The improvement of electrochemical performance by mixing InF3 in Li5.3PS4.3Cl1.7 solid electrolyte.

All-solid-state batteries (ASSBs) employing solid electrolytes (SE) are currently gaining attention as next-generation energy storage devices. Solid electrolytes exhibit higher energy densities and operation across a wide temperature range than liquid electrolytes. The solid electrolyte acts as a separator, providing higher mechanical strength than polymer separators. This helps prevent cell deterioration and short circuit issues caused by lithium dendrite growth during charge – discharge cycles. Consequently, lithium metal, previously challenging to apply in conventional lithium-ion batteries, can be utilized as an anode electrode material. Sulfide-based solid electrolytes offer advantageous mechanical properties and high ionic conductivity. However, their narrow chemical/electrochemical stability window poses challenges. During the charging-discharging process of a battery with a lithium metal anode, a reduction decomposition reaction of the solid electrolyte occurs. On the other hand, Lithium Fluoride (LiF) exhibits low electronic conductivity due to a wide band gap but has a broad electrochemical stability window. In this study, we prepared a mixture of Li 5.3 PS 4.3 Cl 1.7 with InF 3 to generate an artificial solid electrolyte interphase (SEI) containing LiF. We confirmed the structural properties using powder X-ray diffraction (XRD). The XRD pattern showed the maintenance of the argyrodite structure, with only an increase in the peak intensity corresponding to InF 3. The optimized solid electrolyte-based ASSB demonstrated a higher initial discharge capacity of 172.8 mAh/g, a coulombic efficiency of 78.54 %, and a capacity retention rate of 93.6 %, outperforming ASSBs based on the bare solid electrolyte (Li 5.3 PS 4.3 Cl 1.7). • Li 5.3 PS 4.3 Cl 1.7 is synthesized through high energy dry ball-milling. • Li 5.3 PS 4.3 Cl 1.7 and InF 3 are mixed through simple hand grinding. • The optimized solid electrolyte has an ionic conductivity of 5.46mS/cm at RT. • The all-solid-state battery show a higher specific capacity of 172.8 mAh/g. • The all-solid-state battery shows a higher capacity retention of 93.58 %. [ABSTRACT FROM AUTHOR]