A novel electrode production process, based on a minimal solvent content, is developed for highly viscous water‐based graphite anodes, using a solid mass content of 50% or more compared to conventionally processed anodes. The electrode paste is prepared by mixing the solids with solvent inside of a twin‐screw extruder. Afterward, the extrudate is cut with a strand pelletizer to granules. By inserting the granules into the gap of a two‐roller calender, the current collector foil is coated directly. It is shown that the highly viscous pastes are capable of extended storage stability over several weeks, whereby a temporal and local decoupling of paste preparation and electrode manufacturing can be realized. To enable this innovative electrode processing, a combined development incorporating a selection of new anode binder materials, machinery design, and process parameters has been essential due to strong material‐process interaction, as known in the field of battery electrode production. Because the binder is exposed to greater shear stresses and a short duration time during extrusion mixing, the selection of novel anode binder materials is particularly important. This then needs to be combined with machine design and process parameter optimization, in order to establish this innovative electrode processing method.

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To improve the sustainability of large‐scale battery production, it is important to find affordable, energy‐efficient processing strategies. Additionally, to achieve electrochemical performances with good rate capability and cycling stability, it is important to understand the link between the processing strategy and the resulting anode morphology. Herein, a novel, low‐solvent, extrusion‐based strategy is employed for the production of graphite anodes. Furthermore, a comparative analysis is conducted between semi‐dry processed electrodes and conventionally manufactured anodes, focusing on structural parameters such as parameter distribution, ionic resistances, and rate capability. Besides, various screw configurations are employed during the semi‐dry process, and it is observed that higher energy input during mixing resulted in an increase in the surface area of the anode. Moreover, it is noted that an increased surface area correlated with enhanced rate capability during cycling. This finding highlights the advantages of employing low‐solvent, extrusion‐based processing methods. Nevertheless, excessively high surface areas lead to an increase in the electrolyte/electrode interface area, resulting in the formation of an undesirable solid–electrolyte interphase that hampers discharge capacity and cycling stability. Hence, it is crucial to strike a balance between the electrode's microstructure, including particle structures, and its electrochemical performance.

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