POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, METHOD FOR PRODUCTION THEREOF, AND LITHIUM SECONDARY BATTERY

摘要

Disclosed is a positive electrode active material for a lithium secondary battery, which can prevent the occurrence of gelatinization during kneading with a binder resin in the production of a positive electrode material, and which has excellent coatability. Specifically disclosed is a positive electrode active material for a lithium secondary battery, which comprises a lithium composite oxide represented by the general formula (1) and a Ca atom contained in the lithium composite oxide, wherein the ratio of (a) the intensity of a CaO-derived diffraction peak appearing at 2? = 37.4 ± 0.2° to (b) the intensity of a diffraction peak appearing at 2? = 18.7 ± 0.2° (i.e., a (b/a) ratio) is 10 to 150 as measured by the X-ray diffraction analysis of the positive electrode active material using a Cu-Ka line as the line source. LixNi1-y-zCoyMezO2 (1) wherein Me represents a metal element having an atomic number of 11 or higher excluding Co and Ni; and x, y and z meet the requirements expressed by the following formulae: 0.98 = x = 1.20, 0 < y = 0.5, and 0 < z = 0.5, provided that y + z < 1.