Sunday, 9 October 2022: 08:40
Galleria 4 (The Hilton Atlanta)
Silicon owing to its abundance, low working potential and high theoretical specific capacity has been regarded as one of the promising anode materials for the next generation lithium-ion batteries (LIBs). The bottleneck of Si anode practical application is its large volume variation and formation of reactive silicide species at the anode/electrolyte interface during lithiation which result in continuous SEI formation and consumption of active electrolyte components. The new electrolyte design strategies have shown to stabilize the Si electrode via an in situ electrochemical formation of a metastable ternary Li-Mg-Si phase. In this study, the effect of electrolyte modification on the dynamic formation of solid electrolyte interphase (SEI) on Si anode is investigate in the pre-lithiation versus post-lithiation stages of electrochemical cycling. In addition, combined EQCM-EIS are used to investigate the charge transfer mechanism and the resistivity of the surface film at various stages of cycling. The understanding of the stabilization effect of Mg salt on Si surface chemistry may have a great impact on the development of Si-based anodes for lithium-ion batteries.