Physics-Based Derivation of Scrap Probabilities in the Stacking Stage of Battery Manufacturing

The reliability of production systems can be assessed with the help of discrete-event simulations. For that purpose, it is necessary that failure probabilities of each individual production stage are quantified. As an example, we consider the stacking stage of battery manufacturing. On the one hand, failures are due to defects in manufacturing equipment caused by component wear. On the other hand, also defective products themselves represent a reason for a decrease of the efficiency of a production chain. Many defective products result from the fact that certain manufacturing tolerances are exceeded. An optimization of the process control loops then has to be performed to reduce the likelihood of such kind of defects. To systematically analyze the probabilities of defective products, it is necessary to interface system-level discrete-event simulations with information obtained from physics-based process simulations. For that purpose, this publication presents a suitable approach for quantification of scrap probabilities that is illustrated for the stacking of individual electrodes within battery manufacturing by relating the likelihood of excessively large electrode deflections to the cycle time of the stacking process.