New research has found that an often-overlooked step in the lithium-ion battery recycling process (the pre-treatment stage) plays a decisive role in determining both environmental impacts and the recovery efficiency of valuable metals.
Published in Nature Sustainability, the Monash University study revealed that the pre-treatment phase can account for up to 38 per cent of the total environmental impact of the recycling process.
The stage also significantly influences material losses, with outcomes varying according to battery type and treatment method.
Pre-treatment refers to the first major step in recycling, during which spent batteries are broken down into a material known as “black mass.”
This powdery substance contains key metals such as lithium, nickel, and cobalt, which are later recovered for reuse.
Despite its central role, the new research suggests pre-treatment is frequently neglected in both academic study and industrial recycling strategies.
Led by the Department of Civil and Environmental Engineering, the study compared three main industrial pre-treatment approaches (mechanical, thermal and chemical) and found distinct trade-offs between environmental performance, recovery efficiency, and operational complexity in each.
Professor Victor Chang, Deputy Head of the Department, said the findings demonstrate that early design choices in the recycling process can shape system outcomes long into the future.
“While many countries are planning to invest in and scale up battery recycling industries, our work highlights an important aspect of the process – the pre-treatment stage,” Professor Chang said.
“This step is often overlooked, but it can be critical in determining the efficiency, safety, and overall effectiveness of downstream recycling processes.”
He added that an integrated and evidence-based approach is essential for countries seeking to build sustainable battery recycling systems.
“Lithium-ion battery recycling is not just a technical challenge – it’s a system design challenge. Pre-treatment shapes both recovery efficiency and environmental outcomes,” he said.
“Decisions made at this stage will affect system performance for decades, so it’s vital that they are guided by robust evidence.”
As nations expand their recycling infrastructure in response to surging demand for electric vehicles and energy storage, the study offers timely guidance for both policymakers and industry stakeholders.
By accounting for pre-treatment in system planning, recycling operations could reduce emissions, improve metal recovery rates, and create more resilient supply chains for critical materials.
The findings ultimately underscore the importance of designing recycling systems that are not only technologically sophisticated but also environmentally optimised from the outset.
