Citrate-gel-combustion Synthesis of LiCoVO_4 as Novel High-voltage Cathode Material for Li-ion Batteries

A new method by combining Chimie Douce method with sol-gel route and using citrate as complex reagent was introduced for preparing inverse spinel LiCoV04 as novel high-voltage cathode material for Li-ion batteries. Investigations were conducted by XRD, DSC and TG, IR, Raman, SEM and EDAX, and electrochemical techniques. The results of XRD and thermal analysis show the high crystalline LiCoV04 with high phase purity are formed at 450℃. The results of the IR and Raman investigations show the band located at -820cm-1 corresponding to the stretching vibration mode with the A1 symmetry, whereas the band situated at -335cm-1 corresponding to the bending mode of the VO4 tetrahedron with E symmetry. The SEM and EDAX results show that the average diameter of the original particles is 300nm and the distributions of particle diameter and elements are even. Electrochemical measurement shows that the initial charge capacity is 160mAh·g-1 with the platform voltage of 4.8V and its discharge capacity is 152mAh·g-1.