The present invention provides a powderous
lithium transition metal oxide with the composition as represented by the below Formula and prepared by
solid state reaction in air from a mixed
transition metal precursor and Li2CO3, with being practically free of Li2CO3
impurity: LixMyO2 wherein M=M′l-kAk, where M′=Nil-a-b(Ni1 / 2Mn1 / 2)aCob on condition of 0.65≦a+b≦0.85 and 0.1≦b≦0.4; A is a
dopant; and 0≦k≦0.05; and x+y=2 on condition of 0.95≦x≦1.05. The Ni-based
lithium transition metal oxide according to the present invention has a well-
layered structure, and also improved safety,
cycling stability and stability against aging and low gas evolution during storage, when used as an active material for
cathode of
lithium secondary batteries, because it has a high
sintering stability and is substantially free of soluble bases. Moreover, the lithium transition
metal oxide of the present invention can be prepared by a low-cost process using a mixed transition
metal precursor and Li2CO3 as raw stocks and under relatively unrestricted conditions.