The invention discloses a low-temperature high-ionic-
conductivity ether-ester composite
sodium ion electrolyte and a preparation method thereof, and belongs to the technical field of
energy storage battery materials, the
electrolyte comprises
ethylene glycol
dimethyl ether,
ethylene carbonate and methyl
ethyl carbonate as basic solvents, and two brand-new modified compounds, namely methyl-2-(2, 2, 3, 3-tetrafluoropropoxy)-1, 2, 3, 4, 4-tetramethyl-1, 3, 4, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4-tetramethyl-1, 3, 4- According to the invention, 2, 3-
dioxolane-4-yl
phosphonate and cyclo (2-hydroxypropyl-2 '-hydroxyethyl)
sulfate are used as auxiliary materials, and fluoroethylene
carbonate,
sodium bis (fluorosulfonyl)
imide and
sodium perchlorate are used as auxiliary materials. Wherein the
freezing point of fluoroether
phosphonate is reduced through a fluorinated
chain segment, and a phosphonic
acid group promotes
ion dissociation and stabilizes an interfacial film; the cyclic hydroxyl
sulfonate inhibits molecular association through a cyclic structure, hydroxyl reduces the
viscosity of a
solvent, and
sulfonate groups optimize the
conductivity of an interfacial film. The prepared low-temperature high-ionic-
conductivity ether-ester composite sodium
ion electrolyte is high in
ionic conductivity at low temperature, stable in interfacial film and long in cycle life.