Accelerating Zn2+ kinetics and regulating zinc anode interface for high stable aqueous zinc-ion batteries

Aqueous zinc-ion batteries are promising for large-scale energy storage. However, their practicability and industrialization still face challenges due to the issues such as hydrogen evolution, corrosion, and zinc dendrites, which seriously limit their cycling life. This study introduces a cost-effective and practical solution to enhance the reversibility and cycle life of Zn anodes. It is found that 1, 4-cyclohexanedione can regulate hydrogen bonds to reduce H2O activity and accelerate Zn2+ kinetics. This organic molecule with symmetric carbonyl group and steric hindrance effect from the six-membered ring can mitigate the tip effect to inhibit the zinc dendrite formation. The Zn|| NH4V4O10 cell exhibit a capacity of 135.6 mAh g-1 and 75% capacity retention after 1400 cycles at 4 A g-1. This work demonstrates the significant potential of this multifunctional and low-cost additive to extend the cycle life of the batteries, marking a step forward in their applicability for large-scale energy storage.