锂硫电池因其超高的理论能量密度有望替代传统的锂离子电池。但现有锂硫电池电解液/硫（E/S）比率较高，造成其实际能量密度远低于理论值。提高正极氧化还原中间体聚硫化锂（Li2Sx）在电解液中的溶解度，是提高正极S利用率、并显著降低E/S比的有效途径。本项目提出利用多价金属离子添加剂活化溶剂分子中受体H，进而大幅提升Li2Sx溶解度的新思路。（1）研究多价金属离子在不同链长醚溶剂中的溶剂化结构，分析其对受体H的活化规律；进而研究受体H与Li2Sx的相互作用，揭示受体H的活化度对Li2Sx溶解度的影响规律；（2）在此基础上，考察多价金属盐的阴离子与溶剂中受体H的相互作用以及其与Sx2-间的竞争关系。通过上述研究，解析多价金属离子通过活化溶剂分子中受体H进而提高Li2Sx溶解度的作用规律，阐明不同阴离子配位对多价金属离子促进Li2Sx溶解的影响规律，为发展低E/S比的锂硫电池提供理论依据和技术手段。

Lithium sulfur battery is expected to replace the traditional lithium-ion battery due to its high theoretical energy density. However, the ratio of electrolyte/sulfur (E/S) in the existing lithium sulfur battery is relatively high, which makes the actual energy density much lower than the theoretical value. Improving the solubility of Li2Sx (the intermediate product of S redox) in electrolyte is an effective way to improve the utilization of S and reduce the E/S ratio. In this project, a new idea is proposed to activate the receptor H in solvent molecules by using polyvalent metal ion additives, so as to greatly improve the solubility of Li2Sx. (1) To study the solvation structure of polyvalent metal ions in different chain length ether solvents, and analyze the activation rule of receptor H; then study the interaction between receptor H and Li2Sx, and reveal the influence of the activation degree of the receptor H on the solubility of Li2Sx; (2) On the base of above study, to analyze the interaction between the anions of polyvalent metal salts and receptor H in solvents and the competition relationship between these anions and Sx2-. Through the above research, the law of polyvalent metal ions improving the solubility of Li2Sx by activating the acceptor H in the solvent molecule will be analyzed, and the influence of different anion coordination on the dissolution of Li2Sx promoted by polyvalent metal ions will be clarified, which can provide theoretical basis and technical means for the development of low E/S ratio lithium sulfur batteries.