POSITIVE ELECTRODE ACTIVE MATERIAL AND METHOD FOR PRODUCING POSITIVE ELECTRODE ACTIVE MATERIAL

The present invention relates to: a positive electrode active material comprising a single particle-type lithium transition metal oxide having a nickel content of 80 mol% or more among metals excluding lithium and consisting of 1 to 30 nodules, wherein a cation mixing ratio satisfies a specific formula; and a method for producing same, the method comprising: a first step of preparing a mixture by mixing an anhydrous lithium raw material and a transition metal precursor oxide having a nickel content of 80 mol% or more among the total metals; and a second step of preparing a single particle-type lithium transition metal oxide consisting of 1 to 30 nodules by sintering the mixture, wherein the ratio of the D50 of the anhydrous lithium raw material to the D50 of the transition metal precursor oxide is 4 to 20.