锂离子电池负极材料MCMB的过充电行为

The overcharge behavior of MCMB anode material for Li-ion battery

研究了过充电对MCMB电极性能的影响。在电位为-0.045 V(vs.Li/Li+)时,会发生锂的沉积,且过充时间越长、倍率越高,锂的沉积质量越大。过充电后,MCMB电极的充放电性能下降。SEM与XRD的分析结果说明:过充电后MCMB电极的结构没有发生变化,性能下降是电极表面沉积的锂与电极表面形成的钝化膜所致。

The influence of overcharging on the performance of MCMB electrode was investigated. Lithium would deposit at the potential of - 0.045 V （ vs. Li/Li^＋ ）, the lithium deposition quantity was increased with the increasing of overcharge time and rate. The charge-discharge performance of MCMB electrode was decreased after overcharge. The results of SEM and XRD analyses showed that the structure of MCMB electrode did not change after overcharge, the decrease of performance was caused by the thicker passivation film forming by the reaction of electrolyte and lithium depositing on the surface of electrode.