Cylindrical lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-9979057-B2
Application number	US-201514958956-A
Country	US
Kind code	B2
Filing date	Dec 4, 2015
Priority date	Jan 8, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A cylindrical lithium ion secondary battery, including a cylindrical can; an electrode assembly in the cylindrical can with an electrolyte solution; and a cap assembly sealing the cylindrical can, the cap assembly including a positive temperature coefficient (PTC) device connected to the electrode assembly, a cap-up connected to the PTC device, solder between the PTC device and the cap-up, and an exterior space without the solder on external circumferences of the PTC device and the cap-up.

First claim

What is claimed is:

1. A cylindrical lithium ion secondary battery, comprising:
a cylindrical can;
an electrode assembly in the cylindrical can with an electrolyte solution; and
a cap assembly sealing the cylindrical can,
the cap assembly including a positive temperature coefficient (PTC) device connected to the electrode assembly, a cap-up connected to the PTC device, solder between the PTC device and the cap-up, and an exterior space without the solder on external circumferences of the PTC device and the cap-up, wherein the cap-up includes an exterior stepped portion protruding toward the exterior space and contacting the PTC device.

2. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein the exterior space has a width in a range of 0.1 mm to 1.5 mm.

3. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein a width of the exterior stepped portion is equal to that of the exterior space.

4. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein the exterior stepped portion includes a plurality of stepped portions spaced apart from each other.

5. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein the exterior stepped portion includes a plurality of serrations.

6. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein a top surface of the cap-up corresponding to the PTC device is planar.

7. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein a top surface of the cap-up corresponding to the PTC device is bent.

8. The cylindrical lithium ion secondary battery as claimed in claim 1 , wherein the cap assembly further includes an interior space without solder on internal circumferences of the PTC device and the cap-up.

9. The cylindrical lithium ion secondary battery as claimed in claim 8 , wherein the cap-up includes an interior stepped portion protruding toward the interior space and contacting the PTC device.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Moon Jinyoung
• Chun Byoungmin
• Kim Shinjung
• Kim Yongtae

Classifications

• H01M10/0587

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M10/4257

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

• H01M10/637 Primary

  characterised by the use of reversible temperature-sensitive devices, e.g. NTC, PTC or bimetal devices; characterised by control of the internal current flowing through the cells, e.g. by switching (means for preventing undesired use or discharge H01M50/572) · CPC title

• H01M10/052 Primary

  Li-accumulators · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title