Multiscale simulation approach for production systems: Application to the production of lithium-ion battery cells

Planning support for industrial production systems aims at reducing production-related costs and environmental impacts while creating required products with a desired quality. However, the increasing complexity of modern products and production technology makes planning and the provision of appropriate methods and tools a challenging task. Isolated measures for improving quality, cost or eco-efficiency, often result in problem shifting causing negative effects regarding other goal criteria. For this reason, suitable methods and tools are required for the planning and evaluation of specific improvement measures and for obtaining an interdisciplinary system understanding. This paper presents an approach, which is capable of analyzing production systems considering multiple scales based on coupled simulation models. The approach enables the evaluation of interactions between product units, processes, machines, technical building services, and the building structure. The approach contains a generic framework for the simulation structure, detailed model concepts for relevant production system elements, and a definition of interfaces between models for co-simulation. A case study demonstrates an exemplary application of the simulation approach for the production of battery cells. The study shows how the simulation enables evaluating the influences of different process configurations on intermediate product characteristics as well as of different factory scenarios and seasonal effects on the energy demands. More specifically, on product and process scale, the study revealed how different process routes and process parameters in electrode production affect the characteristics of battery slurries and coated electrode foils along with production lead-times. On process chain and factory scale, the study illustrates how the energy demands of machines and building services are influenced by machine operation and outside weather conditions. Thus, the study provides insight into the capabilities of a multiscale simulation and how such simulation may be applied to evaluate different producton system configurations, operation strategies, or facility locations.