Modeling of the Residence Time Distribution in a Continuous Electrode Slurry Mixing Process in Battery Cell Production

Battery cell production is costly, especially due to expensive raw materials and high scrap rates, making continuous process optimization essential. Electrode manufacturing, particularly the mixing process that defines the fundamental electrochemical properties of a battery, offers great potential for increasing material efficiency. Understanding the residence time and residence time distribution (RTD) of particles within the continuous mixing process is crucial for optimization. Autonomous process control requires accurate prediction of the RTD to enable precise and resource-efficient rejection of nonconforming material. Similarly, knowledge of the RTD is required to ensure the traceability of battery cell materials within the mixing process. A model developed from experimental data is presented that simulates the RTD of a twin-screw extruder based on the input process parameters screw speed, mass flow, and solid content. This is possible for the entire system and the subsystems process section, solvent dosing unit, binder dosing unit, and powder dosing unit. As a result, the characteristic times can be predicted with a very high degree of accuracy from when the raw materials are added to the final slurry at the end of the continuous mixing process. ... mehrThis enables resource-efficient production and provides detailed information for traceability in continuous mixing processes.