BATTERY PACK AND SQUARE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a battery pack that can prevent short-circuiting between a lid member of a square secondary battery and a power generation element.SOLUTION: A battery pack 200 has plural square secondary batteries 100 which are alternately laminated with battery holders 210, and a restraining member for restraining the battery holders 210 and the square secondary batteries 100. The square secondary battery 100 has a power generation element 70 configured by rolling a positive electrode and a negative electrode which are arranged to confront each other through a separator, a battery can 11 in which the power generation element 70 is mounted, and a lid member 12 for sealing the upper opening of the battery can 11. The lid member 12 has end portions 12a confronting the battery holder 210, and an intermediate portion 12b between the end portions 12a. The center Cb in the thickness direction of the intermediate portion 12b is located above the center Ca in the thickness direction of the end portions 12a.SELECTED DRAWING: Figure 9