  Lithium metal batteries are seen as a critical piece towards electrifying
aviation. During charging, plating of lithium metal, a critical failure
mechanism, has been studied and mitigation strategies have been proposed. For
electric aircraft, high discharge power requirements necessitate stripping of
lithium metal in an uniform way and recent studies have identified the
evolution of surface voids and pits as a potential failure mechanism. In this
work, using density functional theory calculations and thermodynamic analysis,
we investigate the discharge process on lithium metal surfaces. In particular,
we calculate the tendency for vacancy congregation on lithium metal surfaces,
which constitutes the first step in the formation of voids and pits. We find
that among the low Miller index surfaces, the (111) surface is the least likely
to exhibit pitting issues. Our analysis suggests that faceting control during
electrodeposition could be a key pathway towards simultaneously enabling both
fast charge and fast discharge.
