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Title: An electrochemically stable homogeneous glassy electrolyte formed at room temperature for all-solid-state sodium batteries
Abstract All-solid-state sodium batteries (ASSSBs) are promising candidates for grid-scale energy storage. However, there are no commercialized ASSSBs yet, in part due to the lack of a low-cost, simple-to-fabricate solid electrolyte (SE) with electrochemical stability towards Na metal. In this work, we report a family of oxysulfide glass SEs (Na 3 PS 4− x O x , where 0 <  x  ≤ 0.60) that not only exhibit the highest critical current density among all Na-ion conducting sulfide-based SEs, but also enable high-performance ambient-temperature sodium-sulfur batteries. By forming bridging oxygen units, the Na 3 PS 4− x O x SEs undergo pressure-induced sintering at room temperature, resulting in a fully homogeneous glass structure with robust mechanical properties. Furthermore, the self-passivating solid electrolyte interphase at the Na|SE interface is critical for interface stabilization and reversible Na plating and stripping. The new structural and compositional design strategies presented here provide a new paradigm in the development of safe, low-cost, energy-dense, and long-lifetime ASSSBs.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
2117445
Publication Date:
NSF-PAR ID:
10396368
Journal Name:
Nature Communications
Volume:
13
Issue:
1
ISSN:
2041-1723
Sponsoring Org:
National Science Foundation
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