硫化物固态电解质Li6PS5Cl的球磨-固相烧结制备与性能

硫银锗矿结构的硫化物固态电解质Li₆PS₅Cl（LPSC）具有离子电导率高（>3×10^-3 S·cm^-1）和对锂稳定性良好等特点，是构建全固态锂离子电池的理想电解质材料之一，具有良好的发展前景。本工作采用高能球磨和惰性气氛固相烧结相结合的方法制备硫银锗矿型固态电解质LPSC，并采用粉末X射线衍射（XRD）、拉曼光谱（Raman spectra）和扫描电子显微镜（SEM）等对其进行表征，探究制备工艺对LPSC结构、成分和电学性质等的影响。结果表明：高能球磨会破坏原料的晶粒，降低晶粒尺寸，延长球磨时间有利于LPSC前驱体粉末的非晶化和后续烧结，提高烧结温度将促进制备的LPSC电解质的物相变纯和离子电导率升高，但烧结温度过高会导致LPSC的分解。综合考虑球磨时间和烧结温度对材料离子电导率和电子电导率的影响，经8 h球磨和500℃烧结制备的LPSC在室温下具有最高的离/电子电导率比（2.091×10⁵），其离子电导率高达4.049×10^-3 S·cm^-1，而电子电导率仅为1.936×10^-8 S·cm^-1。利用该电解质制备的712 NCM/LPSC/In-Li全固态电池在0.1 C的充放电倍率下首周放电比容量高达151.3 mAh·g^-1，且具有优良的循环稳定性。

Preparation and properties of sulfide solid state electrolyte Li6PS5Cl by ball milling-solid phase sintering

Li₆PS₅Cl(LPSC),a sulfide solid-state electrolyte with an argyrodite structure,is one of the ideal electrolyte materials for the construction of all-solid-state lithium-ion batteries.It has good development prospects because of its high ionic conductivity(>3×10^-3S·cm^-1)and good stability to lithium.In this work,LPSC was prepared by the combination of high-energy ball milling and inert atmosphere solid-phase sintering,and powder X-ray diffraction,Raman spectra,and scanning electron microscopy were used to investigate the effects of the preparation process on the structure,composition,electrical properties,and ion conductivity of LPSC.The results show that the extended ball milling time is beneficial to the amorphization and subsequent sintering of the LPSC precursor powder.The increase of the sintering temperature will promote the physical purity and electrical conductivity of the prepared LPSC electrolyte,but the high sintering temperature will lead to the decomposition of LPSC.The LPSC prepared by 8 h ball milling and 500℃sintering has the highest ion/electron conductivity ratio(2.091×10⁵)at room temperature,with ionic conductivity up to 4.049×10^-3 S·cm^-1 and electronic conductivity only 1.936×10^-8 S·cm^-1.The 712 NCM/LPSC/In-Li all-solid-state battery prepared with this electrolyte has a first-turn discharge specific capacity of 151.3 mAh·g^-1 at a charge/discharge ratio of 0.1 C,and has excellent cycling stability.