▎ 摘　　要

NOVELTY - Manufacturing negative active material, comprises preparing graphite particles, silicon-carbon nanotube composite, and nanoporous graphene, coating the silicon-carbon nanotube composite on the surface of graphite particles through mechanochemical reaction to form shell, and forming coating layer by coating nanoporous graphene on surface of the silicon-carbon nanotube composite. The negative active material has core made of graphite particles, shell coated on surface of the core and made of a silicon-carbon nanotube composite and a coating layer coated on the surface of the shell and made of nanoporous graphene. The nanoporous graphene is obtained by preparing graphene oxide in which the metal oxide is dispersed by growing metal oxide on surface of graphene, reducing graphene oxide in which metal oxide is dispersed to prepare graphene in which the metal particles are dispersed, and thermally decomposing graphene in which metal particles are dispersed to remove metal particles. USE - The negative electrode active material is useful as negative electrode material for secondary battery. ADVANTAGE - The negative electrode active material improves output of a secondary battery compared to a conventional negative active material by coating a silicon-carbon nanotube composite and graphene on the surface of graphite particles, and has mechanochemical reaction.