NEGATIVE ACTIVE MATERIAL FOR RECHARGEABLE LITHIUM BATTERY, METHOD OF PREPAREING THE SAME AND RECHARGEABLE LITHIUM BATTERY INCLUDING THE SAME

摘要

PURPOSE: An anodal active material for lithium secondary battery is provided to improve lifetime property and high capacity of a lithium secondary battery. CONSTITUTION: An anodal active material for lithium secondary battery comprises: silicon oxide particle having Si and O phases. The silicon oxide particle has a concentration gradient that an atomic percentage of the Si phase decreases, and an atomic percentage of the O phase increases becoming closer from the particle surface to the center of the particle. The distance between the surface of the silicon oxide particle and the depth where the atomic percentage of Si phase is 55, is 2-20% of the silicon oxide particle diameter.