Multifunctional organosilicon compound contributes to stable operation of high-voltage lithium metal batteries

With the increasing demand for high-energy–density energy storage devices, lithium metal batteries have rekindled the interest of researchers due to ultra-high specific capacity. However, the extremely unstable interfaces between the electrolyte and electrodes limit its application seriously. Herein, we introduce an organosilicon compound, 1,3-Divinyltetramethyldisiloxane (DTMDS), as multifunctional electrolyte additive to enhance the performance of LiNi0.5Mn1.5O4/Li batteries. DTMDS contains two functional groups: siloxane groups (Si-O) and unsaturated carbon-carbon double bonds (CC). Siloxane groups can capture hydrogen fluoride (HF) in electrolyte, and the carbon-carbon double bonds can form thin and dense passivation layer on both cathode and anode surfaces by polymerization. As a result, the capacity retention of the batteries can retain more than 95% after 500 cycles. This work provides a valuable reference for the design of multifunctional additives and stabilizing the interfaces of high-voltage lithium metal batteries.