NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

A non-aqueous electrolyte secondary battery, wherein a negative electrode includes a negative electrode mixture layer having a thickness T and a negative electrode current collector, the negative electrode active material includes carbon and Si-containing materials, wherein when the negative electrode mixture layer is divided into a first region having a thickness of T/2 on the surface side of the negative electrode and a second region having a thickness of T/2 on the negative electrode collector side, a mass ratio of the first to the second composite material contained in the first region is >1, a mass ratio of the first composite to the second composite material contained in the second region is