Low-cost, high-capacity sodium-sulphur battery expected to be gamechanger for clean energy economy

Staff Writer | December 8, 2022 | 

The authors say that storage solutions for clean energy generators can be manufactured using plentiful resources like sodium – which can be processed from seawater. (Reference image by 掬茶, Wikimedia Commons.)

An international team of researchers is hoping that a new, low-cost battery which holds four times the energy capacity of lithium-ion batteries and is far cheaper to produce will significantly reduce the cost of transitioning to a decarbonized economy.


In a paper published in the journal Advanced Materials, the scientists explain that the battery has been made using sodium-sulphur – a type of molten salt that can be processed from seawater – which costs much less to produce than lithium-ion.

Although sodium-sulphur (Na-S) batteries have existed for more than half a century, they have been an inferior alternative and their widespread use has been limited by low energy capacity and short life cycles.

But using a simple pyrolysis process and carbon-based electrodes to improve the reactivity of sulphur and the reversibility of reactions between sulphur and sodium, the researchers’ battery has shaken off its formerly sluggish reputation, exhibiting super-high capacity and ultra-long life at room temperature.

The team says the Na-S battery is also a more energy-dense and less toxic alternative to lithium-ion batteries which, while used extensively in electronic devices and for energy storage, are expensive to manufacture and recycle.

“Our sodium battery has the potential to dramatically reduce costs while providing four times as much storage capacity. This is a significant breakthrough for renewable energy development which, although it reduces costs in the long term, has had several financial barriers to entry,” lead researcher Shenlong Zhao, from the University of Sydney, said in a media statement. “When the sun isn’t shining and the breeze isn’t blowing, we need high-quality storage solutions that don’t cost the earth and are easily accessible on a local or regional level.”

According to Zhao, he and his team hope that by providing a technology that reduces costs, the clean energy economy gets closer to becoming a reality.

“It probably goes without saying but the faster we can decarbonize — the better chances we have of capping warming,” the scientist said. “Storage solutions that are manufactured using plentiful resources like sodium – which can be processed from seawater – also have the potential to guarantee greater energy security more broadly and allow more countries to join the shift towards decarbonization.”