Dendrite-free Lithium Based on Lessons Learned from Lithium and Magnesium Electrodeposition Morphology Simulations

Abstract

Electroplating is one of the most common processes to create smooth surfaces and thin coatings, but achieving smooth lithium (Li) plating without Li dendrite growth remains a challenge for developing next-generation Li-ion batteries based on Li metal anodes. One of the main reasons is our inability to directly model and predict the atomistic and mesoscale mechanisms underlying the complex electroplating process involving concurrent ionic transport, redox reactions, and development of morphological instability. Here we report a multiscale model integrating atomistic calculations of charge transfer physics with the mesoscale phase-field model to understand and predict morphological evolution for general metal electrodeposition processes. The results reveal that the difference in cation desolvation-induced exchange current is mainly responsible for the dramatically different dendritic Li plating and smooth magnesium (Mg) plating. This study provides a strategy for designing dendrite-free Li-ion battery anodes guided by a multiscale model integrating the phase-field method and atomistic calculations.