A method for preparing lithium transitional metal oxides, comprises the steps of: preparing a carbonate precursor using the following substeps: forming a first aqueous solution containing a mixture of at least two of the ions of the following metal elements (“Men+”): cobalt (Co), nickel (Ni), and manganese (Mn); forming a second aqueous solution containing ions of CO32−; and mixing and reacting the first solution and the second solution to produce the carbonate precursor, Ni1-x-yCoxMnyCO3; and preparing the lithium transition metals oxide from the carbonate precursors using the following substeps: evenly mixing Li2CO3 and the carbonate precursor; calcinating the mixed material in high temperature; and cooling and pulverizing the calcinated material to obtain the lithium transition metal oxide, Li Ni1-x-yCoxMnyO2.