An ionic liquid-modified ether-based electrolyte and its preparation method and application

Abstract

The present invention discloses an ionic liquid-modified ether-based electrolyte and its preparation method and application, belonging to the field of lithium battery technology. The modified ether-based electrolyte includes a basic electrolyte and ionic liquid additives. The basic electrolyte is a 1M lithium di-trifluoromethanesulfonylimide solution, with a solvent of a volume ratio of 1:1 of ethylene glycol dimethyl ether and 1,3-dioxolane, and containing 1-5 wt% lithium nitrate in the solution; the amount of ionic liquid additives added is 0.5-5 wt%. The preparation method of the modified ether-based electrolyte: in an argon glove box (H2O<0.1 ppm, O2<0.1 ppm), adding the ionic liquid additives drop by drop to the basic electrolyte, and stir magnetically (with 500 rpm, for 2 h) to form a uniform transparent solution. The modified ether-based electrolyte is suitable for various lithium metal batteries, can effectively improve the coulombic efficiency, cycle life and safety of lithium metal batteries, and enable lithium metal batteries to operate stably in a wider range of environmental temperatures.