Electrolyte of lithium ion power battery

Abstract

The invention belongs to the technical field of a lithium ion battery, in particular relates to an electrolyte of a lithium ion power battery. In the electrolyte, at least two of vinylene carbonate, tetraethylammonium tetrafluoroborate, triethylmethylammonium tetrafluoroborate and fluoboric acid volution quaternary ammonium salt are taken as additives, and the additives account for 0.01-5wt%. The content of hydrofluoric acid of the electrolyte can be controlled to a low level even to be zero; the tetrafluoroborate ammonium salt is beneficial for improving the dissociation of anions and cations and also can be taken as a constituent of a solid electrolyte interface (SEI) membrane of the battery for use; the cations are tetrafluoroborate and are ingredient of lithium tetrafluoroborate of a lithium salt for the battery electrolyte; and the charging and discharging cycle performance of the battery is improved. By combining respective characteristics of a supercapacitor electrolyte and the electrolyte of the lithium ion battery, high conductivity of the electrolyte for the lithium ion battery is achieved; and with the initial charging and discharging process of the lithium ion battery, the structure of the SEI membrane is improved, and high capacity and a circulation effect of the lithium ion battery are achieved.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to an electrolyte solution for lithium ion power batteries. Background technique [0002] For a long time, the depletion of fossil energy and environmental pollution have been the main problems faced by countries all over the world. As a green and clean energy explored and developed in the 21st century, lithium-ion batteries have the advantages of environmental protection, high energy density, light weight, and safety. It is widely used in civil power supply. With the continuous expansion of the application range of lithium-ion batteries, especially the rapid progress in the field of power batteries such as electric vehicles, the different requirements for the environment, temperature and safety factors have placed stringent requirements on the electrolyte system. [0003] At present, the electrolyte solution for non-aqueous secondary lithium batteries usu...

AI Technical Summary

Problems solved by technology

For example, adding nitrile (NC-R-CN) additives alone in the electrolyte additives can improve the high-temperature storage performance of the battery; adding vinylene carbonate (VC) additives alone can improve the battery cycle performance; adding fluoroethylene carbonate alone The ester (FEC) additive can prolong the cycle life of the battery; adding 1,3-propane sultone (PS) additive alone can improve the high temperature cycle performance of the battery; but they have advantages and cannot be used alone because of some disadvantages

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