Lithium Bis(trimethylsilyl) Phosphate as an Electrolyte Additive to Improve the Low-Temperature Performance for LiNi_0.8Co_0.1Mn_0.1O₂/Graphite Cells

Lithium Bis(trimethylsilyl) Phosphate (LiTMSP) was incorporated as an electrolyte additive in LiNi_0.8Co_0.1Mn_0.1O₂(NCM811)/graphite cells for improving the low-temperature performance. Previously, we reported the bi-functional roles of LiTMSP for LiNi_0.5Mn_1.5O₄/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 °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.