Battery recycling makes economic and environmental sense


4 Minute read

Lithium-ion batteries will help power a carbon-neutral future. As demand for lithium batteries skyrockets, University of Melbourne engineers are seeking to close the loop between battery manufacturers and recyclers.

The resources industry has developed technologies for extracting key minerals from their raw materials. Research at the Faculty of Engineering and Information Technology is working to extend these techniques for commercial lithium-ion battery recycling processes. Previously discarded metals like lithium, nickel and cobalt can be extracted by the adaptation of these technologies.

Our research has shown that with the right industry partner, the recycling process can be profitable.

Why demand for lithium-ion batteries is rising

Rechargeable lithium-ion batteries power the electronic devices that have become necessary for daily life, from laptops to smartphones.

But they’re also needed to reduce carbon emissions. Lithium-ion batteries power electric vehicles. Electricity generated by renewable sources is dependent on the weather, and batteries can also be used to stabilise our energy supply.

“Lithium batteries are arguably one of the most important technologies required to decarbonise the future society,” says graduate researcher Junnan Lu.

Why Australia should recycle lithium-ion batteries

"The aim of my research is to recycle all materials in the batteries to mitigate the negative environmental impact associated with the disposal of end-of-life batteries,” says Lu.

To make lithium-ion batteries, we need critical minerals like lithium, aluminium, cobalt and nickel. They are crucial to energy transition technologies but can be challenging to extract, with supplies often restricted geographically.

Only 10 per cent of lithium-ion batteries in Australia were recycled in 2021, likely due to low collection rates. As there is currently no national recycling scheme, the batteries are stored and forgotten or discarded. A 2018 report by CSIRO estimated that most lithium-ion batteries end up in landfill.

“This was very worrying to me because batteries can catch fire very quickly and they are harmful to the local ecosystem,” says Lu.

In failing to recycle these batteries, Australia is dumping potential resources of critical metals and polluting the environment. The economic and environmental cost of mining the raw materials needed for the batteries is also neglected.

“The resources industry can play a key role in decarbonisation. Technologies developed to extract critical components from mining can also be applied to recycling. As part of our Sustainable Resources platform, this research in reclaiming critical minerals will contribute to a greener resources sector,” says platform lead Associate Professor Kathryn Mumford.

Recycling lithium-ion batteries is technologically possible, socially responsible and economically viable. There is also growing political interest in battery recycling, with Australia’s government announcing a recycling, reuse and stewardship initiative for large-format batteries as part of its National Electric Vehicle Strategy (PDF, 7.93 MB).

Learn more about Sustainable Resources research

How lithium-ion batteries are recycled

The technologies needed for recycling lithium-ion batteries already exist in part.

“It's essentially urban mining,” says Lu.

Recycling begins with sorting different types of lithium-ion batteries and dismantling them by hand. This is often a labour-intensive and hazardous process that requires specialist knowledge.

Next the batteries are torn apart by comminution and shredding to reduce the particle size and expose the valuable materials.

Materials like copper, aluminium, iron and plastic can be separated by beneficiation. This is another resources industry process used to separate materials based on their physical properties like density and magnetism.

How our research extends battery recycling

Left over after these three steps is the battery’s black mass – a mixture of the battery’s anode and cathode, containing metal oxides, graphite and impurities.

While commercial battery recyclers generally stop here, Lu’s research at the University of Melbourne has extended the separation process to extract metals in the black mass: lithium, cobalt and nickel.

Leaching followed by liquid-liquid extraction can be used to target different metals in the black mass. These processes are already used in the resources industry for elements like uranium or the rare earth elements.

Currently, the best way to begin recycling materials in the black mass is to partner with university researchers like Lu. With the right partner, on the right scale, Lu’s research has found that the process can be profitable.

He is also seeking to work with other technical experts and researchers to explore technologies to recycle other materials in the batteries, such as the electrolyte and the separator materials.

“I’m looking forward to exploring collaborations with battery manufacturers and local battery recyclers in order to reduce the overall cost of recycling. This would have a direct impact on the cost of lithium-ion batteries and make the renewable energy more affordable,” says Lu.

Associate Professor Kathryn Mumford
+61 3 8344 0048

First published on 9 May 2023.

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