Fraunhofer IFAM develops electrochemical process for battery recycling
A new process is to recover valuable raw materials from used batteries. It already works in the lab, and a large pilot plant is under construction.
Chassis of an electric car with batteries: a specific electrode for each raw material
(Image: Audi)
The Fraunhofer Institute for Manufacturing Technology and Applied Materials Research (Fraunhofer-Institut fĂĽr Fertigungstechnik und Angewandte Materialforschung, IFAM) has developed an electrochemical recycling process for batteries. It is intended to be less energy-intensive and produce fewer carbon dioxide emissions than conventional hydrometallurgical processes.
The Fraunhofer team from Bremen has developed electrodes for recovering raw materials, manufactured using screen printing. For this purpose, the process water generated during recycling is fed into an electrochemical reactor containing the electrodes.
“Thanks to their special properties, the electrodes selectively extract ions from the wastewater and store them,” said Cleis Santos, head of the Electrochemical Processes for Recycling and Water Treatment group. “For example, they can bind lithium ions – and at the end of the process, we obtain the separated material in powder form and with high purity.”
The researchers' idea is to adapt the electrodes so that each one functions for a specific raw material: for lithium as well as for cobalt, copper, or nickel. Even the so-called rare earth metals, which currently have to be imported, are to be recovered from old batteries or electronic scrap in this way.
Recycling of various raw materials
“In the long term, it is conceivable that in a large plant, the wastewater will be passed through several reactors,” explains Santos. “This way, we could recycle different critical raw materials within the same plant.”
In addition, the electrochemical process has various advantages over the hydrometallurgical processes that are commonly used, says the Fraunhofer team: It requires less energy and is therefore cheaper. Furthermore, less carbon dioxide is emitted, and no chemicals such as alkalis or acids are used.
“According to EU regulations, manufacturers will increasingly have to prove the entire CO₂ footprint from raw material to product in the future, and new products must also contain more recycled material. The question of efficiency and quality of recovery is therefore becoming increasingly important,” said Julian Schwenzel, Head of the Electrical Energy Storage Department at Fraunhofer IFAM.
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Fraunhofer IFAM has shown that the process works in the laboratory. Now the team is working on a large pilot plant. In addition to recovering raw materials, the process is also suitable for seawater desalination and the treatment of hospital wastewater.
(wpl)
