Na3Zr2Si2PO12 Solid Electrolyte Separator for Aqueous Sodium-Ion Batteries: Synthesis via the One-Step Sintering of Glass-Ceramics

A dense Na₃Zr₂Si₂PO₁₂ (NZSP) solid electrolyte suitable for aqueous sodium-ion secondary batteries was synthesized using a glass-ceramic composite. The sintering process at temperatures ranging from 1050 to 1150 °C achieved a higher density at lower temperatures than sintering NZSP alone. This temperature range also allowed for greater density consistency. The ionic conductivity of the solid electrolyte was measured to be in the order of 1 mS/cm. Upon testing for water leakage, the electrolyte demonstrated sufficient density. Moreover, batteries employing this solid electrolyte achieved a stable voltage of 2 V and exhibited robust cycle performance, enduring over 100 cycles with good stability.