Low temperature and rapid microwave sintering of Na3Zr2Si2PO12 solid electrolytes for Na-Ion batteries

Abstract

In this work, the synthesis of Na3Zr2Si2PO12 (NZSP) solid electrolytes is demonstrated through a low temperature and rapid microwave sintering process and its application in Na-ion batteries is investigated. The quickly and uniformly heating of microwave sintering can inhibit the excessive grain growth significantly, resulting in the fine grained NZSP electrolyte with high relative density of 96%. The obtained NZSP electrolyte sintered by microwave heating at 850 °C for 30 min shows high room temperature ionic conductivity of 2.511 × 10−4 S cm−1, which is comparable to that of sample synthesized by solid-state sintering method at 1200 °C for 720 min. The application of the resultant NZSP electrolyte in Na-ions batteries is evaluated by assembling Na3V2(PO4)3/C|NZSP|Na solid sodium battery. Discharge specific capacity of 75.7 mAh g−1 with a capacity retention rate of 81.97% is recorded after 100 cycles at 0.5C. This work reports the microwave sintering synthesis of NZSP solid electrolyte with fascinating advantages of energy-saving and time-saving, driving the application of inorganic solid electrolyte in solid batteries.