Simulating lithium deposition on planar anode: The role of particle reservoir and the influence of dendrite growth on current density profiles

Abstract

In this work, we developed a computational model of lithium deposition on planar electrodes. With this model, we simulated several chronoamperometry experiments considering different deposition probabilities, i.e. cell overpotentials. Since the planar geometry induces an ion concentration gradient profile that continues to evolve toward the bulk electrolyte, we studied the influence of the lithium reservoir and rationalized its role in the real system. The solid electrolyte interface (SEI) is conceptualized as a thin layer whose thickness determines the ion diffusion profile. Additionally, the impact of dendrite formations on electrode roughness and current density profiles was analyzed by comparison with test simulations assuming inhibited dendrite growth. By presenting current density profiles in quantitatively meaningful units, our work narrows the gap for further comparison with experimental measurements. The util- ity of our simulations for determining the electrode area in lithium metal batteries is addressed.