(Invited) Microstructural Modeling of Heterogeneous Nucleation and Growth of Lithium Electrodeposits

Through numerical modeling and simulation, we explore the charge/discharge conditions that lead to the formation of lithium dendrites in rechargeable lithium-ion batteries. Firstly, by using high resolution X-ray tomography, a three-dimensional representation of a lithiated graphite anode microstructure from a commercial battery was used as input to simulate the local electrochemical behavior that will favor heterogeneous lithium nucleation. The analysis demonstrates that spatial variation in porosity, particle roughness and morphology significantly alter the local intercalation kinetics, state of charge and mechanical stability, and dendrite formation. Secondly, by using the phase field approach, we demonstrate the conditions that will enable an overpotential-controlled critical lithium electrodeposit to become energetically favorable and identify the regimes of dendrite nucleation, growth, and suppresion behavior.