Choline Chloride-Urea Deep Eutectic Solvent As Promising Electrolyte for Zinc Ion Batteries

Zinc-ion batteries (ZIBs) have received increasing attention due to their safety, environmental friendliness, cost-effectiveness. Though aqueous-based ZIBs show great promise, their critical challenges involve zinc anode corrosion and passivation, and dendritic zinc formation during recharge. We reported the application of biocompatible, nonaqueous, and low-cost electrolyte based on choline chloride/urea deep eutectic solvent for rechargeable ZIBs (δ-MnO 2 intercalation cathode). The behavior of zinc anode stripping and deposition in the electrolyte, as well as intercalation into the δ-MnO 2 cathode, were investigated. The results revealed that the fabricated battery exhibited good electrochemical performance with the maximum specific capacity of 170 mAh/g. Besides, the system showed reversible plating/stripping of zinc without dendrite formation and zinc anode passivation. Hence, the results confirmed the reversible intercalation of zinc into the δ-MnO 2 cathode. The proposed electrolyte shows good promise for Zn/δ-MnO 2 battery system. Figure 1