Non-aqueous electrolyte for lithium ion battery and lithium ion battery thereof

Abstract

The invention discloses a non-aqueous electrolyte for a lithium ion battery and the lithium ion battery. The electrolyte comprises electrolyte lithium salt lithium hexafluorophosphate, a non-aqueous organic solvent and an additive; the additive comprises an additive A which is a phosphamide compound with a structural formula (1); the structural formula (1) is shown in the specification, in the structural formula (1), each of R1 to R6 is respectively and independently one of alkane groups or halogenated alkane groups with the carbon atom number of 1 to 5; and the additive amount is 0.1%-10% ofthe total weight of the electrolyte. The additive A provided by the invention can form a stable complexing state with hexafluorophosphate ions in a lithium hexafluorophosphate electrolyte system, so that the hexafluorophosphate anions exist more stably, battery side reactions caused by decomposition of the hexafluorophosphate anions are reduced, and the stability of the electrolyte is improved; and the electrolyte can be combined with other common additives to play a synergistic role, so that the lithium ion battery adopting the electrolyte has better electrical cycle performance.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery electrolytes, in particular to a non-aqueous electrolyte for lithium-ion batteries and a lithium-ion battery thereof. [0002] technical background [0003] Since the advent of commercial lithium-ion batteries in the 1990s, lithium-ion batteries have been widely used in 3C consumer electronics such as mobile phones, cameras, and laptops due to their advantages such as high voltage, high specific energy, no memory effect, and long cycle life. field. Lithium-ion batteries are mainly composed of positive electrodes, negative electrodes, separators, and electrolytes. The performance of lithium-ion batteries, especially the performance of high-voltage lithium-ion batteries, is mainly determined by the composition and properties of the positive electrode active material and electrolyte. In order to develop a suitable high-performance electrolyte, it is often added to the electrolyte Suitabl...

AI Technical Summary

Problems solved by technology

Due to the instability of the hexafluorophosphate ion, in the presence of trace amounts of water and high temperature, it will continue to decompose and react with solvents to produce a series of side reactions, which will damage the high temperature and cycle performance of lithium-ion batteries.

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