Lithium ion battery electrolyte and lithium ion battery

Abstract

The invention is applicable to the field of a lithium ion battery, and provides lithium ion battery electrolyte. The lithium ion battery electrolyte comprises lithium salt, a non-aqueous organic solvent and an additive. The additive comprises polysiloxane. A molecular structural formula of the polysiloxane is as follows: (with reference to the specification), wherein n is in a range of 1 to 3, and R1, R2, R3 and R4 respectively are any one of C1 to C3 alkyl groups. In the lithium ion battery electrolyte provided by the invention, by adding the polysiloxane, decomposition of LiPF6 can be effectively inhibited, so that stability of the lithium ion battery electrolyte is obviously improved, and meanwhile, the conductivity of the lithium ion battery electrolyte is improved. The lithium ion battery electrolyte provided by the invention can obviously improve high-temperature cycling performance and safety performance of the lithium ion battery.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, in particular to a lithium ion battery electrolyte and a lithium ion battery. Background technique [0002] As the degree of informatization of modern life continues to increase, portable electronic devices such as notebook computers, mobile phones, and video cameras are used more and more. Lithium-ion secondary batteries have been widely used in the field of portable electronic products due to their advantages of high energy density, no memory effect, and environmental friendliness, and have great application potential in the field of electric vehicles. [0003] However, the battery capacity of lithium-ion batteries decays rapidly at high temperatures, resulting in significantly shortened battery life. The main reason for the rapid decline in the performance of lithium-ion batteries at high temperatures comes from the electrode material itself and the electrolyte system. The electrolyte sys...

AI Technical Summary

Problems solved by technology

LiPF 6 It is easy to decompose under high temperature conditions to produce LiF and PF 5 , where the generation of LiF not only consumes lithium ions, causing the attenuation of battery capacity, but also increases the overall impedance of the battery because LiF is an insulator between electrons and lithium ions; and the generated PF 5 It is easy to cause further side reactions of carbonate organic solvents, thereby accelerating the decay of battery life

Therefore, LiPF 6 The use of the battery will have a lot of adverse effects on the high temperature stability of the battery

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