Wider approach needed to mitigate rising rechargeable battery emissions

Key Facts:

• A University of Melbourne-led study has found that demand for lithium-ion batteries (LIBs) could rise twentyfold by 2050, leading to an increase in supply-chain greenhouse gas emissions
• Published in *One Earth*, the research found that cleaner production methods, such as switching battery chemistries, greening factories and recycling materials, are insufficient to mitigate the predicted emissions increases.
• The study examined demand-side decarbonisation strategies alongside supply-side efforts, finding that combining both approaches could roughly halve total LIB supply-chain emissions roughly in half by 2050.

A new University of Melbourne-led study has identified new insights and evidence that could help significantly mitigate the fast-rising climate impact of Lithium-ion Batteries (LIBs).

Electric vehicle batteries are crucial to clean energy, but production emissions are significant. Most LIB decarbonisation research has focused on reducing emissions from the supply chain, including sourcing and refining raw materials, manufacturing and end-of-life recycling.

The study’s modelling found that by 2050, demand for LIBs used in electric cars, vans, buses, trucks and battery energy storage systems could rise twentyfold, leading to a tenfold increase in their supply-chain greenhouse gas emissions. The research also identified ways to reduce global LIB emissions on par to the annual emissions of the EU.

Published in Cell Press’ flagship sustainability journal ‘One Earth’, the research, led by University of Melbourne Associate Professor Wen Li, found that cleaner production alone was not enough to mitigate the resulting annual LIB supply chain emissions.

“Encompassing demand-side decarbonisation strategies, such as reducing battery sizes, extending battery lifetimes and promoting shared mobility, could help reduce the predicted global carbon dioxide (CO₂)-equivalent LIB emissions over that period to 2050 by around half,” said Associate Professor Li, from the Faculty of Engineering and Information Technology.

The study, with researchers from the Chinese Academy of Sciences and the University of Sheffield, was one of the first detailed global assessments to examine both supply-side and demand-side factors.

It was the first to examine several demand-side strategies for reducing impact on the global LIB supply chain and directly compare these contributions with ambitious supply-side decarbonisation efforts that could be introduced over time.

The global supply chain modelling covered battery material production, component production, battery manufacturing, and end-of-life treatment from 2024 through to 2050.

On the supply-side, cleaner production, such as switching battery chemistries, greener factories and recovering materials from used batteries, was essential, but not enough to mitigate predicted emissions increases over that time.

On the demand side, through battery technology advancement and business model innovation, researchers modelled how many batteries will be needed, what size, their longevity and replacement need, through to 2050. If mitigated, all four factors could help reduce the number of new batteries needed significantly around the globe for transport and energy storage.

Corresponding author Associate Professor Li said while cleaner production helped, reducing demand was “another very large mitigation opportunity”.

He said supply-side decarbonisation remained essential; cleaner electricity was especially important and recycling increasingly valuable. But, he added, without the additional measures tested, the global battery supply chain could generate around 19-23 billion tonnes of CO₂-equivalent emissions through to 2050.

“Combining ambitious supply- and demand-side strategies cuts this to around 9-12 billion tonnes – roughly half,” Associate Professor Li said. “Within that overall reduction, supply-side measures account for around 3.5-4.7 billion tonnes of mitigation, while demand-side strategies account for around 6-7 billion tonnes,” Associate Professor Li said.

“These are emissions reductions on the scale of the annual emissions of a major global economy such as the EU.”

Lead and first author Dr Haiwei Zhou, also from the Faculty of Engineering and Information Technology, said the team now hoped to improve the model’s regional resolution, as mining, refining, electricity and environmental pressures varied greatly between locations.

“We also want to test whether the same supply-versus-demand dynamic appears in other rapidly growing clean-energy supply chains such as wind turbines and solar panels,” Dr Zhou said. “For policy and industry, battery decarbonisation should move beyond regulating production emissions alone.”

Co-author Professor Prakash Singh from the University of Melbourne Faculty of Business and Economics agreed that new policies could help.

“Policies can also encourage longer battery lifetimes, appropriate battery sizing, higher utilisation and second-life applications,” Professor Singh said. “The broader question should be not only ‘How low is the carbon footprint of each battery?’, but also ‘How much battery capacity do we actually need to provide the service?'”