Onset of Lithium Plating in Fast-Charging Li-Ion Batteries

Lithium (Li) plating is a major challenge limiting the adoption of fast-charging Li-ion batteries, yet its onset mechanisms remain elusive. We present a model of Li plating on a graphite particle coated with a solid electrolyte interphase (SEI) layer to elucidate the coupled effects of ion transport, reaction kinetics, and phase transformation. We derive an analytical expression that relates Li-plating onset time to operating conditions and material properties and introduce a Li-plating diagram. Our framework captures the intricate mechanisms driving Li plating and anode potential drops, extending beyond existing limiting cases of surface ion saturation and electrolyte depletion. By providing an improved understanding of the interrelationships among key parameters, our findings provide valuable guidance for adjusting charging protocols, designing cell components, and engineering artificial SEI layers. Implementing these strategies can help mitigate Li plating and ensure Li-ion battery safety and performance during fast charging.