Nonaqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery comprising a spirally wound electrode body in which a positive electrode and a negative electrode are spirally wound with a separator interposed therebetween,

• wherein the negative electrode includes a negative electrode current collector, a first negative electrode mixture layer disposed on a first surface of the negative electrode current collector, and a second negative electrode mixture layer disposed on a second surface of the negative electrode current collector, the first surface and the second surface facing outward and inward of the electrode body, respectively,
• wherein the first negative electrode mixture layer includes a Si active material composed of at least one of Si and a Si-containing material,
• wherein a content of the Si active material in terms of Si is lower in a portion of the first negative electrode mixture layer which faces the negative electrode current collector in a thickness direction of the first negative electrode mixture layer, than in a portion of the first negative electrode mixture layer which faces a surface of the first negative electrode mixture layer in the thickness direction,
• wherein the second negative electrode mixture layer includes the Si active material, and
• wherein the content of the Si active material in terms of Si is lower in a portion of the second negative electrode mixture layer which faces a surface of the second negative electrode mixture layer in a thickness direction of the second negative electrode mixture layer, than in a portion of the second negative electrode mixture layer which faces the negative electrode current collector in the thickness direction.