| 摘要 |
PROBLEM TO BE SOLVED: To provide a secondary battery which can use a copper lead as a lead for high output by eliminating the difficulty of resistance welding when copper is used as the lead, and a manufacturing method therefor. SOLUTION: In a lithium ion secondary battery using a copper foil as current- collecting foil of a negative electrode, a copper lead 2 is used as a lead from the copper foil, and this copper lead 2 is welded to a battery can 8 by resistance welding. Since the copper lead 2 is used, it is suitable for a battery whose maximum electric current is not less than 20 A. In this case, the copper lead 2 is welded to the battery can 8 by resistance welding to heat them by carrying an electric current, by sandwiching the copper lead 2 and the battery can 8 between a first welding electrode bar 3 and a second welding electrode bar 4 in which metal 5 having high electrical resistance is attached to its tip. |
