Electrolyte Composition Effects on the Formation of the Solid Electrolyte Interphases of Li-Metal Batteries: A Molecular Dynamics Study

We will present our recent effort to develop new materials for batteries using our nanobattery model able to simulate a much smaller battery containing all the main components of an actual size battery. We are testing Li-metal anodes with sulfur- and metal-oxide-based cathodes together with highly concentrated electrolytes as well as with localized highly concentrated electrolytes. Our approach consists on performing ab initio analysis and ab initio molecular dynamics simulations in order to determine energetics properties as well as reactive force fields to perform larger scale reactive molecular dynamics simulations that eventually will allow us to evaluate prospective battery systems based on cycling stability, formation of benign solid-electrolyte interphases, interfacial stability, ion-transport and its mechanisms, electron-transfer, output voltage, current and charge thresholds, battery capacity, ion-pairing, cluster and death lithium formation, dendrite growth, capacity fading. In the present work, we use molecular dynamics simulations to model a TMP-based electrolyte comprising TMP, lithium, and bis(fluorosulfonyl)imide (LiFSI) salt, exploring the effects of salt concentration on solvation and ion transport. A statistical analysis is performed to study ion pairing, clustering, mobility, and coordination of Li-ion with and without small amounts of diluent materials.