Lithium ion battery and electrolyte thereof

Abstract

The invention discloses lithium ion battery electrolyte. The electrolyte comprises a non-aqueous solvent and lithium salt dissolved in the non-aqueous solvent, wherein the non-aqueous solvent contains 1,4-butanediol-sulfate which is as shown in formula I, and the total mass of the 1,4-butanediol-sulfate accounts for 0.5 to 15 percent of the total mass of the non-aqueous solvent. According to the lithium ion battery electrolyte, the decomposition reaction of the electrolyte can be effectively inhibited, so that the high-temperature storage performance and the high-temperature circulating performance of the lithium ion battery can be improved, and the improvement effect can be maintained for a long time. Furthermore, the invention discloses a lithium ion battery using the lithium ion battery electrolyte. The formula I is shown in details.

Description

technical field [0001] The invention relates to a lithium-ion battery and its electrolyte, more specifically, the invention relates to a lithium-ion battery with ideal high-temperature storage performance and high-temperature cycle performance and its electrolyte. Background technique [0002] Lithium-ion batteries have the advantages of high energy density, high working voltage, long cycle life, no memory effect, and environmental friendliness. They have become the main power source of mobile consumer electronics, and their applications in electric vehicles and smart grids are becoming more and more mature. [0003] Both the positive and negative electrodes of lithium-ion batteries have high activity. For charged lithium-ion batteries, the negative electrode has high reducibility, and the positive electrode has high oxidative property. Without the protection of film-forming additives, common carbonate solvents are easily mixed with positive Negative side reactions occur. I...

AI Technical Summary

Problems solved by technology

At high temperature, the reactivity of the positive and negative electrodes of the battery is further enhanced, and the side reaction speed between the electrolyte and the electrodes is accelerated, resulting in the decomposition of the electrolyte to generate a large amount of gas, which causes the battery to expand and deform and cause damage to electrical appliances

In severe cases, due to the expansion and deformation of the battery, a short circuit occurs inside the battery or the flammable electrolyte leaks due to the bursting of the battery package, which may cause the risk of fire and other safety accidents.

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