Effects of Optimized Electrode Surface Roughness and Solid Electrolyte Interphase on Lithium Dendrite Growth

Lithium metal is an ideal anode material for high‐energy‐density rechargeable batteries. However, harmful dendrites lead to short circuit and cause safety hazards. Herein, a fundamental study on increasing the roughness of the electrode and its influence on the behaviors of lithium dendrites by combining experiment and simulation is presented. Various aspects of the growth behaviors of lithium dendrite on the electrode surface are investigated with consideration of the overpotential, roughness, and the solid electrolyte interphase (SEI). In situ observation of experimental results show that the electrode surface becomes rough gradually during the charging process, and the rough electrode surface promotes the formation of disordered dendrites. The simulation results also show that it is easy to form dendrites on the surface of electrodes with higher roughness. Higher overpotential leads to uneven deposition of reduced lithium and promotes the formation of lithium dendrites. A thicker SEI and lower conductivity can effectively slow down the growth of dendrites. Herein, the overpotential, protuberance, and SEI are preliminarily designed to suppress the growth of dendrites effectively. These results supply useful information for the optimal design of electrode surface patterns and an artificial SEI.