| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery in which electrical resistance between a negative current collector and the bottom of case is low. SOLUTION: A cylindrical bottomed case 20 of this battery is made of a metal plate, has a cylindrical part 21 whose one end unitedly forms a bottom 22, the bottom 22 is made flat so as to preferably have a flatness of 0.3 mm (the height difference between micro-projections and micro-recesses is 0.3 mm) or less. A negative current collector 6 is arranged on the inside of the bottom, welded to a negative electrode 8 and connected to the spirally wound negative electrode 8. |
