| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a sealed battery capable of preventing reduction of battery performance or reduction of overcharge resistance by suppressing deposition of lithium.SOLUTION: A lithium ion secondary battery 100 (sealed battery) comprises: a wound electrode body 110 which is formed by overlapping and winding a positive electrode plate 130 and a negative electrode plate 120 while interposing a separator 150 therebetween, the wound electrode body 110 including a planar part 111 in an outer circumferential surface 110a in a winding axis direction; and a battery case 180 accommodating the wound electrode body therein. The battery case includes, in a long-side sidewall part 181c (front sidewall part 181ca and rear sidewall part 181cb) opposing the planar part 111, a softened part (contact part 184) which is softened more than another portion (non-contact part 185). The softened part (contact part 184) is located at a position in contact with the planar part 111 in the long-side sidewall part 181c (front sidewall part 181ca and the rear sidewall part 181cb) of the battery case.</p> |
