Water-in-salt锂离子电解液研究进展

Research progress on lithium based Water-in-salt electrolytes

与传统的商用有机锂离子电池相比,水系锂离子电池具有高安全性、成本低、环境友好等优点,但由于水的热力学窗口较窄(1.23 V),从而大大限制了其输出电压和能量密度。Water-in-salt电解液的提出将水溶液的电化学窗口拓宽到3.0V以上,为实现新型高电压水系锂离子电池提供了有利前提保证。本综述意在介绍Water-in-salt电解液及其相关衍生体系以及其在锂离子电池、锂硫电池以及混合离子电池中的相关应用拓展。与此同时,对该新体系中所引出的新的基础科学问题,包括水系固态电解质界面(SEI)膜的生长机理及锂离子的传输机制做了简单归纳和总结。

Compared with commercial organic based lithium （Li） ion batteries, aqueous lithium-ion batteries （ALIBs） present high safety, low cost and environment-friendly. However, due to the limitation of the electrochemical window of aqueous solution （1.23 V）, it is excluded the most of electrochemical couples with the output voltage above 1.5 V. The invention of the Water-in-salt （WlS） electrolyte firstly expand stable electrochemical window of the aqueous electrolyte above 3.0 V which conceives of a series of high voltage ALIBs. The review mainly summarized research progress on Water-in-salt electrolyte and its relative following works, including the derivative electrolytes such as Water-in-bisalt electrolyte and its expanding applications on Li ion batteries, lithium-sulfur batteries and hybrid-ion batteries, and meanwhile introduces the fundamental investigation on the solid electrolyte interphase （SEI） formation mechanism and Li ion transport mechanism in WIS electrolytes.