An all-ionic liquid electrolyte and a lithium battery containing the electrolyte

Abstract

The invention discloses a total ionic liquid electrolyte and a lithium battery containing the electrolyte. The total ionic liquid electrolyte comprises a solvent, an additive and a lithium salt. The solvent is a total ionic liquid, and the ionic liquid is a main solvent and a surface active ionic liquid is an auxiliary solvent. The anion of the electrolyte system is bis (trifluoromethyl) sulfonimide with imine conjugated system, and the cation of the electrolyte system is imidazole cation. The electrolyte provided by the invention has non-combustibility, wide temperature range of lithium ion electrolyte, and good wettability to diaphragm and electrode material. Two kinds of ionic liquids and electrolyte lithium salt in electrolyte have the same anion, which not only ensures the good compatibility between electrolytes, but also prevents the electrolyte system from deteriorating due to the ion exchange rearrangement of different anions in the electrolyte system.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to an all-ionic liquid electrolyte and a lithium battery containing the electrolyte. Background technique [0002] Due to its high voltage, high specific energy, long cycle life and excellent battery performance such as no memory effect, lithium batteries have developed rapidly since their introduction in 1990 and have become mainstream batteries in the 21st century. They are used in aviation, aerospace, navigation, communications and electronics. It has been widely used in equipment and other fields. With the rapid development of mobile electronic devices and electric vehicles, while the capacity and energy density of lithium batteries are increasing, the safety of lithium batteries has become the key to restricting their development and application. [0003] Lithium batteries currently on the market mostly use a mixed electrolyte composed of flammable organic solvents (...

AI Technical Summary

Problems solved by technology

For example, the patent document CN106920910 A replaces the polyolefin diaphragm with a safe cellulose non-woven diaphragm to improve the problem of poor wettability of the all-ionic liquid electrolyte to the polyolefin diaphragm, but does not mention the wettability of the negative electrode.

[0006] Therefore, for the lithium battery all-ionic liquid electrolyte, there is a problem that the impregnation of the ionic liquid with high viscosity into porous materials such as electrodes and separators is poor.

The non-aqueous solvents that can be used for lithium battery electrolytes are very limited, and there are many safety hazards in the commercially used carbonate solvents; there are compatibility problems between traditional surfactants and ionic liquids, and it is necessary to add carbonate non-aqueous solvents. Solvents increase the solubility of traditional surfactants

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