| 摘要 |
A coin-shaped battery comprises: a power generating element including a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and an electrolyte; and an outer package body for housing the power generating element. The outer package body comprises: a cylindrical battery case having a bottom surface portion and a first side wall rising from the rim of the bottom surface portion; a sealing cap having an upper surface portion and a second side wall extending from the rim of the upper surface portion to the inside of the first side wall; and a gasket, at least a part of which is interposed between the first side wall and the second side wall. The sealing cap comprises: a first curved portion formed at the boundary between the upper surface portion and the second side wall; a second curved portion formed following the first curved portion; a third curved portion formed following the second curved portion; and a falling portion formed following the third curved portion. In the sealing cap, the ratio (R1/R2) between the curvature radius (R1) on the outer surface side of the first curved portion and the curvature radius (R2) on the outer surface side of the second curved portion is 0.22 to 1.88. |
