Electrolyte additive, application and non-aqueous electrolyte containing additive

Abstract

The invention relates to an electrolyte additive, an application thereof and a non-aqueous electrolyte containing the additive. The electrolyte additive contains an unsaturated cyclic phosphate compound. The unsaturated cyclic phosphate compound is selected from at least one of compounds with a structure as shown in a formula I, wherein R is respectively selected from C1-C5 straight-chain or branched-chain alkane, C1-C10 straight-chain or branched-chain unsaturated alkyl (including alkylene, alkyne and aryl), or alkyl containing C1-C5 straight-chain or branched-chain substituted by halogen. According to the electrolyte additive and the electrolyte using the additive provided by the invention, the electrolyte can solve the main problems faced by a lithium ion battery when the lithium ion battery is used under an extreme condition, and the high-temperature cycle performance and the high-temperature storage performance of the battery are remarkably improved.

Description

technical field [0001] The invention belongs to the field of lithium-ion batteries, and relates to electrolyte additives and applications for improving the cycle performance and storage performance of lithium-ion batteries, and non-aqueous electrolytes containing the additives. Background technique [0002] At present, energy shortage and environmental pollution have become worldwide problems. In order to alleviate these problems, it is imperative to develop new energy vehicles to replace traditional fuel vehicles. In view of the advantages of high energy density, long life and environmental friendliness of lithium-ion batteries, in recent years, with the continuous reduction of production costs of lithium-ion batteries and the rapid development of related technologies, it has been more and more widely used in the field of new energy vehicles. It is considered to be the most potential technology to replace traditional fuel vehicles. [0003] During the first charging proces...

AI Technical Summary

Problems solved by technology

At high voltage, the positive electrode active material is in a lithium-deficient state, which has strong oxidative properties, and it is easy to oxidize and decompose the electrolyte in direct contact with it, accompanied by the generation of a large amount of gas; in addition, in an excessive lithium-deficient state The positive electrode active material is relatively unstable and prone to some side reactions (such as oxygen release, phase transition, transition metal ion dissolution, etc.), which makes the performance of lithium-ion batteries deteriorate rapidly; similarly, high temperature will greatly accelerate the deterioration speed

[0004] Disadvantages of the prior art: when the lithium-ion battery is used under extreme conditions (such as high voltage / high temperature), its performance will deteriorate rapidly; at the same time, under extreme conditions, the interior of the lithium-ion battery is unstable, and its safety performance is also greatly affected. test

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