Research Progress and Perspectives of Localized High-concentration Electrolytes for Secondary Batteries

Abstract

The electrolyte, which is an important medium of ion conduction for secondary batteries, plays a crucial role in improving the cycling performance and safety performance of secondary batteries. Localized high-concentration electrolytes, which are formed by adding "diluent" into high-concentration electrolyte, not only reserve the outstanding properties of high-concentration electrolytes but also possess low viscosity, excellent wettability and low cost, promising broad application prospect. Localized high-concentration electrolytes have already played a part in flame-retardant lithium battery, high-voltage lithium battery, low-temperature lithium battery, lithium sulfur battery and sodium battery. Herein, this paper mainly reviews the types and preparation of localized high-concentration electrolytes and their functional mechanism and research status in various secondary batteries. We discuss the challenges and future development of localized high-concentration electrolytes and have the outlook at the end of the paper.