Enhanced Electrochemical Performance of Zinc Batteries with a Nonaqueous Eutectic Electrolyte

Rechargeable zinc-based batteries have garnered significant interest due to their high safety, low-cost, and promising energy storage potential. However, challenges such as dendrite formation, low reversibility of Zn anodes, intrinsic hydrogen evolution reactions, and the limited stability of cathode materials in aqueous electrolytes continue to hinder their widespread commercialization and long-term performance. Herein, we report a nonaqueous eutectic electrolyte composed of triethylamine hydrochloride and zinc trifluoromethanesulfonate for the application of Zn batteries. The electrolyte enables highly reversible plating/stripping with a 2.2 V oxidative stability window (vs. Zn²⁺/Zn), stable cyclability for >6000 hours, and a wide liquid range (T_liquid>-50 ^oC). Zn dendrite morphology was studied via operando optical spectroscopy, showing uniform deposition at 1 mA/cm² under galvanostatic conditions. Vanadium oxide (V₂O₅) as a cathode for Zn batteries demonstrates a capacity of 120 mAh/g, retaining 67% of its capacity after 1000 cycles. The electrolyte presents a promising alternative to conventional aqueous electrolytes, offering enhanced stability, and performance for future energy storage applications.