The goal of the project ExZellTUM II is to analyse and optimize silicon anodes and high-voltage cathodes in large-format lithium-ion cells as well as to achieve the cross-process optimization of the production steps. The developing steps includes the targeted control of the electrode structure, improvement of the cell design, production processes for semi-finished products and cell assembly, fundamental investigations on electrolyte filling and cell formation as well as an explanation of the aging mechanisms, especially of cells based on electrodes with high surface area capacities. While promising data on laboratory cells are available, the continuous electrolyte consumption, irreversible losses of active lithium during formation and the volume expansion at electrode and cell level, especially large-format cells, are not solved. Therefore, the decisive challenges of scaling-up for applications are at the heart of ExZellTUM II.