POSITIVE ELECTRODE ACTIVE MATERIAL FOR RECHARGEABLE LITHIUM BATTERY, METHOD OF PREPARING THE SAME, AND RECHARGEABLE LITHIUM BATTERY

Provided are a positive electrode active material for a rechargeable lithium battery, a method of preparing the same, and a rechargeable lithium battery including the same. The positive electrode active material for a rechargeable lithium battery includes a lithium nickel-based composite oxide, wherein the positive electrode active material is in a form of a secondary particle in which a plurality of primary particles are aggregated together and at least a portion of the primary particles are radially arranged, the secondary particle includes an inner portion and an outer portion, the inner portion of the secondary particle is a region from a center of the secondary particle to 50±5 length % of the total distance from the center to the surface of the secondary particle, and is a region in which primary particles and pores are irregularly arranged.