Patent ID: 11456489

Abstract:
The present invention provides a technology that allows supplying stably a nonaqueous electrolyte secondary battery having a high capacity retention rate and being excellent in resistance to deterioration. The nonaqueous electrolyte secondary battery disclosed herein is provided with a wound electrode body resulting from winding a stack 10 having a stacking of a positive electrode 50 and a negative electrode 60 across separators 70. The positive electrode 50 has a foil-shaped positive electrode collector 52 and a positive electrode mix layer 54. Each separator 70 has a resin substrate layer 72 and a heat resistance layer 74. In the nonaqueous electrolyte secondary battery disclosed herein, the peel strength of a boundary between the resin substrate layer and the heat resistance layer is 16 N/m or more and 155 N/m or less, and the density of the positive electrode mix layer is 2.3 g/cc or more and 2.6 g/cc or less. In this the nonaqueous electrolyte secondary battery, sufficient flexibility of the stack 10 as a whole can be secured even when using high-peel strength separators 70 in order to increase resistance to deterioration. Drops in production efficiency can be suitably suppressed as a result.