A CATHODE MATERIAL FOR LITHIUM SECONDARY BATTERIES WITH NON-AQUEOUS ELECTROLYTE, A PROCESS FOR PREPARING THE CATHODE MATERIAL AND LITHIUM SECONDARY BATTERY CONTAINING THE SAME

摘要

Provided is a positive electrode active material for a lithium secondary battery with a non-aqueous electrolyte, which enhances battery capacity, is improved in cycle characteristics, and has excellent thermal safety owing to low reactivity with an electrolytic solution at high temperature. The positive electrode active material for a lithium secondary battery with a non-aqueous electrolyte comprises at least one metal selected from the group consisting of Al, Mg, Sr, Ca, P, Pb, Y, and Zr distributed on the surface of a lithium nickel cobalt manganese composite metal oxide represented by a formula 1 which is Li_aNi_1-(v+w+x+y+z)Mn_vCo_wM_xM'_yM"_zO2, wherein a content of unreacted sulfur on the surface is 1000ppm or less. In the formula 1, M, M', and M" are independently one or more selected from the group consisting of Al, Mg, Sr, Ca, P, Pb, Y, and Zr, wherein 0.9=a=1.1, 0.295=1-(v+w+x+y+z)=0.85, 0.05=v=0.35, 0.10=w=0.35, and 0.015=x+y+z=0.03.