▎ 摘　　要

NOVELTY - Silicon-based active material comprises porous silicon particles derived from diatom, where the silicon particles have a doped layer doped with a metal oxide and a coating layer coated with carbon or graphene on the doped layer. USE - The active material is useful for a negative electrode of a lithium-ion battery (claimed). ADVANTAGE - The active material has excellent structural stability and excellent energy storage capacity per volume; increases the charging capacity; is capable of suppressing the expansion of silicon particles, without breaking the particles even during continuous charging and discharging of lithium ions. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for producing silicon-based active material comprising preparing porous silicon particles derived from diatoms, forming a doping layer by doping a metal oxide on the surface of the prepared silicon particles and forming a coating layer by coating carbon or graphene on the formed doping layer.