| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery, the durability against high rate charge and discharge of which is improved.SOLUTION: A nonaqueous electrolyte secondary battery 100 including a wound electrode body 200 and a nonaqueous electrolyte 90 and a battery case 300 is provided. The wound electrode body 200 includes a positive electrode sheet 220, a negative electrode sheet 240, and separator sheets 260, 280. The separator sheets 260, 280 include a base material layer and a heat-resistant porous layer, where the heat-resistant porous layer contains a filler and a binder. The solubility parameter of the binder located in the winding center of the wound electrode body 200 is closer to that of the nonaqueous electrolyte 90, compared with the solubility parameter of the binder located in the outer periphery of winding.SELECTED DRAWING: Figure 1 |
