improved ionic conductivity by synthesizing glass-ceramics via partial crystallization of sulfide glasses used as solid electrolyte materials. By optimizing crystallization time and heat treatment temperature, they controlled the crystallinity, achieving an optimized material with an ionic conductivity (1.33 × 10 -3 S/cm) 1.8 times greater than that (7.4 × 10 -4 S/cm) of glass with the same composition. These studies demonstrate that the properties of glass-ceramic materials are significantly influenced by the amount and morphology of crystals within the glassy phases. The crystalline particles precipitated in the bulk glass inherently form interfaces with the glass phase.