The increased focus on electromobility in European countries is closely linked to the establishment of local lithium‐ion battery (LIB) mass production facilities, such as Tesla's Gigafactory 1 in Nevada. While extensive knowledge in LIB lab‐scale assembly already exists, the transfer to industry‐scale production is an area of challenge that is tackled through intense production research. Slurries of nickel‐rich NMC811 that is sensitive to environmental conditions, and therefore more difficult to process, are successfully up‐scaled to 65 kg industry‐scale batches and investigated through rheological measurements. Defect‐free, double‐side‐coated electrodes with ≈400 m in length are obtained via slot‐die coating and assembled into large‐scale PHEV‐1 cells with graphite as the counter electrode. Possible production‐induced defects are examined through computed tomography (CT). The obtained qualified, automotive cells are investigated through galvanostatic charge/discharge testing that confirms excellent cycling performance with discharge capacities of 26.3 Ah (1st cycle) and 25.4 Ah (300th cycle), which corresponds to a capacity retention of 96.6%. These results are compared with NMC811‐containing cells from lab‐scale/literature, and large‐scale products (slurries, electrodes, and PHEV‐1 cells) containing the predecessor material NMC622. The scalability of slurry preparation, electrode production, and cell assembly with special emphasis on differences between lab‐scale and industry‐scale production is discussed.

Li-ion cells of the industrially-relevant formats PHEV1 (prismatic), multi-layer pouch, and 21700 (cylindrical) are directly compared by experiments for the first time. All three cell formats were reproducibly built on pilot-scale with the same anode (graphite), cathode (NMC622), separator, and electrolyte allowing a direct comparison. The main differences between these formats are their capacities (24.6 Ah, 2.2 Ah, 2.3 Ah), volume/surface ratios, as well as tab and the jellyroll/stack configurations (flat-wound, stacked, wound). The comparison involves voltage curves during formation (0.1 C), discharge rate capability (0.5 C−3 C), heating behaviour, cell impedances, geometrical properties such as electrode curvatures and tab configurations, as well as comparison with coin half cells with anode and cathode vs Li counter electrode. The data are put into context with commercial and pilot-line built cells from other studies.

Despite intensive research activities on lithium‐ion technology, particularly in the past five decades, the technological background for automotive lithium‐ion battery mass production in Europe is rather young and not yet ready to meet requirements of automobile manufacturers. In light of the strong increase in electromobility, bridging this gap between fundamental research and industrial production is mandatory to keep the value chain of automobile manufacture in European countries. Challenges in know‐how transfer from lab scale to industry scale arise from different product configurations and objectives. Lab scale focuses primarily on material development and screening, utilizes small‐sized half‐cell or single‐layered designs with one‐side‐coated electrodes, and applies manually operated, discontinuous equipment, whereas industry focuses on optimized trade‐offs between throughput, quality, and costs. Market‐relevant cells contain usually double‐side‐coated electrodes with comparatively higher areal capacities, assembled into multilayered configurations. Mass production is conducted through automated, continuous processes including roll‐to‐roll manufacturing and consecutive pick‐and‐place operations. Inevitably, standard laboratory conditions do not allow for prediction of either optimized mass‐production process parameters nor physicochemical characteristics of final products. Hence, this Review aims to identify challenges in transferring lab‐scale results to industry with special focus on pilot lines as intermediate step between the different technological levels.

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During the production process of lithium‐ion battery cells, the filling, which consists of dosing and wetting steps, of the cell and its components with an electrolyte liquid is important for the quality and costs of the final product. The cell format as a combination of housing and cell arrangement not only determines the type of filling process but also influences the distribution of the electrolyte within the cell. The cell format also has an influence on the wetting state as a function of time. Herein, in situ neutron radiography is used to analyze the filling process of two different cell types – pouch cells with a z‐folded stack and hardcase cells with a flat wound roll. The results are then analyzed and transferred to other common cell formats to identify a fillable cell design and format‐dependent process improvement possibilities to enable faster processing.