Lithium Bis(trimethylsilyl) Phosphate as an Electrolyte Additive to Improve the Low-Temperature Performance for LiNi0.8Co0.1Mn0.1O2/Graphite Cells

Abstract

Lithium Bis(trimethylsilyl) Phosphate (LiTMSP) was incorporated as an electrolyte additive in LiNi0.8Co0.1Mn0.1O2(NCM811)/graphite cells for improving the low-temperature performance. Previously, we reported the bi-functional roles of LiTMSP for LiNi0.5Mn1.5O4/graphite cells, which are hydrogen fluoride (HF) scavenger and film-forming agent. In this work, NCM811/graphite cells with LiTMSP (1 wt%) have better rate performance at -10 degrees C than cells without LiTMSP. This is due to the reduced resistance of NCM811/graphite cells with the addition of LiTMSP, resulting from LiTMSP induced-surface film generated on graphite electrodes which has improved lithium-ion conduction.