An electrolyte solution for improving the high-voltage performance of lithium batteries

Abstract

The invention provides an electrolyte for improving the high voltage performance of a lithium battery. The electrolyte comprises four components of a lithium salt, a carbonic ester and / or ether organic solvent, a high voltage additive and other functional additives, wherein the molar concentration ranges of the lithium salt and the high voltage additive are both 0.001-2 mol / L, and the molar concentration ranges of other functional additives are 0-0.5 mol / L. According to the electrolyte provided by the invention, the high voltage additive is added into the electrolyte of the lithium battery to improve the stability of the electrolyte at the high voltage, thereby being favorable for prolonging the high voltage cycle life of the lithium battery and inhibiting the swelling of the lithium battery.

Description

technical field [0001] The invention belongs to the technical field of chemical materials, and in particular relates to an electrolyte for improving the high-voltage performance of a lithium battery. Background technique [0002] As the marketization of lithium-ion batteries continues to deepen, people's expectations for lithium-ion batteries are getting higher and higher. Currently commercialized lithium-ion batteries have been difficult to meet the needs of practical applications, such as portable devices such as mobile phones, video cameras, and notebook computers. With the application in electric vehicles, cordless power tools and military, higher requirements are placed on the energy density of lithium-ion batteries, and LiNiMnO 4 , LiNiCoMnO 2 and LiCoPO 4 Li-ion deintercalation reactions can occur at higher voltages (greater than 4.2 V), thus bringing new hope for improving the energy density of Li-ion batteries. However, the electrolyte of lithium-ion batteries i...

AI Technical Summary

Problems solved by technology

However, although a large amount of fluorinated solvents solves the problem of electrolyte withstand voltage, the conductivity of the electrolyte is reduced, and the resistance of the SEI film is further increased, the charge and discharge performance is reduced, and the gas generation is very significant, and the battery expands greatly.