Bi Chen-Xi, Zhao Meng, Hou Li-Peng, Chen Zi-Xian, Zhang Xue-Qiang, Li Bo-Quan, Yuan Hong, Huang Jia-Qi
School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China.
Adv Sci (Weinh). 2022 Jan;9(2):e2103910. doi: 10.1002/advs.202103910. Epub 2021 Nov 16.
Lithium-sulfur (Li-S) battery is identified as one of the most promising next-generation energy storage systems due to its ultra-high theoretical energy density up to 2600 Wh kg . However, Li metal anode suffers from dramatic volume change during cycling, continuous corrosion by polysulfide electrolyte, and dendrite formation, rendering limited cycling lifespan. Considering Li metal anode as a double-edged sword that contributes to ultrahigh energy density as well as limited cycling lifespan, it is necessary to evaluate Li-based alloy as anode materials to substitute Li metal for high-performance Li-S batteries. In this contribution, the authors systematically evaluate the potential and feasibility of using Li metal or Li-based alloys to construct Li-S batteries with an actual energy density of 500 Wh kg . A quantitative analysis method is proposed by evaluating the required amount of electrolyte for a targeted energy density. Based on a three-level (ideal material level, practical electrode level, and pouch cell level) analysis, highly lithiated lithium-magnesium (Li-Mg) alloy is capable to achieve 500 Wh kg Li-S batteries besides Li metal. Accordingly, research on Li-Mg and other Li-based alloys are reviewed to inspire a promising pathway to realize high-energy-density and long-cycling Li-S batteries.
锂硫（Li-S）电池因其高达2600 Wh/kg的超高理论能量密度而被视为最具前景的下一代储能系统之一。然而，锂金属负极在循环过程中会发生剧烈的体积变化，受到多硫化物电解质的持续腐蚀，并形成枝晶，导致循环寿命有限。鉴于锂金属负极是一把双刃剑，既能实现超高能量密度，又会限制循环寿命，因此有必要评估锂基合金作为负极材料来替代锂金属，以制造高性能锂硫电池。在本论文中，作者系统地评估了使用锂金属或锂基合金构建实际能量密度为500 Wh/kg的锂硫电池的潜力和可行性。通过评估目标能量密度所需的电解液量，提出了一种定量分析方法。基于三级（理想材料级、实际电极级和软包电池级）分析，除了锂金属外，高锂化锂镁（Li-Mg）合金也能够实现500 Wh/kg的锂硫电池。因此，本文对Li-Mg和其他锂基合金的研究进行了综述，以启发实现高能量密度和长循环锂硫电池的可行途径。
