Nitroso grafted carbonate electrolyte of lithium battery and preparation method

Abstract

The invention discloses a nitroso grafted carbonate electrolyte of a lithium battery and a preparation method. By performing mixed treatment on ethylene carbonate and propylene carbonate through nitrite, adding a small amount of fluoroethers and borate as auxiliaries simultaneously, heating at a low temperature (40-50 DEG C) in a water bath and rapidly stirring, and adjusting pH to be weakly alkaline simultaneously, NO2- obtained after nitrite ions are decomposed is additionally reacted with alkyl alkenyl and carbonyl groups of the ethylene carbonate and the propylene carbonate, the antioxidant properties of carbonate are improved by the combined action of the fluoroethers and nitroso groups, meanwhile, the grafting of small molecular groups can reduce the overall viscosity of a liquid, and a part of nitrogen atoms enter a carbon chain in a substitutional manner to cause structural defects and reduce the combined energy of the nitroso groups.

Description

technical field [0001] The invention relates to the field of lithium batteries, in particular to lithium battery electrolytes, in particular to a lithium battery nitroso-grafted carbonate electrolyte and a preparation method. Background technique [0002] Lithium battery electrolyte is the carrier of ion transport in the battery. Generally composed of lithium salt and organic solvent. The electrolyte plays the role of conducting ions between the positive and negative electrodes of the lithium battery, which is the guarantee for the high voltage and high specific energy of the lithium ion battery. The electrolyte is generally prepared from high-purity organic solvents, electrolyte lithium salts, necessary additives and other raw materials under certain conditions and in a certain proportion. The main components of lithium battery solution generally include the following seven types: 1. Ethylene carbonate, propylene carbonate, diethyl carbonate, dimethyl carbonate (dimethyl ...

AI Technical Summary

Problems solved by technology

The preparation method of the electrolyte is as follows: add metal lithium or Li2S and elemental sulfur into an organic solvent in a molar ratio, react at room temperature and under the protection of an inert atmosphere to obtain an electrolyte, and lithium salt can be selectively added to the electrolyte , shuttle inhibitors, etc.; also discloses a Li-S battery comprising the aforementioned electrolyte, its negative electrode active material is metal lithium or a lithium-containing alloy; its positive electrode active material is sulfur simple substance, organic sulfide, carbon-sulfur polymer At least one, and the positive electrode active material, conductive agent and binder form the positive electrode according to a certain mass ratio; wherein each mg of sulfur corresponds to an electrolyte consumption of about 0.04mL; the above-mentioned organic solvent is ethanol, acetonitrile, cyclohexane, Cyclohexanone, Isopropanol, Tetrahydrofuran, 2-Methyltetrahydrofuran, Ethylene Carbonate, Propylene Carbonate, Butylene Carbonate, Dimethyl Carbonate, Diethyl Carbonate, Methyl Ethyl Carbonate, Methyl Propyl Carbonate, Formic Acid Methyl ester, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, dimethoxyethane, 1,3-dioxolane, At least one of ethylene glycol dimethyl ether, diglyme, tetraglyme, diethylene glycol dimethyl ether, sulfolane, dimethyl sulfoxide, and dimethyl sulfone; although the patent proposes In order to use a variety of organic solvents as the electrolyte, the requirements of the electrolyte solvent for the dielectric constant and viscosity have not yet been resolved.

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