| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a battery that can suppress cracks and breaks even in a thick positive electrode. <P>SOLUTION: The battery comprises a roll 20 of the positive electrode 21 and a negative electrode 22 stacked with a separator 23 in between. The positive electrode 21 has a double-side active material region 21D having an outer positive active material layer 21B and an inner positive active material layer 21C on a positive collector 21A, and the inner positive active material layer 21C is thinner than the outer positive active material layer 21B. The roll center is a double-side exposure region 21E exposing the positive collector 21A, and has a lead 25 attached. An outer active material region 21F having only the outer positive active material layer 21B is formed over the lead 25 between the double-side active material region 21D and the double-side exposure region 21E. This relaxes steps of the lead 25 to suppress cracks. <P>COPYRIGHT: (C)2008,JPO&INPIT |
