Nonaqueous electrolyte secondary battery having separators with base material and heat-resistant layer on coiling outer peripheral side

Abstract

Provided is a nonaqueous electrolyte secondary battery 10 which, in cases where separators 70 each having a heat-resistant layer 74 on only one face thereof are used, has an excellent thermal stability and thus a higher safety and reliability when the battery 10 reaches a high temperature. Such a nonaqueous electrolyte secondary battery 10 includes a positive electrode 30 in which a positive electrode active material layer 34 is provided on both faces of a positive electrode current collector 32, a negative electrode 50 in which a negative electrode active material layer 54 is provided on both faces of a negative electrode current collector 52, at least two separators 70 each having a heat-resistant layer 74 on one face of a base material 72, and an electrolyte. The nonaqueous electrolyte secondary battery has an electrode assembly 20 in which the positive electrode 30 and the negative electrode 50 are stacked on top of one another with the separators 70 interposed therebetween. The at least two separators 70 are disposed in such a way that, for each separator, the heat-resistant layer 74 is positioned on the same side with respect to the base material 72 in the stacking direction.

Dependencies are inferred from the claim text.