Protection circuit board, secondary battery and battery pack

摘要

A protection circuit board, a secondary battery with the protection circuit board, and a battery pack comprising the secondary battery.
A PTC device which is a secondary protection device is provided on the protection circuit board, and is installed in electrical connection with an electrode terminal of a bare cell of the secondary battery. According to a structural configuration where the PTC device is electrically connected to the bare cell while being installed on the protection circuit board, the PTC device sensitively responds to temperature changes of the bare cell to thereby cut off a flow of electric current. Due to such a structural configuration of the PTC device, formation of an electrode lead is excluded for electrical connection with the bare cell on the protection circuit board. Consequently, a pattern-forming area which is designed on the protection circuit board increases.