Designed anion and cation co-doped Na3Sb(WM)xS4 (M = Cl, Br, I) sulfide electrolytes with an improved conductivity and stable interfacial qualities

Abstract

The fabrication of all electrolytes from noncombustible ceramic materials offers a superior option for providing safer and higher-capacity batteries to fulfill future energy needs. To achieve a competitive performance with combustible liquid electrolytes used in commercial Li-ion batteries, the creation of ceramic material compositions with a high electrical conductivity is necessary. Here, we report that co-doping with W and halogens results in a superconductivity of 13.78 mS cm⁻¹ in a cubic-phase Na₃SbS₄ glass ceramic electrolyte. After undergoing high-temperature heat treatments, the W ions in the electrolyte can facilitate the replacement of S atoms with halogens, introducing many Na vacancies. The samples also had a high degree of cycling stability. An excellent glass ceramic electrolyte for Na ion batteries will be constructed for Na₃SbW_0.25Cl_0.25S₄.