Modeling the effects of pulse plating on dendrite growth in lithium metal batteries

The formation of dendrites on lithium electrodes presents safety and cycling challenges for the development of high-performance, rechargeable lithium metal batteries. While a constant current (CC) charging protocol has been standard, recent studies have shown that a pulse plating (PP) charging protocol is effective at reducing dendrite growth and improving cycle life. In this study, dendrite growth at the anode-electrolyte interface was simulated using an Extended Butler-Volmer Smoothed Particle Hydrodynamics (eBV-SPH) model implemented in LAMMPS. Square waveform PP protocols were implemented and compared to CC results to understand the effect of charging protocols on lithium deposition and dendrite morphology. The charging conditions were controlled by the applied potential, as the model does not currently enforce galvanostatic conditions. Past studies compared CC and PP results at a single charging current density. In similar work on lithium-ion batteries, PP and CC results compared at the identical mean current resulted in little to no benefit to cycling performance. In this investigation, lithium anode PP protocols performed worse when compared with CC plating at the identical mean current. The PP and CC simulation results from the eBV-SPH model simulated the expected morphology and behavior found in experimental investigations and provide more detailed morphologies than previous computational simulations.