Fraunhofer Institute for Industrial Mathematics ITWM
Battery foils are the main components in lithium-ion battery cells. The continuous monitoring of material parameters – layer thickness and conductivity – is crucial for product quality. We use our terahertz measurement technology to monitor them inline during production. The measurements are carried out inline on single- and multi-layer coatings at various points in the wet or dry process – always contact-free and non-destructive.
Lithium batteries – used in electric vehicles and large battery storage systems – consist of anode and cathode foils that must have different properties depending on their function. Measuring these properties, in particular the conductivity and layer thickness, is essential in the development and production of efficient batteries in terms of energy density and longevity.
Cathodes are characterized by low conductivity. Anodes, on the other hand, have a significantly higher conductivity, which makes them more difficult to measure. Nevertheless, with our photonic terahertz FMCW systems, which have been specially optimized for this application, we are able to generate precise information about the several 10 μm thick foils.