Lithium Electroreduction at Metal/Polymer Interfaces for Lithium Metal Batteries via Atomistic Molecular Dynamics Simulation

Understanding and stabilizing lithium electrodeposition is a major bottleneck for developing safe and cyclable lithium metal batteries. The process is complicated by the heterogeneous composition and structure of the solid electrolyte interphase (SEI). To establish a molecular understanding of lithium electroreduction, we employ atomistic molecular dynamics simulations to address ion solvation properties and electron-transfer kinetics of electrochemical reactions at a model SEI/metal interface. Our SEI model is a chemically and structurally well-defined homopolymer including poly (ethylene oxide) (PEO) and poly (ethylene carbonate) (PEC). Model electrodes are either pristine or structurally inhomogeneous with pre-existing deposits. Both the electrodes and deposited lithium are modeled using time-dependent induced-charge polarizability. In this talk, we discuss the effects of the SEI and surface-roughness on the kinetics and mechanism of interfacial lithium electroreduction.