锂硫电池电解液多功能添加剂:作用机制及先进表征

Electrolyte multifunctional additives of lithium-sulfur battery:Mechanism of action and advanced characterization

锂硫电池作为一种新型清洁能源存储转化装置具有高理论比容量、环境友好等优点,是现如今储能领域中的重点研究对象。但电池充放电时氧化还原反应动力学缓慢及长链多硫化锂的穿梭效应影响电池循环寿命。电解液是锂硫电池的重要组成部分,在充放电过程中肩负着离子转移和电子传递的作用。近年来,锂硫电池多功能电解液添加剂的研究脱颖而出,在电解液中引入添加剂可实现催化多硫化锂转化反应、保护金属锂、调控界面等功能。本文通过对近期相关文献的探讨,综述了利用电解液添加剂提升电池充放电反应动力学和抑制多硫化物穿梭效应的策略,着重介绍了无机共盐、有机含硫、有机含氟、有机含硒/碲添加剂,重点分析了上述添加剂对多硫化物调控的作用机制。在探究电池内部的反应机理方面,介绍了多种具有实时性和精准性的原位表征仪器在锂硫电池中的应用。综合分析了锂硫电池电解液多功能添加剂的研究进展,针对多种类型添加剂的作用机制进行讨论;指出原位表征技术对揭示催化机理和设计功能添加剂的指导作用,并对锂硫电池电解液添加剂未来发展方向进行展望。

The lithium-sulfur battery,heralded as a promising clean energy storage device,boasts high theoretical specific capacity and environmental friendliness,making them a focal point in energy storage research.However,challenges such as slow kinetics in redox reactions and the shuttle effect of long-chain lithium polysulfides significantly impact the battery life.The electrolyte,which plays a pivotal role in ion and electron transfer during charge and discharge,is a critical component of the lithium-sulfur battery.Recent advancements in lithium-sulfur batteries have highlighted the significance of multifunctional electrolyte additives.The incorporation of additives into the electrolyte has proven instrumental in catalyzing lithium polysulfide conversion reactions,safeguarding metal lithium,and regulating the interface.This article provides a comprehensive review of strategies employed to enhance reaction kinetics and inhibit the shuttle effect by using electrolyte additives,drawing upon the recent literature.Specifically,this article focuses on key additives,including inorganic co-salts,organic sulfur,organic fluorine,and organic selenium/tellurium.The discussion delves into the mechanisms by which these additives regulate polysulfides.To gain a deeper understanding of the internal workings of the battery,this article introduces various in-situ characterization instruments known for their real-time precision in lithium-sulfur batteries.The research progress of multifunctional additives for lithium-sulfur battery electrolytes undergoes a comprehensive analysis,elucidating the mechanism of action for different additive types.The article underscores the guiding role of in-situ characterization technology in revealing catalytic mechanisms and designing functional additives.In addition,it offers a prospective outlook on the future development directions of electrolyte additives for lithium-sulfur batteries.