Lithium ion battery electrolyte containing unsaturated bond silane additive and lithium ion battery

Abstract

The invention discloses a lithium ion battery electrolyte containing an unsaturated bond silane additive, which comprises an electrolyte lithium salt, a non-aqueous organic solvent and a film-forming additive, and the film-forming additive comprises an unsaturated bond-containing silane additive with a structure shown in a formula (I). The invention further discloses a lithium ion battery. The lithium ion battery comprises a positive plate, an isolating membrane, a negative plate and the lithium ion battery electrolyte containing the unsaturated bond silane additive. According to the invention, the formula of the electrolyte is optimized, all the components have a synergistic effect, the advantages of the components can be exerted, the defects of the components can be mutually inhibited, and the cycle performance of the lithium ion battery and the capacity retention rate after high-temperature storage are remarkably improved.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a lithium ion battery electrolyte containing an unsaturated bond silane additive and a lithium ion battery. Background technique [0002] Lithium-ion batteries are widely used in 3C digital products, power tools, electric vehicles and other fields due to their advantages such as high working voltage, high energy density, long life and environmental friendliness. Especially in the 3C digital field, in recent years, the development trend of mobile electronic devices such as mobile power banks for smartphones is lighter and thinner, making lithium-ion batteries more and more popular. [0003] As one of the main materials in lithium-ion batteries, electrolyte plays an indispensable role and is known as the "blood" of lithium-ion batteries. However, the most critical part of the lithium-ion battery electrolyte is additives, such as negative electrode film-forming additi...

AI Technical Summary

Problems solved by technology

The disadvantage is that it is found through experiments that when silane contains unsaturated bonds, especially when it contains two or more unsaturated bonds, when the added amount is greater than 1%, and no other low-impedance substances are added for combination, the impedance of the battery will increase. Large, the first effect is reduced, and the gram capacity is low, etc.

[0005] Therefore, there is an urgent need to develop a new type of unsaturated bond-containing silane additive, which can not only give full play to the advantages of the unsaturated bond-containing silane additive, but also effectively solve the problem that the unsaturated bond-containing silane additive has too much impedance and thus affects the electrochemical performance of lithium-ion batteries. question

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