Mesoporous Li₂FeSiO₄/C as Cathode Material for Lithium Ion Battery

摘要

Mesoporous Li2FeSiO4/C nanocomposite cathode material has been prepared by a sol-gel methodbased on P123. Effect of calcinations temperature and carbon content on the electrochemicalperformance was investigated. The structure and morphology of the mesoporous materials wereexamined by X-ray diffraction, scanning electron microscopy, transmission electron microscopy andN2 adsorption/desorption techniques. The results indicate that the uniform nanometer-sized Li2FeSiO4particles are embedded in irregular mesoporous amorphous carbon. The mesoporous Li2FeSiO4 with9.22% carbon coating exhibits the best electrochemical performance especial rate performance. It has a-1 high initial discharge capacity of 178.4 mAh g at 1/16 C and reversible discharge capacity of 100.8-1 mAh g at 5 C after 100 cycles. The enhanced electrochemical performance can be ascribed to itssmall size, large specific surface area, uniform carbon-decoration and mesoporous structure.