(Invited) A Chemical Mechanism of Carbonate Electrolyte Failure at Silicon Anode Interface for New Electrolyte Design

Abstract

Silicon (Si) anode has tremendous potential for the next-generation high energy density lithium-ion battery, but the development of devices with sufficient capacity retention and calendar life remains elusive. While numerous studies have characterized the composition and dynamics of the solid-electrolyte-interface (SEI) on silicon anodes, the chemical mechanisms that produce the identified species remain largely speculative and conflicting. In this presentation, we demonstrate the use of trimethylsilyllithium as a model compound to study the chemical mechanisms of electrolyte failure unique to silicon anodes. The insights from this mechanistic study led to the rational design of new electrolytes that outperform traditional EC-based carbonate electrolytes demonstrated in NMC811/Si full cells.