In this paper, we report the electrochemical characteristics of a novel cathode material, Li 2 CoPO 4 F, prepared by solid-state reactions. The solid-state reaction mechanism involved in synthesizing the Li 2 CoPO 4 F also is analyzed in this paper. When cycled between 2.0V and 5.0V during cyclic voltammetry measurements, the Li 2 CoPO 4 F samples present one, fully reversible anodic reaction at 4.81V. When cycled between 2.0V and 5.5V, peaks occurring at 4.81V and 5.12V in the first anodic scan evolved to one broad oxidative, mound-like pattern in subsequent cycles. Correspondingly, the X-ray diffraction (XRD) pattern of the Li 2 CoPO 4 F electrode discharged from 5.5V to 2.0V is slightly different from the patterns exhibited by a fresh sample and the sample discharged from 5.0V to 2.0V. This difference may correspond to a structural relaxation that appears above 5V. In the constant current cycling measurements, the Li 2 CoPO 4 F samples exhibited a capacity as high as 109mAhg −1 and maintained a good cyclability between 2.0V and 5.5V vs. Li/Li + . XRD measurements confirmed that the discharged state is Li 2 CoPO 4 F. Combining these XRD results and electrochemical data proved that up to 1mol Li + is extractable when charged to 5.5V.