Electrolyte and lithium ion battery comprising the same

Abstract

The application relates to an electrolyte and a lithium ion battery comprising the electrolyte. The electrolyte comprises a lithium salt, an organic solvent and additives. The additives comprise difluoro lithium phosphate and a cyclic sulphate ester compound. The electrolyte provided by the application is applied to the lithium ion battery. Specifically, after the electrolyte is applied to the lithium ion battery whose pole piece has heavy coating weight at the single-sided active substance layer, not only high-temperature cycle performance of the lithium ion battery is improved, but also the rate capability and the low-temperature discharging performance of the lithium ion battery is improved.

Description

technical field [0001] The present application relates to the technical field of lithium-ion batteries, in particular, to an electrolyte and a lithium-ion battery including the electrolyte, in particular, the electrolyte is suitable for lithium-ion batteries with a high coating amount of active materials on pole pieces . Background technique [0002] In the rapidly developing information age, the demand for mobile phones, notebooks, cameras and other electronic products is increasing year by year, and lithium-ion batteries have been widely used in these fields. At the same time, lithium-ion batteries have also been actively developed in the fields of electric vehicles, hybrid vehicles, and energy storage equipment. [0003] As the working power source of electronic products, lithium-ion batteries have outstanding characteristics such as high energy density, no memory effect, and high working voltage, and are gradually replacing traditional Ni-Cd batteries and MH-Ni batterie...

AI Technical Summary

Problems solved by technology

[0005] 1. Develop high-voltage cathode materials, but the current cathode materials used above 4.4V are not perfect, and some electrolytes are unstable under high voltage;

[0006] 2. Adopt new high-capacity materials, such as silicon materials, but the silicon materials have serious expansion, low Coulombic efficiency in the first week, and low cycle stability;

Although this method has high application feasibility, the improvement of the coating weight of the active material on the unit current collector will lead to serious deterioration of the kinetics of the lithium-ion battery, for example, it will seriously affect the mobility of lithium ions, so that lithium Ion batteries have poor rate performance and low temperature performance

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