▎ 摘　　要

NOVELTY - A graphene/lithium-iron phosphate composite comprises graphene or graphene oxide and lithium-iron phosphate. The mass ratio of graphene and lithium-iron phosphate is 1:100-1:10. The mass ratio of graphene oxide and lithium-iron phosphate is 1:50-1:5. USE - Graphene/lithium-iron phosphate composite is used as active material for positive electrode of high-performance lithium-ion secondary battery (claimed). ADVANTAGE - The lithium-ion secondary battery containing active material (graphene/lithium-iron phosphate composite) has high capacity, excellent rate discharge property and cyclic property, and is prepared by simple method with high productivity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of graphene/lithium-iron phosphate composite. Predetermined amount of graphene or graphene oxide is uniformly mixed with iron-containing, lithium-containing and phosphorus-containing precursors by liquid-phase or solid-phase method, dried, and then annealing at high temperature, to obtain graphene/lithium-iron phosphate composite. The molar ratio of lithium, iron and phosphorus in iron-containing, lithium-containing and phosphorus-containing precursors is 1.00:0.95-1.05:0.95-1.05. The mass ratio of graphene and lithium-iron phosphate is 1:100-1:10. The mass ratio of graphene oxide and lithium-iron phosphate is 1:50-1:5; and (2) high-performance lithium-ion secondary battery, which has positive electrode, negative electrode, diaphragm placed between positive electrode and negative electrode, and non-aqueous electrolyte. The positive electrode contains active material (A) coated on positive electrode current collector. The active material (A) contains graphene or graphene oxide and lithium-iron phosphate. The mass ratio of graphene and lithium-iron phosphate is 1:100-1:10. The mass ratio of graphene oxide and lithium-iron phosphate is 1:50-1:5.