The quest to replace petrol and diesel cars has been focused heavily on the development of lithium batteries to fuel the electric car industry, but scientists have said a new compound made of sea salt could offer far greater storage capacity.
Researchers at the University of Sydney have developed a prototype battery that uses sodium-sulphur – which can be processed from sea water – with four times the battery life at a fraction of the cost of lithium production.
Sodium batteries have been around for decades but have been limited by low energy capacity and short life cycles. However, the team led by Dr Shenlong Zhao at the School of Chemical and Biomolecular Engineering has managed to create batteries with more capacity using a pyrolisis processing technique and carbon-based electrodes.
This made the sulphur more reactive and improved the reversibility of reactions between sulphur and sodium.
If the battery can be scaled up to become a viable option for motor vehicles and other electrical appliances, chemical plants may be increasingly involved in the contract processing work required to make these more effective sea salt batteries.
Dr Zhao commented: “Storage solutions that are manufactured using plentiful resources like sodium – which can be processed from sea water – also have the potential to guarantee greater energy security more broadly.” He added that this would enable more countries to decarbonise quickly and easily.
If the technology can be extrapolated successfully, this could limit the role of lithium just as the processing of the material is becoming a major growth industry in the UK.
The last few weeks have seen the granting of planning permission for the first two lithium refining plants in the UK, owned by Tees Valley Lithium and Green Lithium respectively. Both will be based at the Tees Freeport and are scheduled to start operating in 2025.