▎ 摘　　要

NOVELTY - Cathode active material is prepared by dispersing graphene or oxidized graphene and lithium iron phosphate into water solution to obtain cathode active material. USE - Cathode active material for lithium-ion secondary battery (claimed). ADVANTAGE - The cathode active material has high capacity, excellent charging-discharging cycle property and stability. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method for preparing cathode active material, which involves dispersing graphene or oxidized graphene and lithium iron phosphate into water solution to obtain a mixture, stirring the obtained mixture for 0.5-2 hours, drying the stirred mixture to obtain a material and annealing the material at high temperature to obtain cathode active material; and (2) a lithium-ion secondary battery, which comprises an anode plate, a cathode plate, an isolation film, non-water electrolyte and cathode active material.