Emergence of nonaqueous electrolytes for rechargeable zinc batteries

In the quest for safer and cheaper batteries, rechargeable batteries based on zinc demonstrate great potential in many energy storage applications. Zinc is cheap, safe and abundant. Despite this, the commercialisation of rechargeable zinc batteries, particularly based on aqueous electrolytes, remains significantly challenging, mainly due dendritic growth and passivation of zinc which inhibits its long-term cycle stability. Herein, we provide a comprehensive review on some of the recently emerging nonaqueous electrolytes, including organic solvents, superconcentrated salts, deep eutectic mixtures and ionic liquids, which offer many advantages over aqueous systems. We also discuss some of the challenges that need to be addressed to establish rechargeable zinc batteries as a mainstream option.