祝贺邵高琦等人的文章被J. Mater. Chem. A接受
Enhancing the Performance of Li3VO4 by Combining Nanotechnology and Surface Carbon Coating for Lithium Ion Batteries
Gaoqi Shao, Lin Gan, Ying Ma, Huiqiao Li* and Tianyou Zhai*
Keywords: Li3VO4, carbon-coated, nanosize, anode, lithium ion battery
Abstract: With a large capacity and low voltage, Li3VO4 has recently attracted much attention as a new insertion-type anode material for lithium-ion battery. However, the poor electronic conductivity of Li3VO4 leads to large amount addition of inactive conduct agents in the electrode, which definitely sacrifices the electrode capacity and limits the rate performance. In this work, we propose a strategy in which Li3VO4 is first broken into nanometer scale by high energy ball milling to increase active surface and shorten the Li+ diffusion distance, and then the particle surface is homogeneously coated with nanolayered carbon via a chemical vapor deposition (CVD) method for electronic conductivity enhancement. The obtained nanosized Li3VO4 is uniformly coated by ~ 5 nm carbon layers. Compared to untreated counterpart, the modified Li3VO4, attributed to the synergetic effects of nanosize and carbon coating, exhibits an increased first coulombic efficiency from 68.8% to 79.5%, a higher reversible capacity from 225 to 315 mAh g-1, and superior rate performance. Importantly, the carbon-coated nanosized Li3VO4 with only 5% conductive additive exhibits better performances than the microsized raw Li3VO4 with 10% conductive additive, showing important effects of particle size and electronic conductivity on the electrochemical properties of Li3VO4.
