High-voltage-resistant lithium ion battery non-aqueous electrolyte and ternary high-voltage lithium ion battery

Abstract

The invention belongs to the technical field of lithium ion batteries, and discloses a high-voltage-resistant lithium ion battery non-aqueous electrolyte and a ternary high-voltage lithium ion battery. The high-voltage-resistant non-aqueous electrolyte of the lithium ion battery comprises a non-aqueous organic solvent, an electrolyte lithium salt and an additive, wherein the additive comprises a conventional additive and an additive as shown in a compound (1). Compared with the prior art, through the combined action of the combined conventional additive and the additive with the structure shown in the formula (I), a film can be formed on the surface of the positive electrode material, generation of cracks in particles of the positive electrode material in the circulation process is inhibited, dissolution of transition metal elements at high temperature is reduced, and an SEI film can be formed on the surface of the negative electrode material; and meanwhile, the interface impedance canbe reduced, so that the cycle performance, the rate capability and the low-temperature performance of the ternary high-voltage lithium ion battery are effectively improved.

Description

technical field [0001] The invention relates to the technical field of lithium-ion batteries, in particular to a non-aqueous electrolyte solution for a high-voltage lithium-ion battery and a ternary high-voltage lithium-ion battery. Background technique [0002] Lithium-ion batteries are widely used in 3C digital products, power tools, electric vehicles, aerospace and other fields due to their high operating voltage, high energy density, long life, wide operating temperature range, and environmental friendliness. In the field of 3C digital, in recent years, mobile electronic devices, especially smart phones, have developed rapidly towards lighter and thinner, which puts forward higher requirements for the energy density of lithium-ion batteries. [0003] Compared with commercial lithium cobalt oxide materials, ternary materials have higher theoretical and actual gram capacities, and ternary materials are becoming more and more popular in the field of general rudder applicati...

AI Technical Summary

Problems solved by technology

However, there will be certain defects in the positive electrode material under high voltage. For example, the high-voltage positive electrode active material has a strong oxidation property in the lithium-deficient state, which makes the electrolyte easy to be oxidized and decomposed, and produces a large amount of gas; in addition, the high-voltage positive electrode The active material itself is also very unstable in the state of lithium deficiency, and some side reactions are prone to occur, such as the release of oxygen, the dissolution of transition metal ions, etc., causing the transition metal ions to break away from the crystal and enter the electrolyte as the reaction progresses to catalyze the decomposition and dissolution of the electrolyte. Damage the passivation film of the active material, and transition metal lithium ions will also occupy the lithium ion migration channel of the passive film on the surface of the negative electrode material, hindering the migration of lithium ions, thereby affecting the service life of the battery. This negative effect will be more pronounced when used under

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