SECONDARY BATTERY AND MANUFACTURING METHOD OF THE SAME

A negative electrode and a secondary battery including the negative electrode are provided. A plurality of projections and depressions are provided in a negative electrode active material layer and a negative electrode current collector. The plurality of projections and depressions in the negative electrode active material layer absorb expansion of the negative electrode active material and suppress deformation thereof. The plurality of projections and depressions in the negative electrode current collector suppress deformation of the negative electrode current collector caused by expansion and contraction of the negative electrode active material.