The lithium-sulfur (Li-S) battery is a very promising candidate for the next generation of energy storage systems required for electrical vehicles and grid energy storage applications due to its very high theoretical specific energy (2500 W h kg⁻¹). However, low Coulombic efficiency (CE) during repeated Li metal plating/stripping has severely limited the practical application of rechargeable Li-S batteries. In this work, a new electrolyte system based on a high concentration of LiNO₃ in diglyme (G2) solvent is developed which enables an exceptionally high CE for Li metal plating/stripping and thus high stability of the Li anode in the sulfur-containing electrolyte. The tailoring of electrolyte properties for the Li anode has proven to be a highly successful strategy for improving the capacity retention and cycle life of Li-S batteries. This electrolyte provides a CE of greater than 99% for over 200 cycles of Li plating/stripping. In contrast, the Li anode cycles for less than 35 cycles (with a high CE) in the state-of-the-art 1 M LiTFSI + 0.3 M LiNO₃ in 1,3-dioxolane:1,2-dimethoxyethane (DOL:DME) electrolyte under the same conditions. The stable Li anode enabled by the new electrolyte may accelerate the applications of high energy density Li-S batteries in both electrical vehicles and large-scale grid energy storage markets.

锂硫（Li-S）电池具有极高的理论比能（2500 W h kg ^-1），是电动汽车和电网储能应用所需的下一代储能系统的非常有希望的候选者。然而，在重复的锂金属镀覆/剥离期间的低库仑效率（CE）严重限制了可再充电Li-S电池的实际应用。在这项工作中，基于高浓度LiNO ₃的新型电解质系统在二甘醇二甲醚（G2）中开发了一种溶剂，该溶剂可为锂金属镀覆/剥离提供极高的CE，从而使锂阳极在含硫电解质中具有很高的稳定性。事实证明，为Li阳极定制电解质性能是提高Li-S电池的容量保持率和循环寿命的非常成功的策略。该电解液在200多次Li电镀/剥离过程中提供的CE大于99％。相反，在最新的1 M LiTFSI + 0.3 M LiNO _3中，Li阳极循环少于35个循环（CE高）。在相同条件下在1,3-二氧戊环：1,2-二甲氧基乙烷（DOL：DME）电解质中溶解。由新电解质制成的稳定的Li阳极可加快高能量密度Li-S电池在电动汽车和大规模电网储能市场中的应用。