Arising from the general formula Li 7 PS 6 , argyrodite materials display a transition from a normal to a superionic phase from orthorhombic to a cubic phase. However, their RT ionic conductivity remains relatively low, with values around 1.6 ×10 -6 S cm -1 . The high-conducting phase can be stabilized by introducing compositions such as Li 6 PS 5 X (where X represents a halogen atom like Cl, Br, I, or a vacancy). The crystal structure of argyrodite materials at the superionic phase is cubic, featuring the space group F 43m. Within this structure, Li ions occupy 24g and 48h sites, S atoms are found in 4a and 4c sites, P atoms are situated in 4b sites, and either halide atoms (X) or vacancies occupy 4a sites. Specifically, the S atoms in 4a sites form PS 4 tetrahedra with P atoms in 4b sites, while the S atoms in 4c sites bridge between PS 4 tetrahedra (as depicted in Fig. )) . The Li ions are distributed in octahedral coordination around the S atoms. The presence of various interstitial sites surrounding the halide ions facilitates high ionic conductivity (Fig. (f)), typically within the range of 10 -2 to 10 -3 S cm -1 at RT, with low activation energies typically around 0.2 to 0.3 eV .