Electrode drying in the roll-to-roll process is one of the most cost- and CO2-intensive manufacturing steps in the production of lithium-ion batteries. This could change.
With the demonstrator developed in the project, the drying process was scaled up to industry-typical feed rates.
Laserline GmbH
The IDEEL research project has developed a laser-based roll-to-roll process that reduces the time needed to dry the electrode by over 60% and achieves a web speed of 30 m/min. According to a statement by Laserline GmbH, which was involved in the project, a conventional oven-based convection drying process was combined with a laser drying process based on high-power diode lasers.
In addition, a laser booster at the beginning of the process halves the required oven length. The operating costs of the drying process are expected to fall by 20 to 30% overall. The reduced oven operation with simultaneous use of the system until the end of its service life also optimizes the CO2 balance. The new approach should thus enable more economical and climate-friendly processes.
New Materials Designed
The research partnership initially focused on developing a suitable laser drying process. To this end, new materials for anode and cathode coating were specially designed for use with lasers, and aqueous formulations based on graphite, lithium iron phosphate and silicon graphite were tested. A diode laser system with an electrical efficiency of more than 50% was used as the heat source.
On this basis, a modular laser drying unit with an air concept and double-chamber slot dies for applying the water-based battery pastes was developed. Within this demonstrator, the drying process was scaled up to industry-typical feed rates and the process configuration was validated.
Project Partners
The project partners included the Production Engineering of E-Mobility Components group at RWTH Aachen University, Coatema Coating Machinery GmbH, Optris GmbH & Co. KG, the Fraunhofer Institute for Laser Technology, the Münster Electrochemical Energy Technology Battery Research Center at the University of Münster, and the Fraunhofer Battery Cell Research Production.
This is a partly automated translation of this german article.
