| 摘要 |
PROBLEM TO BE SOLVED: To provide a secondary battery in which a current collector jointed to an electrode body being a power generation element can be welded to the bottom of a battery can with a large jointing area, capable of reducing the internal resistance of the battery. SOLUTION: The secondary battery is constructed by housing a wound-up electrode body 4 inside a battery can 1, in which a sealing plate 2 is fixed at the opening part of a bottomed cylinder 11. A positive electrode current collector 51 is connected to the end fringe of the core 45 on the positive electrode side of the wound-up electrode body 4, and a negative electrode current collector 5 is connected to the end fringe of the core 47 on negative electrode side. The surface of the negative electrode current collector 5 is welded to the bottom of the bottomed cylindrical body. A projection 14 protruding toward the inside of the battery can 1 is formed at the bottom of the bottomed cylinder 11 and a recessed face 56 which is engaged with the projection 14 is formed on the surface of the negative electrode current collector 5, and a resistance welding is applied to the engaging portion of the recessed face 56 and the projection 14. COPYRIGHT: (C)2006,JPO&NCIPI |
