From anode to cell: synergistic protection strategies and perspectives for stabilized Zn metal in mild aqueous electrolytes

Zn metal anode inevitably suffers from the dendrite growth, hydrogen evolution reaction, and surface passivation in aqueous zinc ion batteries (AZIBs), which have significantly compromised the electrochemical behavior of electrodes and hampered AZIBs from being further employed in energy storage system (ESS). Very recently, remarkable efforts have been made to resolve the above-mentioned issues via artificial interface engineering, electrodes structure and constitution design, electrolyte optimization, and novel separators. However, the optimization of anodes alone does not necessarily match the cathode, and excessive anode protection will exert opposite effects on electrochemical performances of full cells. In this paper, the central tenet is to provide a comprehensive and insightful analysis of these anodic protection strategies, focusing on the compatibility of these strategies with cathodes and the promotion of full cells. Furthermore, synergetic protection strategies are presented as the most promising option for the next generation Zn metal anode. Moreover, the perspectives of Zn metal anode are discussed to facilitate the exploration of AZIBs. This paper is expected to provide new insights for the rational design of next generation advanced anodes in AZIBs.