COMPLEX LITHIUM METAL OXIDES WITH ENHANCED CYCLE LIFE AND SAFETY AND A PROCESS FOR PREPARATION THEREOF

摘要

This invention relates to complex lithium metal oxides, which are cathode active materials of a lithium or lithium ion secondary battery with enhanced cycle life and safety, and a process for preparation thereof. The core particles are complex lithium metal oxides capable of absorbing, storing and emitting lithium ions, and a coating layer comprised of amorphous complex lithium cobalt oxides that are formed on the surface of the core particle, which is structurally stable and inactive with electrolytes. Because the amorphous complex lithium cobalt oxides are inactive with electrolytes, the oxides stabilize the surface structure of the complex lithium metal oxide and improve on high temperature storage properties, as well as safety and cycle life.