Safety device for secondary battery and battery pack using safety device

摘要

Disclosed herein are a safety device for secondary batteries that is capable of pressing a piezoelectric element using a seesaw member, which is constructed in a variable fixing structure, to generate electric current when a battery cell swells due to the abnormal operation or the degradation of the battery, and controlling the operation of the battery according to the generated electric current using a protection circuit module, thereby securing the safety of the battery, and a battery pack including a battery cell, which has low mechanical strength and high deformability, mounted in a frame member having the safety device, whereby the safety of the battery is improved and the assembly efficiency of the battery pack is improved.