Towards Autonomous Battery Cell Production : A Digital Twin for Continuous Slurry Mixing

Continuous mixing process in battery cell production is characterized by high complexity, strong processmaterial interactions, and limited transparency compared to the batch process. In addition, high material costs and significant scrap rates further increase the economic pressure on production systems. The lack of automatic process control and the difficulty of validating control strategies prior to operation pose major challenges for ensuring product quality, process stability, and safe plant operation. This paper presents the first fully functional digital twin (DT) for a continuous slurry mixing process
in battery cell production, which is bidirectionally coupled to a real twin-screw extruder. The developed DT combines real-time data acquisition, control code validation, automated process control, traceability, and secure data storage within a unified framework. A safety system consisting of a simulation-based safety filter and a real-time safety program enables early detection of control code errors using a Software-in-the-Loop approach. A key contribution is the implementation of residence time distribution (RTD) based traceability, enabling the definition of virtual batches and allowing both forward tracking and backward analysis of material flows. ... mehrIn addition, a comprehensive quality score is calculated based on multiple process and product indicators. To ensure data integrity, the DT is coupled with a Blockchain, providing a tamper-proof and chronological data history. Experimental validation demonstrates real-time control capability, risk reduction, and efficient process optimization, establishing a foundation for highly automated and intelligent battery production.