Abstract
The development of high-performance rechargeable batteries is critical for the future of energy storage, with lithium metal anodes offering a promising avenue due to their high theoretical capacity and low electrochemical potential. However, lithium dendrite formation compromises their safety and cyclability. While classical nucleation theory explains growth at the mesoscale, the atomic-scale mechanisms governing lithium nucleation remain less understood. This study employs periodic density functional theory (DFT) simulations to investigate the early-stage nucleation of lithium atoms on lithium metal Li(100), Li(110) and Li(111) surfaces. Following the determination of pristine surface energetics and preferred adsorption sites, the analysis is extended to the effect of surface defects, such as oxygen, nitrogen, and fluorine, which commonly arise from interactions with manufacturing atmospheres and battery electrolytes. The findings of this study reveal that defect chemistry significantly alters nucleation behaviour, with fluorine defects acting as persistent nucleation seed sites which could promote uniform growth under sufficient concentration on the surface. These insights provide a fundamental understanding of lithium nucleation at the atomic level and suggest strategies for surface and electrolyte engineering to mitigate dendrite formation, ultimately contributing to the design of safer and more efficient lithium metal batteries.