▎ 摘　　要

NOVELTY - A negative electrode active material comprises a silicon-based compound (I), an amorphous carbon layer arranged on the silicon-based compound, a graphene layer arranged on the amorphous carbon layer, and a gap layer corresponding to a separated gap between the amorphous carbon layer and the graphene layer. USE - Active material is used for forming negative electrode of secondary battery (claimed) e.g. lithium-ion secondary battery used for portable computer, portable phone, and camera. ADVANTAGE - The negative electrode formed using the active material provides secondary battery having high capacity and energy density, and excellent charging/discharging property and durability. DETAILED DESCRIPTION - A negative electrode active material comprises a silicon-based compound of formula: SiOx (I), where x is 0.5-1.3, an amorphous carbon layer arranged on the silicon-based compound, a graphene layer arranged on the amorphous carbon layer, and a gap layer corresponding to a separated gap between the amorphous carbon layer and the graphene layer. An INDEPENDENT CLAIM is included for manufacture of negative electrode active material, which involves preparing silicon-based compound (I), arranging a polymer layer containing a polymer compound chosen from glucose, fructose, galactose, maltose, lactose, sucrose, phenol resin, naphthalene resin, polyvinyl alcohol resin, urethane resin, polyimide, furan resin, cellulose resin, epoxy resin, polystyrene resin, resorcinol resin, floroglucinol resin, coal pitch, petroleum pitch, and tar, on the silicon-based compound, arranging a metal catalyst layer on the polymer layer, heat-treating the silicon-based compound in which the polymer layer and the metal catalyst layer are arranged, and removing the metal catalyst layer.