Current interruption device and electricity storage device using the current interruption device

Patent metadata

Field	Value
Publication number	US-2016190657-A1
Application number	US-201414908729-A
Country	US
Kind code	A1
Filing date	Apr 3, 2014
Priority date	Jul 30, 2013
Publication date	Jun 30, 2016
Grant date	—

Abstract

A current interruption device includes a deforming plate, a contact plate and a conducting plate which configure a current path. The deforming plate includes one surface on an opposite side from the contact plate facing a first space, a pressure of which is retained to a same pressure as the internal pressure of the casing and the other surface opposed to the contact plate facing a second space, a pressure of which is retained to a same pressure as an external pressure of the casing. When the internal pressure rises above the predetermined level, the second contact portion is separated from the conducting plate by deformation of the deforming plate toward the contacting plate.

First claim

1 - 8 . (canceled)

9 . A current interruption device used for an electricity storage device, the current interruption device configured to electrically connect a positive or negative electrode terminal and an electrode assembly that comprises a positive electrode and a negative electrode, and to interrupt a serial current path of the electrode terminal and the electrode assembly when an internal pressure of a closed casing accommodating the electrode assembly rises above a predetermined level, the current interruption device comprising:
a deforming plate configured to deform when the internal pressure rises above the predetermined level; and a contact plate and a conducting plate which configures the current path in a state where the contact plate and the conducting plate are electrically connected to the electrode assembly and the electrode terminal, wherein the conducting plate is disposed to be intervened between the deforming plate and the contact plate, the conducting plate includes a first contact portion configured to contact the contact plate, the contact plate includes a second contact portion configured to contact the first contact portion, a first space is provided in the casing, a second space is provided between the deforming plate and the contact plate, an outside of the casing and the second space are communicated by a communicating portion, the deforming plate includes one surface of the deforming plate on an opposite side from the contact plate, facing the first space, a pressure of which is retained to a same pressure as the internal pressure of the casing, and the other surface opposed to the contact plate facing the second space, a pressure of which is retained to a same pressure as an external pressure of the casing through the communicating portion, the deforming plate includes a contacting portion configured to contact the first contact portion or the second contact portion, and at least the second contact portion, among the first contact portion and the second contact portion, is configured to be separable from the conducting plate by deformation of the deforming plate causing the contacting portion to move toward the contact plate when the internal pressure rises above the predetermined level.

10 . The current interruption device according to claim 9 further comprising:
a conductive cover electrically connected to the contact plate, wherein
one side portion of the cover is exposed to the outside of the casing through an opening provided on the casing, and the other side portion of the cover configures a part of a case body of the current interruption device,
a communicating hole piercing the cover from one side portion to the other side portion is provided in the cover, and
the second space is retained to the same pressure as the external pressure of the casing through the communicating hole.

11 . The current interruption device according to claim 10 , wherein
the one side of the cover exposed to the outside of the casing includes a connecting portion connecting a conductive member configured to supply electric power to an external device from the electrode assembly.

12 . The current interruption device according to claim 11 , wherein
the connecting portion is provided on an inner surface of the communicating hole of the cover and includes an inner thread for fixing the conductive member.

13 . The current interruption device according to claim 10 , wherein
an outer thread is provided on a side surface on the one side of the cover exposed to the outside of the casing, and the current interruption device is fixed to the casing by holding a wall of the casing between a fixing member engaged with the outer thread and a part of the cover positioned in the casing.

14 . The current interruption device according to claim 9 , wherein
a center portion of the deforming plate provides an insulating projection projecting toward the contact plate, and the projection includes the contacting portion.

15 . The current interruption device according to claim 14 further comprising:
a contacting member disposed between the deforming plate and the conducting plate; and
an insulating cap,
wherein
the insulating projection is composed of the contacting member and the cap,
the contacting member is disposed in a center portion of a surface of the deforming plate facing the conducting plate,
the cap includes a cap portion covering the contacting member, and a guide portion regulating a position of the cap portion in a plane orthogonal to a direction connecting the deforming plate and the conducting plate.

16 . An electricity storage device comprising:
the current interruption device according to claim 9 .

Assignees

• Toyota Jidoshokki Kk
• Eagle Ind Co Ltd

Inventors

• Hirose Takayuki
• Akiyama Hirokuni
• Okuda Motoaki
• MINAGATA Atsushi
• Nishihara Hiroyasu
• Mune Shimpei
• Iwa Toshiaki
• Ogawa Yoshihiro
• MITSUYASU Makoto
• AKIYOSHI Norimitsu

Classifications

• H01M50/176

  for prismatic or rectangular cells (H01M50/181 takes precedence) · CPC title

• H01M50/553

  Terminals adapted for prismatic, pouch or rectangular cells · CPC title

• H01M50/55

  on the same side of the cell · CPC title

• H01M10/4257 Primary

  Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries · CPC title

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title