A conductive lead 21 or 22 welded to a positive electrode 11 or a negative electrode 12 protrudes from the upper surface side and the lower surface side of an electrode group 10. The conductive leads 21 and 22 have spiral shape portions 21b and 22b and end portions 21c and 22c for welding, respectively. The end portion 21c for welding of the conductive lead 21 is welded to a lid unit 5, and the end portion 22c for welding of the conductive lead 22 is welded to a can bottom 203 of a battery can 2. The end portion 22c for welding of the conductive lead 22 is positioned corresponding to a hollow portion 15a of an axial core 15.