LiAl LDH/细菌纤维素复合隔膜及其锂离子电池性能

LiAl LDH bacterial cellulose composite separator and lithium ion battery performance

隔膜作为锂离子电池主要部件之一,起到传输锂离子、防止正负极接触短路的作用,是保护电池安全的重要屏障。通过水热法合成了LiAl LDH无机颗粒,与细菌纤维素复合后,通过真空辅助抽滤的方法,制备了一种耐热性好、电解液浸润性高及对锂枝晶具有抑制作用的功能化复合隔膜。LiAl LDH无机粉末颗粒的加入,使复合隔膜具有高的离子电导率(1.29 mS/cm)、高的吸液率(257%)。200次循环稳定性测试后,依然有着较高的容量保持率(98.8%)。界面稳定性测试中,复合隔膜对锂枝晶的抑制作用优于聚烯烃隔膜。为发展高安全性锂离子电池隔膜提供了一种可行的方法。

The separator is a crucial component that prevents the direct contact of anodes and cathodes and facilitates lithium ions to shuttle between the two electrodes.Moreover,the separator plays a vital role in ensuring the safety of batteries.In this paper,LiAl LDH inorganic particles were synthesized by hydrothermal reaction,and blended with bacterial cellulose dispersion.The functional battery separator,prepared by vacuum assisted filtration,has excellent heat tolerance,high electrolyte wettability and inhibition on lithium dendrites.Meanwhile,high ionic conductivity(1.29 mS/cm)and high electrolyte uptake(257%)are exhibited.After 200 cycle stability test,the battery still has a high capacity retention rate(98.8%).In the interface stability test,the composite separator has better inhibition effect on lithium dendrites than polyolefin counterpart.This provides a feasible method for the development of high safety lithium ion battery separators.