The invention provides an active material for a nonaqueous
electrolyte secondary battery, a method for production of the active material and the nonaqueous
electrolyte secondary battery using the active material, the active material excellent high-rate
discharge characteristics. The active material for a nonaqueous
electrolyte secondary battery includes a
lithium-
transition metal composite oxide which has an alpha-NaFeO2 -type
crystal structure and of which the average composition is represented by the composition formula of Li1+[alpha]Me1-[alpha]O2 (Me is a
transition metal containing Co, Ni and Mn; and alpha > 0), wherein the
lithium-
transition metal composite oxide is a particle having a core and a coated part, the
cobalt concentration of the coated part is higher than the
cobalt concentration of the core, the
manganese concentration of the coated part is lower than the
manganese concentration of the core, and the ratio of
cobalt present in the coated part is 3 to 10% in terms of a
molar ratio based on the amount of the transition
metal present in the core. In addition, the method for production of the active material of the nonaqueous electrolyte secondary battery is characterized by enabling cobalt-containing compounds, cobalt-
nickel-containing compounds and cobalt-
nickel-
manganese-containing compounds with more cobalt than manganese in a
molar ratio to coat co-precipitated precursor core particles of transition
metal compounds containing cobalt,
nickel and manganese and being with more manganese than cobalt in the
molar ratio, mixing the co-precipitated precursor core particles and
lithium compounds, and then firing.