Fraunhofer Institute for Production Technology IPTResearch project "ECO-iL-DRY"
Lithium-ion batteries as a key technology for the energy transition
Without lithium-ion batteries electric mobility – an important field of application for renewable energies – would be unthinkable in its current form. In order to reduce the manufacturing costs for such batteries, the industry has to make electrode drying processes faster and more energy-efficient. In the research project ECO-iL-DRY, researchers are developing a laser hybrid dryer that can dry battery electrodes faster, more efficiently, and at a higher quality than conventional methods.
Coating and drying battery cells
To manufacture the anodes and cathodes of battery cells, the industry deposits electrodes as a liquid mixture of active material and solvent, known as "slurry,” to copper or aluminum foil. The solvent contained in the mixture must then be completely removed to create a stable and porous electrode, which is necessary for an electrochemical reaction. This drying step is crucial for the quality of the final battery – and this is exactly where the ECO-iL-DRY project comes in.
Why new drying technologies are needed
Drying the electrodes is one of the most energy-intensive and technically demanding steps in battery cell production. Conventional methods use hot gas or infrared radiation for the drying processes. However, this often leads to high energy consumption and, if drying is inhomogeneous, to sample defects. The laser system being developed by the researchers in this project enables more uniform, faster, and more energy-efficient drying.
Drying battery foils with lasers
The project aims to reduce costs and improve quality in the battery foil drying process, thereby making battery production more sustainable and energy-efficient.
The partners in the ECO-iL-DRY project are working on three key areas to achieve this:
- A new laser module is being designed to generate highly uniform radiation zones, to consume less energy and to reduce the space required for drying equipment.
- An intelligently controlled hybrid drying process will improve the quality of the electrodes with the aid of thermography and layer thickness measurement.
- Finally, an optimized prototype will show how laser and hot air drying can be combined and how the resulting waste heat from the laser module can be used to preheat the dryer air. The system is designed to be scalable and particularly energy-efficient.
In addition to the laser system, the project team is developing a digital process chain to not only optimize the drying process for battery foils, but also to make it more transparent and controllable. To this end, the project partners are linking sensors, models, data analysis, and automatic control together. The result is a fully data-driven and automated drying system that can be easily adapted to different production sizes and facilitate the transition to series production.
The Fraunhofer IPT's role in the project is to develop the system technology for the hybrid dryer and to construct the dryer. This includes the laser module, the integration of sensors, the control of the process, and test operation.
Consortium:
- Bernd Münstermann GmbH & Co. KG
- Dilas Diodenlaser GmbH (Coherent-Dilas),
- Fraunhofer Institute for Production Technology IPT, Aachen
- Fraunhofer Research Institution for Battery Cell Production FFB, Münster
- MESSTEC Power Converter GmbH, Penzberg
Funding
The ECO-iL-DRY research project is funded by the German Federal Ministry of Research, Technology and Space (BMFTR) as part of the funding initiative Research and Development in Battery Technologies for Technologically Sovereign, Competitive, and Sustainable Battery Value Chains (B@TS).
Funding code: 03XPB026A
Project management agency: Projektträger Jülich PTJ