| 摘要 |
PROBLEM TO BE SOLVED: To provide a secondary battery whose current cutoff mechanism operates stably with designated pressure without impairing battery performance and which therefore exhibits high safety and reliability.SOLUTION: A secondary battery 10 includes in a current cutoff mechanism 30 a deformation member 40 which deforms when the internal pressure of a battery 10 increases to designated pressure and a connection member 50 which is connected in part to the deformation member 40 and which cuts off a current conduction path as the deformation member 40 is deformed. The connection member 50 is formed with Al or Al alloy 52, and the deformation member 40 is formed with a main material 42 consisting of Al and a composite material containing a member 44 consisting of Al-Mn based alloy. The deformation member 40 and the connection member 50 are joined together by welding at a position containing the member 44 consisting of Al-Mn based alloy. |
