Salt baths boost electric car batteries

Australian scientists have demonstrated that pretreating a battery’s lithium metal electrodes with an electrolyte salt solution extends the battery life and increases performance and safety. The pretreatment adds a protective film onto the surface of the electrode that helps stabilise the battery when in operation.

Developed by CSIRO scientists in collaboration with RMIT University and QUT, the pretreatment process involves the immersion of lithium metal electrodes in an electrolyte bath containing a mixture of ionic liquids and lithium salts prior to a battery being assembled. These materials can prevent the risk of fire and explosion, a known rechargeable battery issue.

“The pretreatment reduces the breakdown of electrolytes during operation, which is what determines the battery’s increased performance and lifetime,” said CSIRO battery researcher Dr Adam Best. Batteries that have undergone the process can also spend up to one year on the shelf without loss of performance.

Dr Best suggested that the pretreated lithium metal electrodes could potentially outperform other batteries currently on the market, noting that his team can “create batteries with charge efficiency that greatly exceeds standard lithium batteries”.

The method also bodes well for the development of next-gen energy storage solutions and overcoming the issue of ‘battery range anxiety’ in the electric car industry. It is believed that the technology has the potential to improve electric vehicle drive range and battery charge to a point where electric vehicles will soon be competitive with traditional petrol vehicles.

The process has been published in the journal Nature Communications and is readily transferrable to manufacturing processes, according to QUT researcher Associate Professor Anthony O’Mullane from QUT. The electrolyte salt solutions come in a range of chemical compositions.