Mechanism and solutions of lithium dendrite growth in lithium metal batteries

Lithium metal has traditionally been regarded as an ideal anode material for high energy density batteries owing to its ultra-high theoretical specific capacity (3862 mA h g-1), extremely low redox potential and low density. Developing lithium metal electrodes is of great significance for developing solid-state batteries. However, the safety issues caused by lithium dendrite growth during the cycling process of lithium metal batteries seriously hinder their commercial applications. Numerous works on how to suppress lithium dendrite growth and construct safe lithium metal batteries have been reported. This review focuses on the internal environment of lithium metal batteries (LMBs) and mainly discusses five possible mechanisms for lithium dendrite growth and three important strategies to suppress lithium dendrites. The effects of factors such as electrolyte composition, current density, metal valence states, and electric fields on the formation of lithium dendrites are revealed. Significant considerations for lithium metal anode development including appropriate electrolyte components, electrode interfaces, SEIs, separators, electrode fabrication strategies, and practical device engineering, and suggestions for future development are proposed. This work will provide a reference for the rational design of lithium metal batteries. Inhibiting lithium dendrite is a big challenge for developing lithium metal batteries. The work reviews possible mechanisms of lithium dendrite growth, discuses effective strategies for inhibiting lithium dendrites and proposes future direction.