We report an electrolyte with low flammability, based on diethylene glycol dimethyl ether (DEGDME) dissolving lithium bis-trifluoromethane sulfonimidate (LiTFSI), and lithium nitrate (LiNO₃) for high-performances lithium/sulfur battery. Self-diffusion coefficients, conductivity, and lithium transport number of the electrolyte are obtained by nuclear magnetic resonance and electrochemical impedance spectroscopy. Interface stability, lithium stripping/deposition ability, and the electrochemical stability window of the electrolyte are determined by voltammetry and impedance spectroscopy. The tests suggest conductivity higher than 10⁻² S cm⁻¹, lithium transport number of about 0.5, electrochemical stability extending from 0 V to 4.6 V, and excellent compatibility with lithium metal. A composite cathode using sulfur and multi walled carbon nanotubes (MWCNTs) is characterized in terms of structure and morphology by X-ray diffraction and scanning electron microscopy. The study shows spherical flakes in which the carbon nanotubes protect the crystalline sulfur from excessive dissolution, and create the optimal host for allowing the proper cell operation. The Li/S cell reveals highly reversible process during charge/discharge cycles, fast kinetic, and lithium diffusion coefficient in the sulfur electrode ranging from 10⁻¹² to 10⁻¹⁰ cm² s⁻¹. The cell evidences a coulombic efficiency approaching 100%, capacity from 1300 mAh g⁻¹ to 900 mAh g⁻¹ and practical energy density higher than 400 Wh kg⁻¹.

我们报告了一种基于二甘醇二甲醚（DEGDME）溶解双三氟甲烷磺酰亚胺锂（LiTFSI）和硝酸锂（LiNO ₃）的低可燃性电解质，用于高性能锂/硫电池。通过核磁共振和电化学阻抗谱获得电解质的自扩散系数，电导率和锂的迁移数。界面稳定性，锂的剥离/沉积能力以及电解质的电化学稳定性窗口是通过伏安法和阻抗谱法确定的。测试表明电导率高于10 ^-2  S cm ^-1，锂的传输数约为0.5，电化学稳定性从0 V扩展至4.6 V，并且与锂金属的相容性极佳。使用硫和多壁碳纳米管（MWCNT）的复合阴极通过X射线衍射和扫描电子显微镜在结构和形态方面进行了表征。研究表明，球形薄片中的碳纳米管可以保护结晶硫免于过度溶解，并为允许适当的电池运行创造了最佳基质。Li / S电池在充放电循环中显示出高度可逆的过程，快速的动力学特性以及锂在硫电极中的扩散系数为10 ^-12至10 ^-10  cm ²  s ^-1。该电池证明库仑效率接近100％，容量从1300 mAh g ^-1到900 mAh g ^-1，实用能量密度高于400 Wh kg ^-1。