Electrical energy storage device

Patent metadata

Field	Value
Publication number	US-10340501-B2
Application number	US-201515305545-A
Country	US
Kind code	B2
Filing date	Feb 27, 2015
Priority date	Apr 23, 2014
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

A current interruption device includes a first conductive member, a second conductive member, a first deformable member, a second deformable member, and a first seal member. The second conductive member is disposed at a position opposed to the first conductive member. A center portion of the first deformable member is fixed to the second conductive member. The second deformable member is disposed on a side opposite to the first deformable member relative to the second conductive member. The first seal member is disposed between the first conductive member and the second conductive member. A second seal member is disposed between the first conductive member and the casing. A gas permeability between the casing and the first conductive member is equal to or less than a gas permeability between the first conductive member and the second conductive member.

First claim

The invention claimed is:

1. An electrical energy storage device comprising a current interruption device configured to interrupt conduction between an electrode and an electrode terminal when pressure in a casing exceeds a predetermined value, wherein
the electrode is accommodated in the casing, and
the electrode terminal is fixed to the casing and configured to transfer electricity with the electrode,
wherein
the current interruption device comprises:
a first conductive member fixed to the casing and connected to the electrode terminal;
a second conductive member disposed at a position spaced from and opposed to the first conductive member, and connected to the electrode;
a first deformable member disposed between the first conductive member and the second conductive member, an end of the first deformable member being connected to the first conductive member, a center portion of the first deformable member being connected to the second conductive member, and the first deformable member being configured to be brought out of conduction with the second conductive member when the pressure in the casing exceeds the predetermined value;
a second deformable member disposed on a side opposite to the first deformable member relative to the second conductive member, and being provided with a projection, on a second conductive member side, that has a shape projecting toward the second conductive member; and
a first seal member disposed between the first conductive member and the second conductive member and keeping an inside of the current interruption device airtight against an outside of the current interruption device,
wherein
a second seal member disposed between the casing and the first conductive member and keeping an inside of the casing airtight against an outside of the casing, and
a second gas permeability between the casing and the first conductive member which is where the second seal member seals is less than a first gas permeability between the first conductive member and the second conductive member which is where the first seal member seals.

2. The electrical energy storage device according to claim 1 , wherein
a material of the first seal member is rubber, and a material of the second seal member is resin.

3. The electrical energy storage device according to claim 2 , wherein
a circumferential length of the first seal member is longer than a circumferential length of the second seal member.

4. The electrical energy storage device according to claim 3 ,
wherein the electrical energy storage device is a secondary battery.

5. The electrical energy storage device according to claim 1 , wherein
a circumferential length of the first seal member is longer than a circumferential length of the second seal member.

6. The electrical energy storage device according to claim 1 ,
wherein the electrical energy storage device is a secondary battery.

7. The electrical energy storage device according to claim 1 , wherein the end of the first deformable member is welded to the first conductive member and the first seal member does not contact the first deformable member.

8. The electrical energy storage device according to claim 1 , further comprising an insulating member disposed between the first conductive member and the second conductive member so as to maintain a clearance between the first conductive member and the second conductive member.

Assignees

• Toyota Jidoshokki Kk
• Eagle Ind Co Ltd

Inventors

• MINAGATA Atsushi
• Okuda Motoaki
• Iwa Toshiaki
• Ogawa Yoshihiro
• MITSUYASU Makoto
• AKIYOSHI Norimitsu

Classifications

• H01M50/583

  in response to current, e.g. fuses · CPC title

• H01M50/186

  characterised by the disposition of the sealing members · CPC title

• H01M50/193

  Organic material · CPC title

• H01G9/10

  Sealing, e.g. of lead-in wires · CPC title

• H01G9/12 Primary

  Vents or other means allowing expansion · CPC title