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.