Researchers at Cornell University have developed a battery recycling method that could significantly extend the life of lithium-ion batteries while reducing dependence on critical minerals such as nickel and cobalt. The new process, called direct electrode-to-electrode regeneration (DEER), restores spent battery electrodes without destroying and rebuilding them, offering a more efficient alternative to conventional recycling methods.
Published in Energy and Environmental Science, the study was led by postdoctoral researcher Kiwon Kim under the direction of Vibha Kalra. The work addresses a growing challenge for the battery industry: securing supplies of critical minerals while managing increasing volumes of end-of-life batteries.
Traditional recycling relies on pyrometallurgy or hydrometallurgy. These approaches either melt batteries at high temperatures or shred them into a powder that is treated with harsh acids. Although valuable metals can be recovered, the materials must then be resynthesized and refabricated into new battery components, creating a lengthy and expensive recycling loop.
The DEER process takes a different approach. Instead of shredding batteries, researchers remove intact electrodes and place them in an electrochemical solution known as 1,3-dimethyl-2-imidazolidinone. The solution dissolves the solid electrolyte interphase, an insulating layer that forms during battery use and gradually reduces performance. By removing this layer, the electrodes can be restored and reused directly in new batteries.
Tests showed that regenerated batteries recovered up to 95% of their original capacity. Economic and environmental analyses conducted with collaborators at Argonne National Laboratory found that the process could reduce recycled cell manufacturing costs by 56% while lowering water consumption and harmful air emissions compared with existing recycling techniques.
The researchers are now working to scale the technology for industrial battery systems and address additional degradation mechanisms, including lithium loss. If successful, DEER could shorten the battery recycling loop, reduce reliance on imported minerals, and strengthen the sustainability of electric vehicle and energy storage supply chains.