| 摘要 |
PROBLEM TO BE SOLVED: To provide: a negative electrode active material for a lithium ion secondary battery, which is superior in cycle characteristic while keeping a high initial efficiency and a battery capacity; and a method for manufacturing such a negative electrode active material.SOLUTION: A method for manufacturing a negative electrode active material comprises the steps of: doping surfaces of silicon microparticles with at least one kind of metal, provided that the average particle diameter (D50) of the silicon microparticles measured by a particle size distribution meter according to laser diffraction or dynamic light scattering is 0.3 μm or less; mixing together the silicon-based microparticles which have a silicon single phase peak according to XRD measurement, amorphous carbon and/or microcrystal carbon and as required, graphite; granulating and compacting the resultant mixture; performing pulverization and conglobation thereof, thereby forming complex particles; and sintering the resultant material in an inert gas atmosphere.SELECTED DRAWING: Figure 1 |
