| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a secondary battery having high reliability while securing sufficient capacity. <P>SOLUTION: This is equipped with a battery element 20 having a laminating structure of a positive electrode 21 and a negative electrode 22, and a flat state cross section including an opposing pair of flat parts 20S, and an exterior can 11 to house this battery element 20. The negative electrode 22 contains at least one kind of tin and silicon as an active material, or metal lithium, and the positive electrode 21 is comprised of a first member 211 and a second member 212 which were divided in winding direction R and insulated from each other. By this, compared with a case that the positive electrode 21 is not divided, stress formed interior the battery element 20 by swelling and contraction accompanied with charge and discharge is relaxed, and calorific values at the time of a short circuit interior the battery element 20 becomes smaller. <P>COPYRIGHT: (C)2009,JPO&INPIT |
