All‐Solid‐State Sodium Batteries with a Polyethylene Glycol Diacrylate–Na3Zr2Si2PO12 Composite Electrolyte. Issue 1 (10th December 2020) - Yu, Xingwen
Abstract : A novel sodium‐ion conducting polymer–ceramic solid‐state composite electrolyte is developed for ambient‐temperature sodium batteries. Polyethylene glycol diacrylate (PEGDA) is used as a polymeric matrix into which ceramic nanoparticles of NASICON‐type Na3 Zr2 Si2 PO12 are integrated. The PEGDA polymeric phase of the composite can maintain an amiable ionic interface between the solid‐state electrolyte and electrodes. The Na3 Zr2 Si2 PO12 ceramic phase not only enhances the sodium‐ion conductivity of the composite but also can suppress the Na dendrites from penetrating through the electrolyte membrane. To optimize the Na + ‐ion conductivity, a succinonitrile (SCN) plasticizer is also incorporated. The composite solid electrolyte membranes are fabricated with an ultraviolet (UV) curing process. Through proper management of the composition, the PEGDA‐SCN‐Na3 Zr2 Si2 PO12 ‐NaClO4 composite solid electrolyte delivers an ionic conductivity of 4.5 × 10 −4 S cm −1 at room temperature. All‐solid‐state Na cells with the PEGDA‐SCN‐NaClO4 ‐Na3 Zr2 Si2 PO12 composite electrolyte are fabricated by coupling a Na2 MnFe(CN)6 positive electrode to a Na‐metal negative electrode. The resulting Na ‖ PEGDA‐SCN‐NaClO4 ‐Na3 Zr2 Si2 PO12 ‖ Na2 MnFe(CN)6 cells show remarkable cycling stability. Abstract : A rationally designed polymer–ceramic composite electrolyte comprising a polyethylene glycol diacrylate (PEGDA) matrix, a succinonitrile (SCN) plasticizer, a Na3 Zr2 Si2 PO12 ceramic filler, and a NaClO4 salt provides a reasonably high Na + ‐ion conductivity, dendrite‐suppression capability, and a broad electrochemical stability window. The PEGDA‐SCN‐NaClO4 ‐Na3 Zr2 Si2 PO12 composite enables the operation of ambient‐temperature all‐solid‐state sodium batteries with remarkably stable cycling performance.