The invention discloses a two-phase
electrolyte, a preparation method thereof and a liquid
energy storage battery system, and belongs to the technical field of
electrochemical energy storage. According to the invention, a liquid-liquid double-phase
electrolyte is composed of a water-phase
electrolyte and an organic-phase electrolyte, wherein the organic-phase electrolyte contains a
coupling system of 1-(methyl-decyl)-3-methylimidazolium
bromide,
tris (methyl-decyl) methyl
ammonium bromide and (10-octadecyl)
alkyl trimethyl
ammonium bromide in a
molar ratio of (5-7): (2-4): 1. During charging, positive
electrode bromide ions are subjected to an oxidation reaction to generate a
bromine simple substance, and meanwhile, the
bromine simple substance and a
coupling system of the
quaternary ammonium bromide compound and the
bromine complexing agent provided by the invention form a stable polybromine complex product, so that the polybromine complex product is prevented from being migrated into a water-phase electrolyte, and the purpose of improving the stability of the water-phase electrolyte in the absence of a diaphragm is achieved. The self-
discharge reaction of bromine is significantly inhibited at a high temperature exceeding the
boiling point temperature of bromine, the coulombic efficiency and energy efficiency of the liquid
energy storage battery are improved, the
system cost is reduced, and the long-term cycle stability of the liquid
energy storage battery is improved.