Preparations and Properties of Low Cost Sulfide Solid Electrolytes Li6-xPS5-xClx
- 2020年第26卷 
硫化物固体电解质以其室温电导率高,热稳定性好,电化学窗口宽等特点,在高功率及室温固态电池方面优势突出,是极具潜力的固态电解质材料. 但制备其所需的高纯度Li2S原料高昂的价格使其实际应用受到掣肘,故本文使用单质锂金属（99.9%）、升华硫、氯化锂和五硫化二磷等低成本原料,采用球磨法和高温热处理制备得到了Li6-xPS5-xClx（x = 0.5）固态电解质粉末,通过X射线衍射（XRD）、拉曼（Raman）、扫描电子显微镜（SEM）及能谱仪（EDS）对Li6-xPS5-xClx（x = 0.5）固态电解质进行了表征,并使用交流阻抗法测试了其电导率,电导率可达8.29×10 -4 S·cm -1,将Li6-xPS5-xClx（x = 0.5）固态电解质粉末进行冷压制片,制成Li对Li半电池后显示了良好的循环性能.With the shortage of energy and environmental pollution, the storage of electric energy is getting more attention all over the world. In order to improve the energy density and safety performance of batteries, uses of solid electrolyte become more and more popular. However, because the conductivity of solid electrolyte is not comparable to that of liquid electrolyte, the solid electrolyte application has certain limitations. With the efforts of researchers from various countries, there are several different solid electrolytes having better conductivity, for instance, sulfide solid electrolyte and oxide solid electrolyte. Sulfide solid electrolyte is a highly promising solid electrolyte material because of its high room temperature conductivity, good thermal stability and wide electrochemical window. It has outstanding advantages in high power and normal temperature solid state batteries. However, the application of expensive Li2S raw materials required high-purity has been hampered. In this paper, Li6-xPS5-xClx (x = 0.5) solid electrolyte was prepared by ball milling using low-cost raw materials such as elemental lithium metal (99.9%), sublimed sulfur (CP), P2S5 (AR) and LiCl (AR). The as-prepared Li6-xPS5-xClx solid electrolyte powder was characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and the cold-pressed Li6-xPS5-xClx tablets were tested for cycle performance and electrical conductivity in Li6-xPS5-xClx/Li half-cell. The results showed that through the pressure-free sintering at 550 oC, the total lithium-ion conductivity of the solid electrolyte at room temperature was 8.29×10 -4 S·cm -1, making commercialization of solid-state batteries possible.