Nanostructured LiFePO4 powder with a narrow size distribution (~100nm) has been obtained using a sol–gel method with graphene as coating, and applied in high efficiency lithium-ion battery cathode. During preparation of LiFePO4 precursor, Nb5+ and Ti4+ were added to get a sufficient and homogenous doping. Through X-ray diffraction (XRD), scanning electron microscope (SEM), charge/discharge tests, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) characterization, the influence of supervalent metal doping and graphene coating on the structure and performance of LiFePO4 was studied. Li0.99Nb0.01Fe0.97Ti0.03PO4/graphene cathode delivers a discharge capacity (163mAhg−1 at 0.1C) close to the theoretical value with excellent capacity retention (99.1% after 30cycles) and rate capability (140mAhg−1 after discharged at 0.1C, 2C, 5C stepwise). The results indicate that both ion-doping and graphene-coating are effective to improve the electrochemical performance of lithium ion battery.