The invention provides a preparation method and application of an aqueous
composite electrolyte. The preparation method comprises the following steps: uniformly mixing aqueous
zinc salt and a water-soluble
heterocyclic amine organic additive; and adding deionized water, continuously stirring until the solution is dissolved, and standing until the pH value is stable to obtain the aqueous
composite electrolyte. The additive can improve the stability of the
aqueous electrolyte, and
zinc-philic groups in molecules of the organic additive can form coordinate bonds with
zinc ions, so that the molecules of the additive can be adsorbed on the surface of a zinc
electrode,
electric field distribution on the surface of the
electrode is balanced, non-uniform deposition of the zinc ions on the surface of the
electrode is prevented, and the stability of the
aqueous electrolyte is improved. Dendritic
crystal growth caused by too strong local
electric field is reduced, meanwhile, the
utilization rate of zinc is increased, and the performance of the battery is effectively improved; after the additive molecules are adsorbed on the surface of the zinc electrode, a part of active sites for analyzing
hydrogen reaction on the surface of the electrode can be covered, the
hydrogen evolution reaction is inhibited, the generation of byproducts is reduced, the coulombic efficiency is improved, and the
corrosion resistance and the
cycling stability of the zinc negative electrode are effectively improved.