DMSO-assisted liquid-phase synthesis of LiFePO4/C nanocomposites with high-rate cycling as cathode materials for lithium ion batteries

摘要

Nanometer-sized LiFePO4 was synthesized by a liquid-phase method, using dimethyl sulfoxide (DMSO) as a boiling point raiser and crystal growth inhibitor under ambient pressure, then mixed with a certain amount of glucose and sintered at 600 C under inert atmosphere for 3 h to obtain LiFePO4/C nanocomposites, which had a well developed olivine-type structure, small crystals, and a narrow size distribution. Tests showed that the special capacity of LiFePO4/C at discharge rates of 0.2 and 1 C was 157.7 and 142.5 mAh/g, respectively. A capacity of 126 mAh/g at 5 C and 104 mAh/g at 10 C was even achievable, with no significant capacity fading after 200 cycles.