Re-envisioning the Key Factors of Magnesium Metal Anodes for Rechargeable Magnesium Batteries

The growing interest in rechargeable magnesium batteries (RMBs) stems from the demands for energy storage technologies with safety, sustainability, and high energy density. However, the ambiguous mechanism of the Mg metal anode during the electrochemical and manufacturing processes severely impedes the pursuit of superior performance. Those commonly overlooked bottlenecks in pure Mg or Mg alloy metal anodes should be emphasized and deserve more consideration. In this Review, a brand-new perspective is emerging to reveal the opportunity for overcoming the long-standing obstacles hindering the development of RMBs. Herein, we comprehensively discuss the recent efforts to relieve the interfacial incompatibility between Mg metal anodes and electrolytes, including the pursuit of new electrolyte, interfacial modification, mechanism exploration, etc. Additionally, we put forth an unconventional research direction to promote the development of RMBs, namely exploring Mg metal anodes in terms of their electrochemical and mechanical properties. In closing, our proposals for addressing the key factors and intractable issues with Mg metal anode are brought forward.