Lithium-nickel-cobalt-manganese-fluorine-containing composite oxide, method for producing the same, and lithium secondary battery using the same

摘要

A positive electrode active material for a lithium secondary battery having a wide usable voltage range, high charge / discharge cycle durability, high capacity, and high safety and availability is obtained. General formula LipNixMn1-xyCoyO2-qFq (where 0.98 ≦ p ≦ 1.07, 0.3 ≦ x ≦ 0.5, 0.1 ≦ y ≦ 0.38, 0 q ≦ 0.05) A lithium-nickel-cobalt-manganese-fluorine-containing composite oxide having an R-3m rhombohedral structure represented by the formula (2) in X-ray diffraction using Cu-Kα rays of 65 ± 0.5 °. Lithium-nickel-cobalt-manganese-fluorine-containing composite oxide particles characterized in that the half-value width of the diffraction peak of (110) plane is 0.12-0.25 ° are used as the positive electrode active material.