Tracing the Staging Dynamics and Li+ Kinetics in Graphite Anodes via Automated Continuous (De)Lithiation Simulation

Abstract

Revealing dynamical structural evolution during cycling is crucial for stable, fast-charging graphite anodes in lithium-ion batteries. However, coupling mechanisms among carbon-layer behaviors, (de)lithiation/diffusion, and defect regulation remain insufficiently understood. Here, we developed an automated workflow to enable molecular dynamics resolution of continuous structural and atomic-layer evolution. By constructing stacking fault models, we successfully simulated stage structure transitions driven by carbon-layer sliding and reorganization. During cycling, carbon-layer dynamics modulate (de)lithiation positional selectivity, which facilitates staging-structure formations/transitions. A fundamental kinetic asymmetry arises during cycling, driven by continuous and heterogeneous lithium transport and carbon-layer sliding. Defects regulate atomic-layer movement, in which atomic-scale defects confine intralayer lithium transport and carbon-layer sliding while enabling lithium interlayer transport via dynamic trapping/release mechanisms, and atomic-layer-scale defects concurrently boost lithium diffusivity and ameliorate stress distributions. For future graphite anode design, we should utilize controllable carbon-layer behaviors and tunable defects to enhance lithium transport, mitigate structural evolution asymmetry, and maintain mechanical stability.