An electrode body, which includes a positive electrode plate and a negative electrode plate, includes a positive-electrode tab group that is composed of a plurality of positive electrode tabs. The positive-electrode tab group is disposed between a sealing plate and an electrode body, and a positive-electrode current collector includes a base portion and a tab connection portion that is folded from an end of the base portion. The base portion of the positive-electrode current collector is connected to a positive electrode terminal, and the tab connection portion of the positive-electrode current collector is connected to the positive-electrode tab group. A fuse portion is formed in the positive-electrode current collector, and a first-insulator second region of a first insulator, which is connected to an inner insulator, is disposed between the base portion and the tab connection portion.