Review on dendrite formation of Mg metal anode and its prevention

Rechargeable batteries with metal anodes are recognized as a good option to respond to contentious demand for increasing energy density. However, dendric metal deposition is uncontrollable and causes low Coulomb efficiency and short-circuiting, leading to serious safety issues. Dendric deposition is observed very often in Li and Na metals, while dendrite-free deposition with 100 % Coulomb efficiency is achieved in Mg metal. Additionally, high natural abundance, good machinability, and high stability in ambient conditions of Mg metal make Mg metal anode an ideal metal anode. In 2017, dendric deposition of Mg metal is discovered and possible dendric Mg deposition is also proved by the simulation. These studies reclaim a new research area in developing rechargeable Mg batteries. Recently, the mechanism and suppression of dendric Mg deposition have been studied intensively. In this mini-review, the dendric deposition of Mg metal and its prevention are reviewed. The features of Mg dendrite are studied compared to those of Li and Na dendrites. After that, research on preventing and suppressing Mg dendrite formation is analyzed and summarized. Finally, perspectives and challenges of Mg metal anode are proposed. [Display omitted] •A review article for dendric deposition of Mg metal anode for rechargeable magnesium batteries.•Mechanism of Mg dendrite formation and features of Mg dendrite are summarized.•Studies on the suppression of Mg dendrite are reviewed.•Perspectives and challenges of Mg metal anode are proposed.