Top cover assembly of secondary battery and secondary battery

Patent metadata

Field	Value
Publication number	US-10770696-B2
Application number	US-201815950617-A
Country	US
Kind code	B2
Filing date	Apr 11, 2018
Priority date	Jul 20, 2017
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

Provided are a top cover assembly and a secondary battery containing the same. The top cover assembly includes a first electrode terminal, a conduction member, a second electrode terminal, and a top cover plate insulated from the first electrode terminal and electrically connected to the second electrode terminal, the secondary battery further comprises a contact plate which is attached to the top cover plate, the conduction member is insulated from the top cover plate and comprises an electrode terminal connection portion, a first fuse member, a contact plate connection portion, and a connection layer, the first fuse member has a melting point lower than the electrode terminal connection portion and the contact plate connection portion; the first fuse member is connected to the electrode terminal connection portion via the connection layer, and/or the first fuse member is connected to the contact plate connection portion via the connection layer.

First claim

What is claimed is:

1. A top cover assembly of a secondary battery, comprising:
a first electrode terminal, a conduction member, a second electrode terminal, and a top cover plate,
wherein the top cover plate is insulated from the first electrode terminal, and the top cover plate is electrically connected to the second electrode terminal,
wherein the secondary battery further comprises a contact plate, and the contact plate is attached to the top cover plate, and the conduction member is insulated from the top cover plate,
wherein the conduction member comprises an electrode terminal connection portion, a first fuse member, and a contact plate connection portion, wherein the electrode terminal connection portion is electrically connected to the first electrode terminal, the first fuse member is electrically connected between the electrode terminal connection portion and the contact plate connection portion, and a melting point of the first fuse member is lower than a melting point of the electrode terminal connection portion and a melting point of the contact plate connection portion,
wherein the contact plate is configured to deform under an internal pressure of the secondary battery and to be electrically connected to the contact plate connection portion when the internal pressure of the secondary battery exceeds a reference pressure, for forming an electric connection path passing through the first electrode terminal and the second electrode terminal, and
wherein the conduction member further comprises a connection layer, wherein the first fuse member is electrically connected to the electrode terminal connection portion via the connection layer, and the connection layer is configured to enhance a connection strength between the first fuse and the electrode terminal connection portion; and/or the first fuse member is electrically connected to the contact plate connection portion via the connection layer, and the connection layer is configured to enhance a connection strength between the first fuse and the contact plate connection portion.

2. The top cover assembly according to claim 1 , wherein the electrode terminal connection portion and/or the contact plate connection portion is made of a first metal material, the first fuse member is made of a second metal material, and the connection layer is made of a third metal material,
wherein a bonding force formed between the third metal material and the first metal material and a bonding force formed between the third metal material and the second metal material are both greater than a bonding force formed between the first metal material and the second metal material.

3. The top cover assembly according to claim 2 , wherein the third metal material is nickel, nickel alloy, tin, tin alloy, bismuth, or bismuth alloy, the first metal material is aluminum or aluminum alloy, the second metal material is a metal comprising one or more elements selected from a group consisting of bismuth, tin, lead, zinc, and indium.

4. The top cover assembly according to claim 1 , wherein a number of the connection layer is two, wherein one of the two connection layers is connected to the electrode terminal connection portion, the other one of the two connection layers is connected to the first fuse member, and the two connection layers are welded to each other.

5. The top cover assembly according to claim 1 , further comprising an insulation member, wherein the conduction member is insulated from the top cover plate by the insulation member, and
wherein a first through hole is defined in the insulation member, and the contact plate deformed contacts the contact plate connection portion through the first through hole.

6. The top cover assembly according to claim 5 , wherein the insulation member comprises a first portion and a second portion connected to the first portion, wherein the first portion is fixed between the electrode terminal connection portion and the top cover plate, and the second portion surrounds the contact plate connection portion,
wherein the first through hole is defined in the second portion.

7. The top cover assembly according to claim 1 , further comprising a thermo-expandable portion made of an insulative and thermally expandable material,
wherein the first fuse member and the thermo-expandable portion are arranged along a thickness direction of the conduction member, the thermo-expandable portion is located above the first fusing portion, and the thermo-expandable portion is respectively laminated to the electrode terminal connection portion and the contact plate connection portion.

8. The top cover assembly according to claim 7 , further comprising an insulation member, wherein the conduction member is insulated from the top cover plate via the insulation member, and the insulation member and the thermo-expandable portion are formed as an integral structure.

9. A secondary battery comprising the top cover assembly according to claim 1 , a housing and an electrode assembly, wherein the top cover assembly is connected to an opening of the housing and forms a packaging space,
wherein the electrode assembly comprises a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode, wherein the first electrode terminal is electrically connected to the first electrode, and the second electrode terminal is electrically connected to the second electrode; and
wherein the electrode assembly is packaged in the packaging space.

10. The secondary battery according to claim 9 , wherein the secondary battery further comprises a second fuse member, and the first electrode terminal is electrically connected to the first electrode via the second fuse member, and/or
the secondary battery further comprises a third fuse member, and the second electrode terminal is electrically connected to the second electrode via the third fuse member.

11. The secondary battery according to claim 9 , wherein the electrode terminal connection portion and/or the contact plate connection portion is made of a first metal material, the first fuse member is made of a second metal material, and the connection layer is made of a third metal material,
wherein a bonding force formed between the third metal material and the first metal material and a bonding force formed between the third metal material and the second metal material are both greater than a bonding force formed between the first metal material and the second metal material.

12. The secondary battery according to claim 11 , wherein the third metal material is nickel, nickel alloy, tin, tin alloy, bismuth, or bismuth alloy, the first metal material is aluminum or aluminum alloy, the second metal material is a metal comprising one or more elements selected from a group consisting of bismuth, tin, lead, zinc, and indium.

13. The secondary battery according to claim 9 , wherein a number of the connection layer is two, wherein one of the two connection layers is connected to the electrode terminal connection portion, the other one of the two connection layers is connected to the first fuse member, and the two connection layers are welded to each other.

14. The secondary battery according to claim 9 , wherein the top cover assembly further comprises an insulation member, wherein the conduction member is insulated from the top cover plate by the insulation member, and
wherein a first through hole is defined in the insulation member, and the contact plate deformed contacts the contact plate connection portion through the first through hole.

15. The secondary battery according to claim 14 , w

Assignees

• Contemporary Amperex Technology Co Ltd

Inventors

• Chen Baisong
• Wang Peng
• Wu Kai
• Wang Zhiyu
• Chen Xiaobo
• Zhu Taosheng

Classifications

• H01M50/581 Primary

  in response to temperature · CPC title

• H01M50/593

  Spacers; Insulating plates · CPC title

• H01M50/50

  Current conducting connections for cells or batteries · CPC title

• H01M50/147

  Lids or covers · CPC title

• H01M50/553

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