| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery, of which the durability against high-rate charge and discharge is enhanced.SOLUTION: A nonaqueous electrolyte secondary battery comprises: a wound electrode body arranged by winding a positive electrode sheet 220 and a negative electrode sheet 240 which are put together with separator sheets 262 and 264 interposed between the positive electrode sheet 220 and the negative electrode sheet 240; a battery case in which the wound electrode body is housed; and a nonaqueous electrolyte filled in the battery case. The separator sheets 262 and 264 each have a filler layer 266 on a surface thereof; the filler layer includes an inorganic filler and a binder. The binder included in opposing end portions E1 and E2 of the filler layer 266 in a direction of the winding axis of the wound electrode body is larger than the binder included in an intermediate portion C of the filler layer 266 other than the end portions E1 and E2 in the degree of being swelled by the nonaqueous electrolyte. |
