HIGH-CAPACITY CATHODE MATERIAL FOR NONAQUEOUS LITHIUM SECONDARY BATTERY USING SPHERICAL TRANSITION METAL COMPOSITE CARBONATE CONTAINING NANO-SIZED TITANIUM DIOXIDE, AND PREPARATION METHOD THEREFOR

摘要

The present invention relates to a cathode material for a nonaqueous lithium secondary battery using a spherical transition metal composite carbonate, and a preparation method therefor, wherein the electrochemical activity of a final cathode material is improved by preparing a spherical transition metal composite carbonate in which a nano-sized titanium dioxide is uniformly contained, by using liquid phase precipitation, thereby implementing a high capacity of at least 200 mAh/g. According to the present invention, it is possible to prepare a spherical transition metal composite carbonate having a particle size of 5-25 μm by precipitating a cobalt raw material, a nickel raw material, a manganese raw material, a carbonic acid group raw material, a dissimilar metal raw material for substitution, and an ammonia raw material so as to have a composition ratio represented by Ni_xCo_yMn_1-x-y-zTi_zCO₃ (wherein 0.0x≤0.3, 0.0≤y0.2, 0.5≤1-x-y-z, and 0z0.1). In addition, it is possible to prepare a spherical Li-rich cathode raw material having a primary particle size of 200 nm or more and capable of implementing a capacity of 200 mAh/g or more at 0.5 C by mixing and heat treating the prepared transition metal composite carbonate and a lithium raw material.