Synthesis and electrochemical performance of (100-x)Li7P3S11-xLi2OHBr composite solid electrolyte for all-solid-state lithium batteries

LiPSsolid electrolytes with high lithium-ion conductivity are promising candidates for use in all-solidstate lithium batteries.However,this electrolyte’s poor interfacial compatibility with lithium electrodes causes unstable cyclability.In this study,in order to address this problem,(100-x)LiPS-xLiOHBr(x=0,2,5,10,20,30,40,and 50)electrolytes are prepared by a high energy ball-milling technique and heat-treatment process.The resulting(100-x)LiPS-xLiOHBr(x=2,5,10,20,30,40,and 50)electrolytes provide improved electrochemical performance with good cycling stability and a wide electrochemical window of up to 10 V(vs.Li/Li~+).Moreover,these electrolytes have high ionic conductivity of 10–10S/cm at room temperature.Particularly,the 90LiPS-10LiOHBr electrolyte displays the highest conductivity of 4.4×10S/cm at room temperature as well as improved cyclability.Moreover,90LiPS-10LiOHBr shows decreased interfacial resistance between the solid electrolyte and cathode electrode,which was revealed by Electrochemical Impedance Spectroscopy(EIS)analysis.The initial discharge capacity of 90LiPS-10LiOHBr was found to be 135 m Ah/g when used in a In|solid electrolyte|Li(NiCoMn)Oall-solid-state lithium battery(ASSLB).Thus,we can conclude the addition of LiOHBr into the LiPSresults in enhanced electrochemical properties.