SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a secondary battery that can occlude or release lithium efficiently in graphite as an active material, and provide a secondary battery with high reliability by suppressing the variation in amount of occlusion and release of lithium relative to the graphite as the active material.SOLUTION: A secondary battery includes a positive electrode and a negative electrode containing a current collector and graphite provided on the current collector. The graphite includes a plurality of graphene layers, and the surfaces of the graphene layers are arranged approximately along the direction of the electric field formed between the positive electrode and the negative electrode.