conductive member, the negative electrode conductive member, and a shield, which is placed between the positive and negative electrode conductive members, form the covering portion,
the shield is placed on the end face of the electrode assembly.

9. The power storage apparatus according to claim 8 , wherein the shield includes
a shielding portion placed along the end face of the electrode assembly, and

a spacing portion configured to be in contact with a section of the inner surface of the wall portion around the pressure release valve such that the shielding portion is spaced apart from the wall portion.

10. The power storage apparatus according to claim 9 , wherein the spacing portion is a first rib that projects from the shielding portion toward the wall portion and has a surface intersecting with a gas path extending along a surface direction of the shielding portion.

11. The power storage apparatus according to claim 10 , wherein the first rib is one of ribs projecting from a pair of edges of the shielding portion extending in the longitudinal direction of the wall portion.

12. The power storage apparatus according to claim 10 , wherein the shield further includes a second rib projecting toward the wall portion from an edge of the shielding portion extending in the transverse direction of the wall portion.

13. The power storage apparatus according to claim 12 , wherein the second rib includes a gas passage hole.

14. The power storage apparatus according to claim 12 , wherein
the second rib of the shield is located between the pressure release valve and the positive electrode conductive member,
a path of

Assignees

• Toyota Jidoshokki Kk

Inventors

• Yamashita Yusuke
• Hirose Takayuki
• Suzuki Shinji

Classifications

• H01M50/531 Primary

  Electrode connections inside a battery casing · CPC title

• H01M50/10

  Primary casings; Jackets or wrappings · CPC title

• H01M50/586

  inside the batteries, e.g. incorrect connections of electrodes · CPC title

• H01M50/147

  Lids or covers · CPC title

• H01M50/14

  for protecting against damage caused by external factors · CPC title