Structuring films at record speed
Batteries play a major role in our time. These energy stores are in ever greater demand, very much so also for electric cars, smartphones or laptop computers. However, there is one problem: Manufacturing costs of batteries are high, among other things, because of the slow process of coating electrode films.
State of the art
The electrodes in a lithium ion battery must be coated so that lithium can be stored and released again. For this purpose, a paste of active material is applied to an electrode film of copper or aluminium. Also intermittent (sectional) electrode patterns are known: These designs have a strip of uncoated film between coated sections which later serves as an electrode lead. In order for the batteries to work reliably, it is also important that the coated sections have precise starting and stopping edges.
KIT scientists of the Institute of Thermal Process Engineering (TVT) - Thin Film Technology (TFT) developed a procedure which accelerates this intermittent coating process. Unlike previous techniques, a fixed nozzle can be used to apply the coating paste. The film to be coated is continuously advanced below this nozzle. The newly developed nozzle is equipped with a special membrane whose movement can abruptly stop the coating paste. The coating section is given a very precise stopping edge in this way even at high speeds.
The scientists established a new speed record for intermittent coating with this technique. Instead of the usual maximum of 30 m, the new technique allows up to 100 m of coated film to be produced per minute, and that at improved start and stop edges.
Options for companies
The technique can also be used for other products for which patterns must be created on large areas, such as coatings of bonding material. The KIT has already successfully applied it in electrode coating and is now looking for partners interested in further developing and using the technique in various applications.
Your contact person for this offer
Dr. Aude Pélisson-Schecker,
Karlsruhe Institute of Technology (KIT)
Innovation Manager Energy, Innovation and Relations Management (IRM)
Phone: +49 721 608-25335