Zwitterionic Osmolyte-Inspired Additives As Scavengers and Low Temperature Performance Enhancers for Lithium Ion Batteries

Zwitterionic lithium-silica sulfobetaine silane (Li-SiSB) is fabricated and used as an additive together with hydroxyl-terminated poly(dimethylsiloxane) (PDMS-HT) for use as low temperature additives in lithium ion batteries (LIB). The additives dissolved in 1 M LiPF6 (ethylene carbonate/dimethyl carbonate = 1:1). The electrolyte containing Li-SiSB and PDMS-HT shows higher ionic conductivity (1.54 x 10(-3 )Scm(-1) at -20 degrees C). Full cells show enhanced specific capacity at higher C-rates in the presents of additives due to anti-freezing and enhanced ionic conductivity. The also enhance early, stable and dense SEI which in turn leads to improved cycling stability. These results merit the use of both Li-SiSB and PDMS-HT as electrolyte additives for improved low temperature performance in lithium-ion batteries. (C) 2021 Elsevier B.V. All rights reserved.