A Perspective: the Technical Barriers of Zn Metal Batteries

Energy storage will witness a leap of understanding of new battery chemistries. Considering the safety that cannot be compromised, new aqueous batteries may surface as the solutions to meet the immense market needs, where the growth of renewables is no longer limited by the lack of storage. Aqueous Zn-metal batteries are intriguing candidates to deliver the desirable properties and exhibit competitive levelized energy cost. However, the fact that most commercial Zn batteries are primary batteries states the difficulty of reversibility for the reactions of electrodes in such batteries. This article will highlight the practical needs that guide the development of storage batteries. The causes of irreversibility for both cathode and zinc metal anode are discussed, and the potential solutions for these challenges are summarized. Zn metal batteries may one day address the storage needs, and there exists a vast potential to further improve the properties of reactions in this battery.