Electrolyte for lithium ion battery and lithium ion battery comprising electrolyte

Abstract

The invention provides an electrolyte suitable for a lithium ion battery with high energy density and the lithium ion battery comprising the electrolyte. A first additive (comprising trimethylsilyl isocyanate/isocyanatopropyltriethoxysilane) and a second additive (comprising boron trifluoride methyl lithium sulfate/boron trifluoride trifluoroethyl lithium sulfate) are combined for use; isocyanategroups in the first additive can be polymerized on the surface of the positive electrode to form a passive film, meanwhile, boron trifluoride functional groups in the second additive can participate in positive electrode film formation, the synergistic effect of the isocyanate groups and the boron trifluoride functional groups plays a role in efficiently protecting the positive electrode, metal ions are inhibited from dissolving out to catalyze side reaction decomposition of electrolyte, and the high-temperature performance and overcharge prevention safety performance of the battery cell are improved.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to an electrolyte suitable for high energy density lithium ion batteries and a lithium ion battery including the electrolyte. Background technique [0002] In recent years, lithium-ion batteries have been widely used in smartphones, tablet computers, smart wearables, power tools, and electric vehicles. With the wide application of lithium-ion batteries, the usage environment and demand of consumers for lithium-ion batteries continue to increase, which requires lithium-ion batteries to have the characteristics of both high and low temperature performance. However, there are potential safety hazards in the use of lithium-ion batteries. When the battery is under some abuses such as overcharging, it is prone to serious safety accidents, fire or even explosion. [0003] As an important part of lithium-ion batteries, electrolyte has a great influence on the perf...

AI Technical Summary

Problems solved by technology

In order to solve these problems, the safety performance can be improved by adding anti-overcharge additives (such as biphenyl, etc.) to the

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