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

A positive active material for a rechargeable lithium battery includes nickel-based lithium transition metal oxide secondary particles, in which a plurality of primary particles are aggregated. The primary particles include polycrystalline primary particles composed of 2 to 10 single crystals, and each of the single crystals has a particle diameter of about 0.5 μm to about 3 μm.