Enhancing interface stability and ionic conductivity in the designed Na₃SbP_0.4xS_4-xO_x sulfide solid electrolyte...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• All-solid-state sodium batteries are promising for energy storage.
• Limited electrochemical stability and low ionic conductivity of solid electrolytes hinder their application, especially with sodium metal anodes.

Purpose of the Study:

• To investigate the impact of phosphorus (P) and oxygen (O) doping on the Na3SbS4 solid electrolyte.
• To improve the electrochemical stability and ionic conductivity of the solid electrolyte for sodium-ion batteries.

Main Methods:

• Structural characterization and electrochemical testing of modified Na3SbS4 electrolytes.
• Fabrication and testing of sodium/solid electrolyte/sodium symmetrical cells.

Main Results:

• The modified electrolyte Na3SbP0.16S3.6O0.4 demonstrated significantly improved electrochemical stability (260 h at 0.1 mA cm-2).
• Room temperature ionic conductivity reached 3.82 mS cm-1, comparable to commercial standards.
• Enhanced stability of the solid electrolyte interface was observed.

Conclusions:

• Doping Na3SbS4 with P and O elements is an effective strategy to enhance electrochemical stability and ionic conductivity.
• The improved solid electrolyte facilitates the development of high-energy-density, long-lifespan all-solid-state sodium-ion batteries.
• Solid electrolyte interface stability is crucial for all-solid-state sodium battery performance.