A lithium metal battery electrolyte and a lithium metal battery and a lithium sulfur battery

Abstract

In order to improve the cycle performance of the battery, A lithium metal battery electrolyte and a lithium metal battery and a lithium sulfur battery are disclose, A lithium metal battery electrolyteincluding solvents and lithium salts, the lithium salt comprises a lithium salt I, lithium salt II, lithium salt III, The mass percentages of each component in the electrolyte are: 40 to 85 percent of solvent, 10 to 50 percent of lithium salt I, 0.1 to 3 percent of lithium salt II, 0.1 to 10 percent of lithium salt III, wherein the solvent is an arbitrary combination of an organic heterocyclic compound containing an oxygen group element on a ring, the lithium salt I is lithium bis-trifluoromethanesulfonimide (LiTFSI), the lithium salt II is lithium nitrate (LiNO3), and the lithium salt III isone or a combination of one or several of a lithium salt containing boron and a lithium salt containing phosphorus; A lithium metal battery comprise a positive electrode, a lithium-containing negative electrode, a separator and that electrolyte; A lithium-sulfur battery comprise a sulfur-containing positive electrode, a lithium-containing negative electrode, a membrane and that electrolyte; The invention belongs to the field of lithium ion batteries and improves the cycling performance of lithium sulfur batteries.

Description

technical field [0001] The invention belongs to the field of lithium batteries, in particular to a lithium metal battery electrolyte, a lithium metal battery and a lithium-sulfur battery. Background technique [0002] A lithium-sulfur battery consists of a positive electrode containing electroactive sulfur, a negative electrode containing lithium, an electrolyte, and a separator. The theoretical specific energy of lithium-sulfur batteries is as high as 2600Wh / kg, and the actual specific energy is higher than that of current commercial lithium-ion batteries. The significant advantages in specific energy make lithium-sulfur batteries have good application prospects in special power sources, electric vehicles, high-altitude aircraft, deep-sea submarines and other fields. [0003] A notable feature of lithium-sulfur batteries is that lithium polysulfides, an intermediate product, will be generated during the electrochemical reaction of the sulfur positive electrode, and lithium...

AI Technical Summary

Problems solved by technology

In the electrochemical reaction, the positive electrode of the lithium-sulfur battery will have polysulfide ions dissolved into the electrolyte, and if a carbonate electrolyte is used, the polysulfide ions will react with the carbonate solvent, making the battery capacity extremely poor and Unable to perform charge and discharge cycles

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