Lithium ion secondary battery having shape memory safety vent

Abstract

A lithium ion secondary battery has a shape memory safety vent adapted to discharge internal compressed gas by temporarily being opened when the temperature reaches a predetermined level to avoid a swelling phenomenon of the battery and improve safety. The lithium ion secondary battery includes an electrode assembly having first and second electrode plates wound a number of times with a separator interposed between them; a can having an opening formed on a side thereof to contain the electrode assembly; and a cap plate adapted to cover the can and provided with a vent hole on a side thereof, to which a safety vent adapted to deform at a predetermined temperature and discharge gas from inside the can to the exterior is coupled.

Description

[0001] Cross References to Related Applications

[0002] This application claims priority and benefits from Korean Patent Application No. 10-2004-0071415 filed with the Korean Intellectual Property Office on September 7, 2004, the entire contents of which are hereby incorporated by reference. technical field

[0003] The present invention relates to lithium ion secondary batteries, and more particularly, to lithium ion secondary batteries having a shape memory safety vent adapted to release compressed gas inside. Background technique

[0004] A typical lithium-ion secondary battery includes: an electrode assembly consisting of a positive plate to which a positive active material is attached, a negative plate to which a negative active material is attached, and a battery between the positive and negative plates to avoid short circuits and allow only lithium ions to move. a separator wound into a known "jelly roll" structure; an electrolyte for moving lithium ions; a tank for ...

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