Electrolyte functional additive, non-aqueous lithium-ion battery electrolyte containing additive and lithium-ion battery

Abstract

The invention discloses a non-aqueous lithium-ion electrolyte additive, an electrolyte and a lithium-ion battery. The electrolyte comprises an electrolyte salt, a non-aqueous organic solvent and a functional additive, wherein the chemical general formula of the functional additive is AXB, and A, B and X represent chemical formulas. By adding the functional additive, a compact and uniform solid electrolyte interface (SEI) membrane with high lithium-ion conductivity can be promoted to be formed during the initial formation of an electrolyte system, the current of the battery is uniformly distributed during the charging and discharging period, the ion conductivity of a lithium ion is increased, the initial capacity development, the normal-temperature cycling performance and rate capability, the high-temperature cycling performance and storage performance and the low-temperature discharging performance and rate capabilityof a lithium secondary battery are further improved, moreover, lithium dentrite formation can be reduced, and the problem of lithium deposition caused by serious polarization during the low temperature charging and discharging processes is relieved.

Description

technical field [0001] The invention relates to a lithium ion battery, and more specifically, the invention relates to a nonaqueous electrolyte functional additive, a nonaqueous electrolyte and a lithium ion battery using the nonaqueous electrolyte. Background technique [0002] With the rapid development of increasingly smaller and lighter portable electronic devices, there is an increasing demand for small, lightweight, thin and high-performance batteries that provide power for these portable electronic devices. However, as the battery pursues small volume and high energy density, the compaction density of the positive and negative electrodes is continuously increased or the high-capacity negative electrode material with poor cycle performance is used, which also brings a series of performance problems of the battery, such as poor cycle performance. , Poor high temperature performance, poor low temperature performance and rate performance, easy to precipitate lithium durin...

AI Technical Summary

Problems solved by technology

In a low-temperature environment, if the formed SEI film is too thick and the film resistance is high, lithium ions cannot migrate through, and lithium precipitation will occur; during high-temperature cycling, if the formed SEI film is not dense and stable, the SEI film will Gradually dissolve or rupture, causing the exposed negative electrode to continue to react with the electrolyte, which consumes the electrolyte and reduces the battery capacity

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