NEGATIVE ELECTRODE FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

A non-aqueous electrolyte secondary battery including a silicon material as a negative electrode active material has good discharge rate characteristics. A negative electrode according to an exemplary embodiment includes a negative-electrode current collector and a negative-electrode mixture layer formed on the current collector. The negative-electrode mixture layer contains graphite and a silicon material. A first region that extends from the surface of the mixture layer remote from the negative-electrode current collector in the thickness direction of the negative-electrode mixture layer and has a thickness equal to 40% of the thickness of the mixture layer contains a larger amount of the silicon material than a second region that extends from the surface of the mixture layer adjacent to the negative-electrode current collector and has a thickness equal to 40% of the thickness of the mixture layer. The first region has a lower density than the second region.

主权项

1. A negative electrode for a non-aqueous electrolyte secondary battery, comprising:
a negative-electrode current collector; and a negative-electrode mixture layer formed on the current collector, wherein the negative-electrode mixture layer contains graphite and a silicon material, a first region that extends from a surface of the mixture layer remote from the negative-electrode current collector in a thickness direction of the negative-electrode mixture layer and has a thickness equal to 40% of a thickness of the mixture layer contains a larger amount of the silicon material than a second region that extends from a surface of the mixture layer adjacent to the negative-electrode current collector and has a thickness equal to 40% of the thickness of the mixture layer, and the first region has a lower density than the second region.