Secondary cell safety device including pressure release mechanism and current cutoff mechanism

摘要

Disclosed is a safety device of a secondary cell, which comprises a lid having an opening section and directly or indirectly fixed for closing a cell case; a pressure receiving means covering the opening section and having flexibility to displace with an internal pressure of the cell; an element having a conductive path connected at one end to an internal electrode of the cell and at the other end to an external electrode, for breaking the conductive path with displacement of the pressure receiving means resulting from a change in the internal pressure of the cell; and locking pawls which fasten the pressure receiving means to the lid by staking to close the cell interior, to thereby keep the cell interior closed when the internal pressure is at a specific value or less and to release a gas from inside through a gap produced between the pressure receiving means and the lid by unfastening staked sections when the internal pressure has exceeded the specific value.