Salt bath gives battery boost
Australian researchers have found a way to squeeze more out of rechargeable lithium batteries.
CSIRO scientists, in collaboration with RMIT University and QUT, have demonstrated that pre-treating a battery’s lithium metal electrodes with an electrolyte salt solution extends the battery life and increases performance and safety.
The simple method could accelerate the development of next-gen energy storage solutions and overcome the issue of ‘battery range anxiety’ that is currently a barrier in the electric car industry.
CSIRO battery researcher Dr Adam Best said the pre-treated lithium metal electrodes could potentially outperform other batteries currently on the market.
“Our research has shown by pre-treating lithium metal electrodes, we can create batteries with charge efficiency that greatly exceeds standard lithium batteries,” Dr Best said.
The pre-treatment 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.
Ionic liquids - room temperature molten salts - are a unique class of material that are clear, colourless, odourless solutions and are non-flammable.
When used in batteries these materials, they can prevent the risk of fire and explosion.
The salt bath pre-treatment adds a protective film onto the surface of the electrode that helps stabilise the battery when in operation.
“The pre-treatment reduces the breakdown of electrolytes during operation, which is what determines the battery’s increased performance and lifetime,” Dr Best said.
Batteries that have undergone the process can also spend up to one year on the shelf without loss of performance.
QUT researcher Assoc. Prof. Anthony O’Mullane said the method can be easily adopted by manufacturers.
“The pre-treatment process is readily transferrable to existing manufacturing processes,” Assoc. Prof. O’Mullane said.
The electrolyte salt solutions, to which CSIRO holds patents, come in a range of chemical compositions.
The team has been put together to develop batteries based on this technology, and are looking for partners to help bring these materials and devices to market.