Zhu Yu-Jie, Bi Chen-Xi, Zhao Meng, Li Zheng, Feng Wen-Jun, Sun Furong, Zhang Xue-Qiang, Li Bo-Quan, 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.
Adv Mater. 2025 Jul 1:e2506132. doi: 10.1002/adma.202506132.
Lithium-sulfur (Li-S) batteries are promising next-generation energy storage systems due to their ultrahigh theoretical energy density of 2600 Wh kg. However, soluble lithium polysulfides (LiPSs) violently corrode Li metal anodes, inducing rapid capacity decay and poor cycling lifespan of Li-S batteries. Herein, the corrosion of different LiPS species on the Li metal anode is systematically investigated. The corrosion rate of Li metal anode by LiS and LiS is higher than LiS. The discrepancy in corrosion rate is attributed to the continuous reaction between the LiPSs and Li metal, while the corrosion can hardly be prohibited by the LiPS-generated solid electrolyte interphase. Smaller Li nuclei size, more uniform Li deposition, and more durable cycling of Li metal anodes are found in LiS electrolyte in comparison with LiS and LiS electrolytes. Consequently, a LiPS selection strategy is proposed to selectively inhibit the corrosion of high-order LiPSs and successfully prolong the cumulative capacity by 31% in Li-S batteries. This work clarifies the fundamentals of Li metal anode corrosion by different LiPS species and highlights the rational selection of favorable LiPS species for promoting the cycling durability of Li-S batteries.
锂硫（Li-S）电池因其2600 Wh kg的超高理论能量密度而成为很有前景的下一代储能系统。然而，可溶性多硫化锂（LiPSs）会剧烈腐蚀锂金属阳极，导致锂硫电池快速的容量衰减和较差的循环寿命。在此，系统研究了不同种类的LiPSs对锂金属阳极的腐蚀情况。Li₂S₄和Li₂S₆对锂金属阳极的腐蚀速率高于Li₂S₂。腐蚀速率的差异归因于LiPSs与锂金属之间的持续反应，而由LiPSs生成的固体电解质界面几乎无法阻止这种腐蚀。与Li₂S₂和Li₂S₆电解质相比，在Li₂S₄电解质中发现锂金属阳极的锂核尺寸更小、锂沉积更均匀且循环更持久。因此，提出了一种LiPSs选择策略，以选择性地抑制高阶LiPSs的腐蚀，并成功地使锂硫电池的累积容量提高了31%。这项工作阐明了不同种类的LiPSs对锂金属阳极腐蚀的基本原理，并强调了合理选择有利的LiPSs种类对提高锂硫电池循环耐久性的重要性。
