| 摘要 |
PROBLEM TO BE SOLVED: To enhance the degree of freedom in battery design even when the winding number of an electrode body is reduced by 2-3 turns and minimize the clearance between the electrode body and a battery can to allow a higher capacity. SOLUTION: The winding center 4a of an electrode body 4 is shifted from the center of a battery can 5, whereby the clearance between the electrode body 4 and the battery can 5 is reduced. A thin part is provided in part of a positive electrode 1 or negative electrode 2, and this thin part is arranged in any position in the direction where the winding end of the electrode body 4 is present, or the direction where the sectional diameter of the cavity part in the central part of the electrode body 4 is the longest is not conformed to the direction where the winding end part of the electrode body 4 is present, whereby the ratio of shortest diameter to longest diameter of the section of the electrode body 4 approaches to 1. |
