Na3NH2B12H12 as high performance solid electrolyte for all-solid-state Na-ion batteries
Abstract
Solid electrolyte with stable and fast Na+ ionic conductivity is of central importance in the development of all-solid-state sodium batteries. Here we present a novel Na+ conductor based on complex hydrides with composition of Na3NH2B12H12. It exhibits remarkable thermal stability up to 593 K and excellent electrochemical stable window up to 10 V (vs. Na+/Na). It demonstrates a high Na+ conductivity of 1.0 × 10-4 S cm-1 at a temperature of 372 K, which is much higher than those of its precursors NaNH2 and Na2B12H12. All-solid-state Na-ion batteries were constructed by employing the obtained Na3NH2B12H12 as electrolyte, TiS2 as cathode and sodium foil as anode, which can reversibly discharge/charge for over 200 cycles with more than 50% capacity retention at temperature of 353 K and a rate of 0.1 C. This work opens the gate to develop advanced solid electrolytes via combination of metal amides with closo borates.
- Publication:
-
Journal of Power Sources
- Pub Date:
- August 2018
- DOI:
- 10.1016/j.jpowsour.2018.06.054
- Bibcode:
- 2018JPS...396..574H
- Keywords:
-
- Na<SUB>3</SUB>NH<SUB>2</SUB>B<SUB>12</SUB>H<SUB>12</SUB>;
- Solid electrolyte;
- All-solid-state;
- Na-ion battery;
- Complex hydride