Low-temperature synthesis of Cu-doped Li1.2V3O8 as cathode for reversible lithium storage

Li-1 .2V3O8 and Cu-doped Li1.2V3O8 were prepared at a temperature as low as 300 A degrees C by a sol-gel method. The structure, morphology, and electrochemical performance of the as-prepared samples were characterized by means of X-ray diffraction, scanning electron microscopy, electrochemical impedance spectroscopy, and the galvanostatic discharge-charge techniques. It is found that the Cu-doped Li1.2V3O8 sample exhibits less capacity loss during repeated cycling than the undoped one. The Cu-doped Li1.2V3O8 sample demonstrates the first discharge capacity of 275.9 mAh/g in the range of 3.8-1.7 V at a current rate of 30 mA/g and remains at a stable discharge capacity of 264 mAh/g within 30 cycles. Furthermore, the possible role that copper plays in enhancing the cycleability of Li1.2V3O8 has also been elucidated.