Co-doped LiFe1−x Co x PO4/C (x =0, 0.005, 0.010, 0.020) composites were synthesized by oxalic acid-assisted sol–gel method and their electrochemical properties had been investigated in detail using galvanostatic charge/discharge, cyclic voltammograms (CVs) and electrochemical impedance spectra (EIS) tests. Co-doping benefited the transportation of Li+ and electrochemical conductivity which lead to the excellent high rate capability. The doped LiFe1−x Co x PO4/C with x =0.010 exhibited the best electrochemical properties, with discharge capacity of 114.8 and 104.2mAhg−1 at 10C and 20C, respectively.