MCMB粒度及分布对锂离子蓄电池性能的影响

Effect of MCMB particle and its distribution on the performance of Li ion battery

中间相碳球微珠（ＭＣＭＢ）是一种常用的锂离子蓄电池负极材料。文中就其粒度及其分布对电池性能的影响加以研究讨论。将ＭＣＭＢ按粒度与分布分成五组，按相同工艺制成ＩＣＲ１８６５０ 电池，测试电池初容量效率和循环寿命，结果表明：粒度及分布由小到大，初放效率由８６％ 升高到９１％ ；合理的粒度分布有利于提高电池的循环寿命，颗粒度Ｄ５０ 在２０ μｍ ，且分布呈偏心正态分布。

MCMB is widely used as anode material in Li ion battery. The effect of MCMB particle size and its distribution on battery performance was discussed. ICR 18650 lithium ion batteries were made by using five MCMB samples with different particle size and distributions, and their coulombic efficiency and cycle life were tested. The results show that initial coulombic efficiency increased from 86% to 91% when par ticle sizes and distributions change from small to big and the proper particle and distribution can improve cycle life. The battery provides higher capacity and longer cycle life when the particle size D 50 is near 20 μm and is in eccentric normal distribution.