03:16 12-01-2026

Sodium–sulfur battery could reset cost, safety and power

Chinese researchers have unveiled a battery that could radically reshape the energy storage market. The design pairs sodium and sulfur and is positioned to surpass lithium-based rivals in energy density, safety, and affordability.

A chemistry breakthrough

The study conducted at Shanghai Jiao Tong University addresses the core weaknesses of conventional sodium–sulfur cells—low operating voltage and the need for excess sodium. Rather than the standard S/Na2S reaction, the team adopted a new S0/S4+ redox chemistry and dispensed with an active anode entirely. An aluminum current collector takes its place, while the cathode uses S8 sulfur.

Record figures and safety

In tandem with a nonflammable chloraluminate electrolyte, the prototype already delivers up to 1,198 W/kg in early tests. With a Bi‑COF catalyst, that figure rises to 2,021 W/kg—territory most contemporary batteries don’t reach. The electrolyte itself does not ignite, sharply reducing fire risk. On paper, those numbers would reset expectations for EV packs and stationary storage, though the lab bench is only the first hurdle.

Price and real-world constraints

The projected cost is about $5 per kWh, roughly an order of magnitude lower than lithium batteries. The caveats are substantial: the electrolyte is aggressive, difficult to manufacture, and has yet to prove long-term durability in real use. Until that endurance is shown, the promise looks compelling but calls for measured optimism.