Template free synthesis of LiV₃O₈nanorods as a cathode material for high-rate secondary lithium batteries

Abstract

A novel, template-free, low-temperature method has been developed to synthesize LiV3O8 cathode material for high-power secondary lithium (Li) batteries. The LiV3O8 prepared using this new method was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The thermal decomposition process was investigated using thermogravimetric (TG) and differential thermal analysis (DTA). LiV3O8 produced using the conventional high-temperature fabrication method also was analyzed. The electrochemical performances and the effects of synthesis temperature on our LiV3O8 and the conventionally produced LiV3O8 were compared. The LiV3O8 produced using our new method has a nanorod crystallite structure composed of uniform, well-separated particles with diameters ranging from 30 to 150 nm. The TEM work reveals the stacking defaults within the nanorod structures, which would facilitate the electron transportation during the insertion and removal process of lithium ions. It delivers specific discharge capacities of 320 mAh g−1 and 239 mAh g−1 at current densities of 100 mA g−1 and 1 A g−1, respectively. It also exhibits excellent capacity retention with only 0.23% capacity fading per cycle. This excellent electrochemical performance can be attributed to the superior structural characteristics of our material, and the results of our study demonstrate that LiV3O8 nanorod crystallites produced by this new thermal decomposition method are promising cathode materials for high-power Li batteries.