Electrolyte\nDesign for Silicon-Based Li-Ion Battery\nGuided by Chemical Reactivity of Solvents with a Model Silicon Anode

The use of a model compound trimethylsilyllithium\nwas demonstrated\nto study the chemical reactions of electrolyte with as a principal\nguide to design electrolyte for silicon-based Li-ion battery. Me<sub>3</sub>Si<sup>–</sup> anion initiates ring-opening polymerization\nof EC leading to the formation of poly(ethylene ether carbonate),\nwhich subsequently defragments into oligomers and dissolves in electrolyte.\nFEC was found to react differently, generating LiF and vinylene carbonate\n(VC). Further reaction of VC with Me<sub>3</sub>SiLi generated poly(hydroxymethylene),\nwhich is a nonsoluble polymer and the critical SEI component. The\ninsights from this study have guided the new electrolyte design for\nthe Si-based battery.