High-voltage additive and high-voltage electrolyte for lithium battery

Abstract

The invention provides a high-voltage additive and a high-voltage electrolyte for a lithium battery. The high-voltage additive is a compound containing cyclic enamine and a thiophosphonate structure;the structural formula I is shown in the specification, wherein R1 and R2 are respectively one of an alkyl group with 1-8 carbon atoms, a halogenated alkyl group, an alkenyl group with 2-8 carbon atoms, a halogenated alkenyl group, an alkynyl group with 2-8 carbon atoms, a halogenated alkynyl group, an aryl group with 6-8 carbon atoms or a halogenated aryl group. According to the high-voltage additive, a stable and compact CEI film can be formed on a positive electrode, transition metal ions on the surface of a positive electrode material are stabilized, oxygen precipitation of the positive electrode material is inhibited, and oxygenolysis of an electrolyte is reduced; and a film can be formed on the negative electrode, so that the stability of a negative electrode SEI film is improved, and the performance of the lithium battery under a high-voltage condition is improved.

Description

technical field

[0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a high-voltage additive and a high-voltage electrolyte for lithium batteries. Background technique

[0002] Since its commercialization in the 1990s, lithium batteries have been widely used due to their high energy density, high charge-discharge efficiency, low self-discharge, long service life, and environmental friendliness. At present, it has been applied to the fields of consumer electronics, aerospace, military, electric tools and electric vehicles. With the development of technology, whether it is in the field of consumption or in the field of power batteries, people have higher and higher requirements for the endurance of lithium-ion batteries, and the development of lithium batteries with high energy density (mass energy density and volume energy density) has become the key. The development of high-energy-density lithium batteries can be charged in ...

Images