Undesired Reactions in Aqueous Rechargeable Zinc Ion Batteries

Rechargeable zinc-ion batteries (RZIBs) utilizing aqueous electrolytes can offer high safety, low cost, and fast charge/discharge ratings for large-scale energy storage. The use of water as electrolyte solvent facilitates low cost, facile processing, reduced safety concerns, and fast ion kinetics. However, free water molecules also instigate many simultaneously occurring undesired reactions in the RZIB system, leading to capacity fade and limited operational lifetime. Here, our review traces each undesired reaction and its cascade of detrimental ramifications on RZIB cycling. We discuss balancing merits, reported strategies, and future perspectives to mitigate these undesired reactions and further improve the RZIBs' operational lifetimes.