NEGATIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, METHOD FOR PREPARING SAME, AND LITHIUM SECONDARY BATTERY COMPRISING SAME

摘要

The present invention relates to a negative electrode active material for a lithium secondary battery and a method for preparing the same, wherein the negative electrode active material contains porous polycrystalline silicon and the porous polycrystalline silicon includes pores positioned in grain boundaries, and thus, the negative electrode active material can internally absorb the volume change thereof to exhibit a buffer action at the time of charging or discharging, resulting in the improvement in lifespan characteristics of a negative electrode and a battery.