Rechargeable battery

摘要

A rechargeable battery (100) is providing having an overcharge protection circuit adapted for short-circuiting electrode terminals (41, 42) when a pressure in the internal space of the case (20) extends a predetermined value. The overcharge protection circuit includes an extendable member (50, 53, 54) fixed on an outer surface of the cap plate (30) and being in communication with the internal space of the case (20). The extendable member (50) is expandable such that the extendable member (50, 53, 54) extends at the predetermined pressure to an expanded state thereby closing the overcharge protection circuit so as to allow short-circuiting the electrode terminals (41, 42).