Lithium nickel containing composite oxide and manufacturing method thereof, and nonaqueous-electrolyte secondary battery

A cathode active material that is able to improve storage characteristics without deteriorating charging and discharging capacity is provided. By mixing lithium nickel containing composite oxide particles comprising a layered rock-salt type crystal structure, a lithium compound, and an alkali metal compound; calcining the mixed powder at a temperature range of 800° C. to 1000° C.; washing and removing alkali metal other than lithium; mixing washed calcined particles with a lithium compound again; calcining the mixture in an oxidizing atmosphere at a temperature range of 600° C. to 800° C., lithium nickel containing composite oxide comprising a layered rock-salt type crystal structure and a peak intensity ratio of (003) plane with respect to (104) plane of 1.2 or more that are obtained by X-ray powder diffraction using Cu-Kα ray as an X-ray source is obtained.