Phospho-olivine cathode materials were prepared by hydrothermal reaction. Carbon black was added to enhance the electrical conductivity of . The structural and morphological performance of and -C powders were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). /Li and -C/Li cells were characterized electrochemically by cyclic voltammogram (CV), charge/discharge experiments and ac impedance spectroscopy. The results showed that the discharge capacity of /Li cell was 147 mAh/g at the first cycle and 118 mAh/g after 30 cycles, respectively. The discharge capacity of -C/Li cell with 5 wt% carbon black was the largest among -C/Li cells, 133 mAh/g at the first cycle and 128 mAh/g after 30 cycles, respectively. It was demonstrated that cycling performance of -C/Li cell with 5 wt% carbon black was better than that of /Li cell.