NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

To improve charge and discharge cycle characteristics of a nonaqueous electrolyte secondary battery which uses silicon and silicon oxide as negative electrode active materials. In one embodiment of the nonaqueous electrolyte secondary battery of the present invention, a sheet-like negative electrode, in which a negative electrode active material layer containing a composite of silicon and silicon oxide is formed on a negative electrode collector, is arranged so as to face a sheet-like positive electrode, in which a positive electrode active material layer is formed on a positive electrode collector, with a separator being interposed therebetween. The peripheral portion of the negative electrode active material layer is arranged inside the peripheral portion of the positive electrode active material layer. When the charge capacity of the positive electrode is represented by a, the charge capacity of the negative electrode is represented by b, and b/a = c, the following relation 1.00 < c is satisfied.