锂离子电池正极材料LiCoO_2抗过充性能

The overcharge-resistant ability of layered-LiCoO_2 as cathode materials for rechargeable lithium batteries

对钴酸锂在过充循环后的结构进行了研究。容量和循环的结果表明 :在高电压范围内 (4 .7V～ 3 .3V) ,前几次循环的容量会迅速衰减 ,但很快就会稳定在一个数值。当再把电压范围降到 4.3 5V～ 3 .3V循环时 ,电池的容量会保持在110mAh/ g以上 ,其充放电效率保持在 99%以上。XRD结果表明经过在高压范围内的多次充放电循环后 ,材料的结构没有完全被破坏 ,但也不会是单一的六方相 ,而可能是一种两相共存体。

The electrochemical properties of LiCoO 2 for cathode materials of Li ion battery were investigated by constant current charge discharge experiments and cyclic voltammetry. The result showed that after cycling under high voltage (4.7V), the microstructure of layered LiCoO 2 might not be completely destroyed. Based on the experimental results,two phases: hexagonal and spinel like phases coexisting in the host structure were proposed