| 摘要 |
A battery includes a spirally wound electrode body in which a cathode and an anode are layered with a separator in between and spirally wound. The spirally wound electrode body is attached with at least one lead on the spirally-winding center side. The cathode has a cathode current collector having a pair of opposed faces, an outer-face cathode active material layer provided on the spirally-winding outer face side of the cathode current collector, and an inner-face cathode active material layer provided on the spirally-winding inner face side thereof. A thickness of the inner-face cathode active material layer is smaller than a thickness of the outer-face cathode active material layer. An outer face active material region provided with only the outer-face cathode active material layer is formed to be overlapped with the lead on the spirally-winding center side of the cathode. |
