Shredding instead of melting: Improved recycling of lithium-ion batteries
Whether in smartphones, notebooks, electric cars or electric scooters - they keep the modern electric world running. But even lithium-ion batteries only have a limited lifetime. But they contain valuable raw materials such as cobalt, nickel, copper and lithium. The European Union has set itself a recycling target of 50 percent. In order to increase this figure, the TU Bergakademie Freiberg is researching further possibilities for mechanical processing in the joint project "InnoRec".
Up to now, lithium-ion batteries have usually been melted down in the course of recycling and later chemically separated from one another. This is very complex and expensive. This is because a battery or accumulator consists of a complex mixture of materials, including graphite, aluminum, copper, nickel, cobalt, manganese and lithium. The exact composition of the respective components differs from manufacturer to manufacturer, which makes preparation even more difficult.
In order to be able to recover lithium in particular better and in larger quantities, the scientists at the Institute of Mechanical Process Engineering and Processing Technology (MVTAT) at the TU Freiberg rely on classical processing techniques such as crushing, drying and sorting. These techniques can be adapted to different lithium-ion batteries. The end result should be small shredded battery components. These are sorted with the help of an air stream so that in the end only the heavy metal particles remain from the casing. Compared to the melting process, these can be recovered and are thus available again to the material cycle as secondary raw materials.
"But the proper disposal of old batteries and accumulators is also essential for our approach. Until now, far too much still ends up in household waste or remains in the drawer at home," explains Prof. Urs Peuker of MVTAT.
The aim of the "InnoRec" project in the "ProZell" competence cluster, which is funded by the Federal Ministry of Education and Research until 2022, is to make battery recycling more efficient in terms of materials and more robust in relation to advanced and newly developed battery materials. This approach is also to be used later for new battery systems and electronic scrap. In addition to the TU Bergakademie Freiberg, the TU Clausthal, the TU Braunschweig, the RWTH Aachen and the MEET in Münster are involved. The results of the project will be incorporated into the teaching - especially in internships and lectures - of the universities and will be the basis for final theses.