Dry-processed cathodes can now be recycled without toxic solvents

Dry-processed electrodes that do not require expensive and sometimes toxic solvents and instead use polytetrafluoroethylene as a binder could make battery cell production more environmentally friendly and cost-effective.

A research team from the MEET Battery Research Center and the Institute of Business Chemistry at the University of Münster has now developed a method for recycling such dry-processed cathodes—an important step toward circular batteries.

Innovative production processes such as dry electrode processing are a crucial milestone toward a more environmentally friendly and cost-effective battery cell production. This approach completely avoids the use of expensive and partly toxic organic solvents, achieved by selecting the appropriate binder: the high-temperature plastic polytetrafluoroethylene (PTFE).

To strengthen the circular economy of batteries with such processes, it is essential to integrate recycling possibilities from the very beginning. A team from MEET Battery Research Center and the Institute of Business Chemistry at the University of Münster has therefore developed a method for the scrap recycling of dry-processed lithium ion battery cathodes.

The results have been published in the journal Advanced Energy Materials.

“The recycling can be successfully implemented and scaled up dry mechanically using mills,” says Maike Michelle Gnutzmann, Ph.D. student at MEET Battery Research Center and International Graduate School BACCARA.

For dry-processed cathodes, the mills separate the cathode composite from the current collector and granulate it. As a result, all components, such as active material, PTFE binder and conductive carbon black, are available in their original form.

“Since the materials involved are not degraded by the recycling process, they can be directly reused,” says Maike Michelle Gnutzmann.

In addition, the Institute of Business Chemistry evaluated the profitability of the procedure through a life cycle cost assessment (LCCA). The results show that the recycling process is attractive for industrial applications, not only for sustainability considerations but also for cost efficiency.