Single-step battery cathode recycling

(Press-News.org) A new battery recycling method developed by Illinois Grainger engineers removes scarce, expensive metals from old battery cathodes and coats them onto new cathodes in a single step. The result is significantly more affordable, less environmentally impactful and less risky to health than any recycling method currently in use.

Battery cathodes – the positive part of the battery that helps to store electrical energy – often require rare, expensive metals such as cobalt. It is therefore crucial to develop effective means for recycling cathodes that reclaim the metals essential to their operation.

Researchers in The Grainger College of Engineering at the University of Illinois Urbana-Champaign have invented a single-stage process for simultaneously extracting metals from old cathodes and creating new cathodes. Focusing on lithium cobalt oxide, the cathode material most used in phone and laptop batteries, the researchers demonstrated that a single electrochemical process can be used to dissolve the material from a spent terminal and deposit it on a new one. As reported in the journal Advanced Functional Materials, the new process is one-eighth as costly and over 50% less impactful than common recycling processes.

“The fact that our process is a single step makes all the difference because the material needs are less than half those of other recycling processes,” said Jarom Sederholm, an Illinois Grainger Engineering chemical and biomolecular engineering graduate student and the study’s lead author. “We collaborated with colleagues in the Department of Industrial and Enterprise Systems Engineering to analyze both the cost and environmental impacts of performing this process at scale. On every factor considered, our process is better.”

Paul Braun, an Illinois Grainger Engineering materials science and engineering professor and the project lead, said, “Current methods for recycling battery cathodes involve too many steps. The cathodes must be broken down, separated and purified, reformed through chemical reactions, and then coated onto new battery components. The processes require considerable energy and chemical inputs, which increases the cost, the potential for environmental harm and risks to human health.”

Sederholm recalls that the idea for the new process came from a hypothetical discussion with Braun.

“Our research group works extensively with electrodeposition – a mechanism by which electrical charge is used to layer a material on a substrate – and has significant research infrastructure,” Sederholm said. “One day, we had a thought: if electrodeposition is possible, then the reverse should also be true. It should be possible to use electricity to dissolve a coating too. So, I went in the lab, set everything up with the right solution and voltages, and the cobalt lithium oxide coating on a cathode came right off.”

Since the required metal was already dissolved in solution from the stripping process, inserting a new cathode into the solution and coating it by electrodeposition was the next logical step. The entire recycling process – reclaiming the valuable metals and reusing them in a new product – takes place as one stage and one reaction in a single chemical bath.

To assess the total cost and impact of the new single-state method, the researchers turned to colleagues in the Illinois Grainger Engineering Department of Industrial and Enterprise Systems Engineering: graduate student Zheng Liu and professor Pingfeng Wang. They determined that the new method outperforms all techniques currently in use by four metrics: economic efficiency, environmental impact, impact on resources, and human health risk.

The study focused on lithium cobalt oxide cathodes for its prevalence in consumer electronics, but Sederholm plans to extend these results into other cathode chemistries.

“There are many battery technologies based on nickel and manganese oxides, and they would have different requirements for this to work,” he said. “Also, both the cathode and anode can contain binding additives such as polyvinylidene fluoride (PVDF), that may be harmful when released into the environment. We want to see if we can mitigate the amount released and even recover other additives for reuse.”

Sederholm, Braun, and Illinois Grainger Engineering materials science and engineering postdoctoral research associate Arghya Patra have filed for an international patent on technology derived from this study.

Jr-Wen Lin and Carlos Juarez-Yescas also contributed to this work.

The study, “Single-Step Electrochemical Battery Recycling,” is available online. DOI: 10.1002/adfm.202511009ope

Support was provided by the National Science Foundation Future Manufacturing Research Grant.

Illinois Grainger Engineering Affiliations

Paul Braun is an Illinois Grainger Engineering professor of materials science and engineering in the Department of Materials Science and Engineering. He is affiliated with the Department of Chemistry, the Department of Mechanical Science and Engineering, the Department of Chemical and Biomolecular Engineering and the Beckman Institute for Advanced Science and Technology. He is director of the Materials Research Laboratory and holds a Grainger Distinguished Chair in Engineering appointment.

Pingfeng Wang is an Illinois Grainger Engineering professor of industrial and enterprise systems engineering in the Department of Industrial and Enterprise Systems Engineering. He holds Jerry S. Dobrovolny Faculty Scholar and Donald Biggar Willett Faculty Scholar faculty appointments.

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