To enable next-generation high-energy-density lithium (Li)-metal batteries (LMBs), an electrolyte that has simultaneous high Li-metal Coulombic efficiency (CE) and high anodic stability on cathodes is of significant importance. Sulfones are known for strong resistance against oxidation, yet their application in LMBs is restricted because of their poor compatibility with Li-metal anodes, high viscosity, and poor wettability. Here, we demonstrate that a high Li CE over 98% can be achieved in concentrated sulfone-based electrolytes. Furthermore, the viscosity and wettability issues of sulfones are resolved by the addition of a fluorinated ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, to form a localized high-concentration electrolyte (LHCE), which not only provides further improvement in Li CE (98.8%) but also remains anodically stable with high-voltage cathodes, suppresses Al corrosion, and enables LMBs to operate in a wide temperature range. As a result, significantly improved cycling performance of LMBs has been realized with sulfone-based LHCE.

为了实现下一代高能量密度锂（Li）金属电池（LMBs），同时具有高锂金属库仑效率（CE）和高阴极阳极稳定性的电解质非常重要。众所周知，砜具有很强的抗氧化性，但由于它们与锂金属阳极的相容性差，粘度高和润湿性差，因此在LMB中的应用受到限制。在这里，我们证明了在浓缩砜基电解质中可以实现超过98％的高Li CE。此外，通过添加氟化醚1,1,2,2-四氟乙基-2,2,3,3-四氟丙基醚解决了砜的粘度和润湿性问题，从而形成了局部高浓度电解质（LHCE ），不仅可以进一步改善Li CE（98。8％），但在高压阴极上仍保持阳极稳定，可抑制Al腐蚀，并使LMB能够在较宽的温度范围内运行。结果，基于砜的LHCE已经实现了LMB的循环性能的显着改善。