Mechanisms of Li ion transport in zwitterionic electrolytes from molecular dynamics simulations

Zwitterions possess both cationic and anionic groups covalently tethered within the same molecule, leading to unique properties. Recent studies have shown that polymer electrolytes with zwitterionic side chains exhibit remarkably high ionic conductivity and a high Li ion transference number, making them highly attractive for lithium-ion battery applications. However, the precise mechanisms that lead to these enhanced Li transport properties remain elusive. To provide deeper insight into the ion transport mechanism, we performed all-atom molecular dynamics simulations of amorphous zwitterion and Li salt mixtures. We explored the dynamic properties of the Li salts, the detailed local structures, and the interactions between Li ions and zwitterions/anions as a function of salt concentration. In this talk, we will discuss how these atomic-level interactions and structures correlate with the overall ion transport properties and offer strategies for tuning electrolyte performance.