Anti-overcharge electrolyte and lithium ion battery containing electrolyte

Abstract

The invention discloses an anti-overcharge electrolyte and a lithium ion battery containing the electrolyte and relates to the technical field of lithium ion batteries. The anti-overcharge electrolytecomprises an anti-overcharge additive, wherein the anti-overcharge additive is composed of at least one of triphenoxy cyclotriboroxane and derivatives thereof, and the structural formula of the anti-overcharge additive is shown in the specification, triphenoxy cyclotriboroxane or derivatives thereof are adopted as the anti-overcharge additive, the anti-overcharge additive is added into an electrolyte, and polymerization reaction occurs only at a relatively high voltage of 4.5 V or above. The electrolyte is suitable for the lithium ion battery of a high-voltage material system, has less influence on the cycle performance, impedance and other electrochemical properties of the lithium ion battery, has very good overcharge prevention performance, and improves the safety performance of the lithium battery, especially the lithium battery of the high-voltage material system.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to an anti-overcharge electrolyte and a lithium ion battery containing the electrolyte. Background technique [0002] Lithium-ion batteries have significant advantages such as high energy density, low self-discharge rate, wide operating temperature range, long cycle life, and no memory effect. They are widely used in 3C digital, new energy vehicles, energy storage power stations, aerospace and other fields. Electrolyte is an essential and important part of lithium-ion batteries, which has an important impact on its capacity, internal resistance, cycle, rate, safety and other properties. However, for new energy vehicle power batteries and large energy storage system batteries In other words, only when a large number of lithium-ion battery cells are connected in series and parallel can the rated working voltage and capacity be reached. Due to the difference in the initi...

AI Technical Summary

Problems solved by technology

[0004] From the perspective of the existing technology, although the above electropolymerization additives such as tert-butylbenzene, biphenyl, and cyclohexylbenzene can effectively inhibit battery overcharge, on the one hand, most of the additives will damage the cycle performance of the battery after being added, increasing the battery life. Battery impedance; on the other hand, many additives undergo electropolymerization within the normal operating voltage of lithium batteries, which often limits their large-scale use in high-voltage material systems such as ternary lithium-ion batteries

Therefore, there is an urgent need to find an overcharge protection additive, which can not only avoid the anti-overcharge additive from damaging the battery cycle performance and increase the impedance of the lithium battery, but also be suitable for solving the safety problem of the high-voltage material system lithium battery.

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