Zhao Meng, Li Bo-Quan, Peng Hong-Jie, Yuan Hong, Wei Jun-Yu, Huang Jia-Qi
School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China.
Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, P. R. China.
Angew Chem Int Ed Engl. 2020 Jul 27;59(31):12636-12652. doi: 10.1002/anie.201909339. Epub 2020 Mar 17.
The development of energy-storage devices has received increasing attention as a transformative technology to realize a low-carbon economy and sustainable energy supply. Lithium-sulfur (Li-S) batteries are considered to be one of the most promising next-generation energy-storage devices due to their ultrahigh energy density. Despite the extraordinary progress in the last few years, the actual energy density of Li-S batteries is still far from satisfactory to meet the demand for practical applications. Considering the sulfur electrochemistry is highly dependent on solid-liquid-solid multi-phase conversion, the electrolyte amount plays a primary role in the practical performances of Li-S cells. Therefore, a lean electrolyte volume with low electrolyte/sulfur ratio is essential for practical Li-S batteries, yet under these conditions it is highly challenging to achieve acceptable electrochemical performances regarding sulfur kinetics, discharge capacity, Coulombic efficiency, and cycling stability especially for high-sulfur-loading cathodes. In this Review, the impact of the electrolyte/sulfur ratio on the actual energy density and the economic cost of Li-S batteries is addressed. Challenges and recent progress are presented in terms of the sulfur electrochemical processes: the dissolution-precipitation conversion and the solid-solid multi-phasic transition. Finally, prospects of future lean-electrolyte Li-S battery design and engineering are discussed.
作为实现低碳经济和可持续能源供应的变革性技术，储能设备的发展受到了越来越多的关注。锂硫（Li-S）电池因其超高的能量密度而被认为是最有前途的下一代储能设备之一。尽管在过去几年中取得了非凡的进展，但Li-S电池的实际能量密度仍远不能令人满意，无法满足实际应用的需求。考虑到硫的电化学高度依赖于固-液-固多相转换，电解液的量在Li-S电池的实际性能中起着主要作用。因此，对于实际的Li-S电池来说，低电解液/硫比的贫电解液体积是必不可少的，然而在这些条件下，尤其是对于高硫负载的阴极，要在硫动力学、放电容量、库仑效率和循环稳定性方面实现可接受的电化学性能极具挑战性。在这篇综述中，讨论了电解液/硫比对Li-S电池实际能量密度和经济成本的影响。从硫的电化学过程：溶解-沉淀转化和固-固多相转变方面介绍了挑战和近期进展。最后，探讨了未来贫电解液Li-S电池设计和工程的前景。
