Modeling lithium-ion solid-state electrolytes with a pinball model

Abstract

New solid-state lithium-ionic conductors can lead to significant improvements in the safety and performance of Li-ion batteries, but current modeling approaches based on first-principles methods can be exceedingly expensive for screening purposes. By applying some simple, physically motivated approximations to density functional theory, the authors obtain a hybrid quantum-mechanical/classical model that can tackle the time and scale limitations of full first-principles methods while retaining the accuracy needed to model reliably the dynamics of lithium ions in common solid-state host structures. They show this for different known ionic conductors, while also clarifying the role of host-lattice vibrations for Li-ionic transport in some test cases.