High performance sodium-sulfur batteries at low temperature enabled by superior molten Na wettability

Reducing the operating temperature of conventional molten sodium–sulfur batteries (∼350 °C) is critical to create safe and cost-effective large-scale storage devices. By raising the surface treatment temperature of lead acetate trihydrate, the sodium wettability on β′′-Al2O3 improved significantly at 120 °C. The low temperature Na–S cell can reach a capacity as high as 520.2 mA h g−1 and stable cycling over 1000 cycles.