Non-aqueous electrolyte and lithium secondary battery of using same

Abstract

The invention belongs to the field of lithium-ion battery materials, and discloses a non-aqueous electrolyte and a lithium secondary battery of using the same. The non-aqueous electrolyte comprises a non-aqueous organic solvent, a lithium salt and an additive, wherein the additive comprises at least one of a pyridineboronic acid pinacol ester compound and a phenylboronic acid pinacol ester compound. The pyridineboronic acid pinacol ester compound and the phenylboronic acid pinacol ester compound are used for the electrolyte for the lithium secondary battery for the first time, the variety and the selection range of the additive of the electrolyte are enriched, and the cycle performance, the rate capability and the high-and-low temperature performance of the lithium secondary battery can be obviously improved by the obtained electrolyte.

Description

technical field [0001] The invention belongs to the field of lithium ion battery materials, and in particular relates to a nonaqueous electrolytic solution and a lithium secondary battery using the electrolytic solution. Background technique [0002] Due to the advantages of high energy density, high output voltage, long cycle life, and low environmental pollution, lithium secondary batteries have extremely important applications in the fields of electronic products, electric vehicles, aerospace, and energy storage. However, in recent years, lithium secondary batteries have put forward higher requirements for energy density, cycle performance, high and low temperature performance, and rate performance. [0003] As an important part of the lithium secondary battery, the electrolyte is known as the "blood" of the lithium secondary battery and is an important factor affecting the performance of the lithium secondary battery, and the additive of the electrolyte is a very critica...

AI Technical Summary

Problems solved by technology

[0004] However, sulfonates and nitriles are well-known additives in lithium secondary battery electrolytes, and most of them have more or less defects

For example, 1,3-propiolactone sulfonate, which is the most widely used, has been listed as a restricted substance by the European Union; such as the methylene disulfonate of the above-mentioned patent, although it can improve the high and low temperature performance of the battery, its own The stability is extremely poor, which significantly shortens the shelf life of the electrolyte; such as succinonitrile, adiponitrile, hexanetrinitrile and a series of nitrile substances, the passivation film formed by them has a large impedance, which is not conducive to the rate discharge and low temperature of the battery. discharge

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