SECONDARY BATTERY

A conductive member is disposed near a side of the sealing plate facing an electrode assembly with a first insulating member disposed therebetween. The conductive member has a conductive-member opening portion. The conductive member is connected to a positive electrode terminal that projects toward au outside of the battery from the sealing plate. The conductive-member opening portion of the conductive member is sealed by a deformation plate. The deformation plate is connected to a first positive-electrode current collector of a current collecting member, which is electrically connected to positive electrode plates. The deformation plate is deformed in response to an increase in pressure in a rectangular exterior body, and the conductive path between the positive electrode plate and the positive electrode terminal is broken in response to the deformation of the deformation plate. A cover is disposed between the first positive-electrode current collector and the electrode assembly.