According to foreign media reports, the research team of the Karlsruhe Institute of Technology (KIT), using a new coating process, produces lithium-ion battery electrodes at record speeds. At the same time, the new process improves electrode quality and reduces production costs.
When the battery electrode is produced, the electrode material is coated in a rectangular shape on a copper foil or an aluminum foil in the form of a thin paste. Next to the rectangle is the uncoated foil, which is a necessary condition for conducting current. In order to produce these profiles, the painting process must be interrupted and restarted repeatedly. At very fast production speeds, how to make the material not be applied to the edges of the rectangle is a big challenge. Accuracy is the key to electrode coatings, and even small production errors can make the battery unusable. Professor Wilhelm Schabel of KIT said: "The current price of lithium-ion batteries is much higher than the actual value due to low output and high scrap rate."
The research by Raf Diehm, a Ph.D. student in the Schabel research group, has made decisive progress. He optimized the nozzles used to produce electrode materials with a vibrating membrane to periodically stop and restart the paste coating application. Diehm said: "This film is much lighter than mechanical valves, and the reaction speed is very fast, which greatly increases the production speed. Previously, the manufacturing process was only 30 to 40 meters per minute. With the new technology, the electrode coating can be It reaches 150 meters per minute. "In the electrode production, reducing mechanical parts not only speeds up the production process, but also has the further advantage: the control of the diaphragm is much more precise than the mechanical valve, which can improve the production quality and reduce the scrap rate. ”
Dr. Philip Scharfer and Professor Schabel have been studying this topic for several years. He explained, “In order for battery production to benefit from faster electrode coatings, the production process must be adjusted elsewhere.” The coating is faster and the drying time needs to be shorter. Otherwise, the dryer section and the entire system must be expanded accordingly. “KIT conducts basic research on different drying conditions, optimizes the drying process, and reduces the drying time by about 40% while maintaining electrode performance.
This technology has greatly reduced battery production costs and helped meet the growing demand for electric travel, now moving from lab to industrial production. In the future, KIT will work with Ulm University to develop batteries.