Despite being less carbon intensive, researchers identify other environmental risks associated with battery recycling
The sales of electric vehicles in 2020 jumped by nearly 40 per cent. Impressive as that growth is, what makes the feat incredible is the fact that overall car sales during the year fell by about 14 per cent amid the COVID-19 pandemic fallout. A key concern associated with the rapid increase in EV market share has been the sustainability of batteries. While recycling has been the central plank around which the battery supply chain could be balanced, there is little in terms of evidence on the sustainability of the recycling process. New research at Finland’s Aalto University now has shed some light on the environmental burden of battery recycling as compared to new production.
As far as carbon intensity goes, the study found that the carbon footprint of the raw materials obtained from recycling batteries was 38 per cent lower than the footprint of electric car batteries made with virgin raw materials. The difference is greater when aluminium and copper recovery during the mechanical pre-treatment is included.
Researchers arrived at this conclusion through a simulation-based life-cycle analysis which considered energy and water consumption, and emissions from the hydrometallurgical recycling process— more commonly known as smelting. Smelting, the most prevalent method used for battery recycling, typically loses lithium and other raw materials. This issue can be addressed with novel hydrometallurgical processes which allows for the recovery of all metals. These processes though are resource intensive, and can produce contaminated wastewaters. In addition, despite being less carbon-intensive, recycling was found to have a significant increase in the ozone depleting potential from the recovery processes.
“Battery recycling processes are still developing, so their environmental footprints haven’t yet been studied in detail. To be beneficial, recycling must be proven to be more ecological than producing raw materials – we can’t just assume recycling is automatically better, even though we know mining the raw materials has large environmental impacts, like high energy and water consumption,” said – Mari Lundström, a co-author of the study and an assistant professor at Aalto University, in a statement following the study’s publication.
According to the researchers, this kind of analysis is crucial to determine how process parameters affect the overall environmental impacts. The team also recommended mechanical pre-treatment of batteries to enable recovery of aluminium and copper, and the re-use of the waste as the reductant in the process to further reduce the environmental costs of the process and increase industrial scalability. “We will have a massive need for recycling, and we have to find the most viable and ecological recycling processes. Research into technological innovations and their environmental impact go hand in hand,” added Lundström in the brief.