The invention discloses a
zinc ion battery electrolyte as well as a preparation method and application thereof, and belongs to the technical field of aqueous
zinc ion batteries. The
electrolyte comprises deionized water, soluble
zinc salt and an
ionic liquid additive, preferably, the
ionic liquid is 1-ethyl-3-methylimidazole
ethyl sulfate salt, and the adding concentration is 0.02-0.5 mol / L <-1 >. The additive can be preferentially adsorbed on the surface of the zinc negative
electrode to form a protective layer, contact between
free water and the zinc negative
electrode is effectively blocked, and
hydrogen evolution reaction and by-product generation are remarkably inhibited; meanwhile, zinc ions are guided to be uniformly deposited along a flat
crystal face, and dendritic
crystal growth is inhibited. The cycle life of the zinc symmetric battery assembled by adopting the
electrolyte is prolonged by about 18 times, the coulombic efficiency of the zinc-
copper asymmetric battery reaches 99.8%, and the capacity
retention ratio is improved to 84% after the whole battery is circulated for 1000 times. The method is simple in process, low in cost, environment-friendly and suitable for large-scale
energy storage application.