固态金属锂负极界面研究进展

Review on interfaces in solid-state lithium metal anodes

开发下一代高安全性、高能量密度电池是电动汽车、可穿戴便携电子设备与可再生能源高效利用的关键。固态金属锂电池是极有希望的下一代电池体系。本文首先综述了固态电解质与界面特性,包括固态电解质中的离子传输机理和固态电解质分类,指出金属锂电极与固态电解质之间有限的固-固界面接触是固态金属锂电池实用化的重要挑战,其界面演变特性主导了固态电池的性能表现。界面演变是机械-化学-电化学耦合的过程。其次,文章综述了电池界面失效机制与构筑策略,指出界面失效包括枝晶状沉积引发的电池短路与空穴累积、副反应导致的电化学界面脱触等,使用界面润湿剂、引入界面缓冲层或构造三维多孔骨架结构化电极等是解决界面问题的重要手段。最后,文章总结指出,固态金属锂电池仍有巨大的进步空间,先进的理论研究和表征手段为进一步认识和理解固-固界面提供了新的机遇,通过界面化学、材料科学、系统工程等领域的交叉共融,有望共同推动下一代高安全、高能量密度固态储能技术的发展。

Developing next-generation batteries with high safety and energy density are crucial for electric vehicles,portable electronics and renewable energy utilization.This paper firstly summarizes the solid-state electrolytes and interfacial properties,including the ion transportation mechanisms and classification of solid-state electrolytes.The limited solid-solid interfacial contacts between Li metal anodes and solid-state electrolytes are major obstacles for the application of solid-state Li metal batteries.The interface evolution properties dominate the performances of solid-state batteries,which are mechanical-chemical-electrochemical coupled processes.Afterwards,this paper reviews the battery interface failure mechanisms and construction strategies,indicating that interface failures include battery short circuits induced by dendritic Li deposition and contact loss caused by voids accumulation and interfacial side reactions.Strategies towards solving the interfacial issues include the use of wetting agents,the introduction of a buffer layer and the construction of porous scaffolds for a structured electrode.The paper concludes that,advanced computation techniques and characteristic methods afford an emerging opportunity to understand the solid-solid interfaces and develop solid-state Li metal batteries with great prospects.The synergism from interface chemistry,materials science and systems engineering will jointly promote the development of next-generation energy storage devices with enhanced safety and energy density.