German scientists develop new electrode production process to speed up battery production

Introduction: Researchers at Karlsruhe Institute of Technology (KIT) in Germany have developed and successfully applied an innovative concept for coating and drying two layers of electrodes at the same time, which can significantly speed up the production of batteries .

KIT said the process developed by the Thin Film Technology (TFT) Research Group can reduce drying time to less than 20 seconds, reducing production time by one-third to one-half compared to current methods, making lithium-ion battery production faster and cheaper.

However, it is still a wet chemical process. The active materials are mixed in powder form and stirred with a binder and solvent to form a paste (slurry). This paste is then applied thinly to a carrier medium, usually aluminum foil, and dried in an oven to evaporate the solvent and cure the coating.

Drying usually takes about one minute, so at production speeds of 100 meters per minute, correspondingly long drying distances are required. By combining the process steps of coating and drying, the KIT research team succeeded in developing a concept that proceeds simultaneously.

Specifically, the synchronous concept uses different active materials for the individual layers and applies them simultaneously. One layer is responsible for adhesion and one layer is responsible for specific capabilities. This layer structure, roughly divided into one third and two thirds, enables production with extremely high drying rates and reduces drying time to one third.

"Our work shows that we have in principle mastered all the process steps to produce batteries faster without compromising quality and thus more cost-effectively in the future," says Professor Wilhelm Schabel. Moreover, despite the reduced drying time, there is no loss in capacity and therefore no impact on the battery's range .

In their study, the scientists applied different active materials distributed in the anode layer with different thicknesses. Different properties are specifically distributed in the electrode layer. As a result, the electrode can be tailored and exhibit better mechanical as well as electrochemical properties.

The group is currently investigating various ways to scale up the synchronization concept. To this end, they are testing pure convection drying with high-performance nozzles and laser drying modules. "Our research shows that in principle it is possible to increase the speed of battery production by 200 to 300 percent in the future," said Professor Schabel.