The mixing step for electrode slurry preparation in the manufacture of batteries is highly relevant because it directly affects the downstream production processes and the performance of the battery cells. In this work, a study of the flow behavior and material strain in a twin‐screw extruder is carried out to analyze its efficiency for continuous battery slurry processing. Here, individual elements of the extruder screw are simulated using the smoothed particle hydrodynamics method. Based on the resulting flow profiles, a dimensionless analysis is used to validate the calculations. Hence, the local shear rate and pressure profiles are evaluated for different screw geometries. The effects of the screw design and process setup are discussed, to accordingly improve the mixing process.

Screw design in the extrusion process has an important effect on the distribution of material through the extruder, resulting in partially filled sections in the processing zone. Accordingly, the local accumulation of material in the extruder leads to variations in material strain conditions and also influences the local residence time of the material in a given screw section. This work evaluates particle dispersion in anode slurry considering three different screw arrangements. The particle size distribution is considered as a quality parameter representing the microstructure of the battery slurry components and their distribution. Numerical simulation of the material flow behavior through a laboratory extruder was performed to investigate the filling ratios and resulting shear rates for different screw designs and process conditions. The importance of process parameters and a suitable screw configuration to achieve specific particle sizes in battery slurry is discussed.

Driven by the increasing demand for high‐performance batteries, this study addresses the need for efficient and scalable mixing processes in battery manufacturing, focusing on continuous mixing in twin‐screw extruders. While extruders can operate at different production rates, process limitations require a scale‐up to larger extruder sizes to further increase production capacity. This work compares the quality of anode slurries produced under equivalent process conditions on four different scales of twin‐screw extruders. It was shown that the transfer from laboratory to pilot and production scale, while maintaining consistent product quality, i.e. dispersion of the conductive additive, is feasible. Flow simulations were used to quantify the material strain in each process setup, thereby facilitating the identification of relevant scale‐up criteria and even allowing for process transfer to similar but not geometrically equivalent screw geometries. Additionally, the influences of different process parameters such as screw speed and mass flow rate on the dispersion quality were quantified and compared between scales. In short, processing with a specific feed load smaller than 0.01 was shown to provide better dispersion and electrode quality across scales.