Non-aqueous electrolyte secondary battery

Abstract

The present invention is made to improve charge-discharge cycle performances under high temperature environment in a non-aqueous electrolyte secondary battery using a negative electrode containing a negative electrode active material of particulate silicon and/or silicon alloy and a binding agent. A non-aqueous electrolyte secondary battery according to the present invention includes a positive electrode 11, a negative electrode 12, a separator 13, and a non-aqueous electrolyte, wherein the negative electrode includes a negative electrode active material containing particulate silicon and/or silicon alloy and a binding agent, and the non-aqueous electrolyte contains fluorinated cyclic carbonate and a prescribed diisocyanate compound, and when Li storage volume per unit area of the negative electrode of the non-aqueous electrolyte secondary battery under charging condition is determined as A and the theoretical maximum Li storage volume per unit area of the negative electrode is determined as B, a utilizing rate (%) of negative electrode which is expressed by (A/B)×100 is 45% or less.

Dependencies are inferred from the claim text.