Epoxy Resin-Reinforced F-Assisted Na3Zr2Si2PO12 Solid Electrolyte for Solid-State Sodium Metal Batteries

Solid sodium ion batteries (SIBs) show a significant amount of potential for development as energy storage systems; therefore, there is an urgent need to explore an efficient solid electrolyte for SIBs. Na3Zr2Si2PO12 (NZSP) is regarded as one of the most potential solid-state electrolytes (SSE) for SIBs, with good thermal stability and mechanical properties. However, NZSP has low room temperature ionic conductivity and large interfacial impedance. F−doped NZSP has a larger grain size and density, which is beneficial for acquiring higher ionic conductivity, and the composite system prepared with epoxy can further improve density and inhibit Na dendrite growth. The composite system exhibits an outstanding Na+ conductivity of 0.67 mS cm−1 at room temperature and an ionic mobility number of 0.79. It also has a wider electrochemical stability window and cycling stability.