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

摘要

The present invention relates to a negative electrode active material for a lithium secondary battery, comprising: a carbon material; and a coating layer formed on the surfaces of carbon material particles and made of a plurality of Sn-based domains having a mean diameter of 1 µm or smaller. The present invention also relates to a method for preparing the negative electrode active material. The negative electrode active material of the present invention comprising the Sn-based domain coating layer formed on the surface of the carbon material may relieve stress caused by volume expansion resulting from alloying lithium and Sn. The method for preparing the negative electrode active material according to the present invention may enable the thickness of the coating layer to be easily adjusted.