Significant improvement of electrochemical performance of Cu-coated LiVPO 4 F cathode material for lithium-ion batteries

In this paper, we reveal that the intrinsic low electronic conductivity of the pristine LiVPO 4 F is overcome with conductive Cu-coating. The existence of nano-Cu is confirmed with X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The morphology and particle size are observed by scanning electron microscopy (SEM). Galvanostatic charge/discharge test indicates that Cu coating is effective to improve the discharge capacity, cycle performance and rate capability. Analysis of electrochemical impedance spectra (EIS) shows that the addition of nano-Cu markedly decreases the charge transfer resistance of the pristine LiVPO 4 F electrode. Graphical Abstract Nano-Cu coating on the surface of pristine LiVPO 4 F particles is successfully synthesized for the first time via a soft chemical route with mechanical activation assistance. The effect of Cu coating on the crystalline structure, morphology and electrochemical performance of the pristine sample has been investigated in detail.