Ultrastable All-Solid-State Sodium Rechargeable Batteries

Abstract

The\ninsufficient ionic conductivity of oxide-based solid electrolytes\nand the large interfacial resistance between the cathode material\nand the solid electrolyte severely limit the performance of room-temperature\nall-solid-state sodium rechargeable batteries. A NASICON solid electrolyte\nNa_3.4Zr_1.9Zn_0.1Si_2.2P_0.8O₁₂, with superior room-temperature conductivity\nof 5.27 × 10^–3 S cm^–1, is\nachieved by simultaneous substitution of Zr⁴⁺ by aliovalent\nZn²⁺ and P⁵⁺ by Si⁴⁺ in Na₃Zr₂Si₂PO₁₂. The bulk conductivity\nand grain boundary conductivity of Na_3.4Zr_1.9Zn_0.1Si_2.2P_0.8O₁₂ are\nnearly 20 times and almost 50 times greater than those of pristine\nNa₃Zr₂Si₂PO₁₂, respectively.\nThe FeS₂||polydopamine-Na_3.4Zr_1.9Zn_0.1Si_2.2P_0.8O₁₂||Na\nall-solid-state sodium batteries, with a polydopamine modification\nthin layer between the solid electrolyte and the cathode, maintain\na high reversible capacity of 236.5 mAh g^–1 at a\n0.1 C rate for 100 cycles and a capacity of 133.1 mAh g^–1 at 0.5 C for 300 cycles, demonstrating high performance for all-solid-state\nsodium batteries.