Abstract:Magnesium ion batteries have been widely studied in recent years due to their advantages of abundant raw materials, low cost, environmental friendliness and high volumetric specific capacity. However, its development and practical application are limited by the slow diffusion kinetics of Mg2+, the formation of passivation layer on the surface of magnesium metal anode during cycling, and the sensitivity of electrolyte to air, strong corrosion and low voltage window. It is very important to explore suitable electrode materials and electrolytes with good compatibility. Herein, the working principle of magnesium ion batteries is described briefly. The research status of cathode and anode materials as well as electrolytes are summarized, and the existing problems and corresponding solutions are discussed elaborately in order to promote the further development of magnesium ion batteries.