The invention discloses a combined negative
electrode additive for a
zinc-
bromine flow battery, a negative
electrode electrolyte, a preparation method of the negative
electrode electrolyte and the
zinc-
bromine flow battery, and belongs to the technical field of
electrochemical energy storage, and the combined negative electrode additive for the
zinc-
bromine flow battery comprises
indium trichloride and
glycine in a
molar ratio of 1: (3.33-60); during charging,
indium ions in
indium trichloride are reduced into
metal indium on the surface of the electrode, the
metal indium and the post-deposited zinc generate a nanoscale
alloy layer in situ,
electric field distribution is homogenized, and zinc dendritic
crystal growth is inhibited; carboxyl and amino of
glycine are used as
electron donors to form a water-soluble complex with zinc ions, so that the reduction
kinetics of the zinc ions on the surface of the electrode is slowed down; polar functional groups of
glycine are adsorbed on active sites on the surface of a zinc electrode,
zinc ion deposition is blocked,
energy distribution of the electrode and an
electrolyte interface is changed, zinc is guided to perform transverse two-dimensional growth, zinc
dendrite growth is inhibited, hydroxyl ions are neutralized, and
hydrogen evolution reaction is inhibited. The coulombic efficiency of the zinc-bromine flow battery is 95.4%-97.0%; the energy efficiency ranges from 81.85% to 84.49%; and the
voltage efficiency is 85.8%-87.1%.