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The post‐drying of electrodes and separators for lithium‐ion batteries just before cell assembly aims at reducing the water content in the cells below a critical value. This is important as the remaining water can lead to cell degradation and thus cause a safety risk. In addition, it can impede the formation of an effective solid electrolyte interface. Nevertheless, the post‐drying of lithium‐ion battery electrodes and separators is still poorly investigated. Considering this, three different post‐drying procedures are investigated on pouch cells and compared with the non‐post‐dried state. The remaining water contents are measured via coulometric Karl Fischer Titration and correlated to the resulting electrochemical performance. Surprisingly, the most intensely post‐dried cells show the worst electrochemical performance despite reaching the lowest water content. In contrast, the mildest post‐dried cells, which show the highest water content, achieve the best electrochemical performance. Further analyses show that extreme post‐drying can cause irreparable damages within the electrode structures. Therefore, a good electrochemical performance is not only guaranteed by low remaining water content but also, in particular, by gentle post‐drying.

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Graphite electrodes, containing 8 wt% binder and 4 wt% conductive additives, manufactured from one batch of a continuous coating and drying process in technical scale, are investigated under variation of specific compression rates. The influence of the calendering process is studied in terms of surface morphology, mechanical, structural and electrochemical properties. Graphite electrodes are found to be sensitive to compaction and a compression rate of 10 % was identified to be beneficial to long term cycling stability, while the impact on power performance was found not to be affected to a high extent. The change of pore structure for specific pore size ranges and the deformation of active material are identified to be crucial factors negatively influencing electrochemical performance. Plastic and elastic deformation energies of the electrode coating layer are derived by nanoindentation. This method is suitable to quantify the electrodes’ mechanics and undergoing particle deformation caused by calendering.

In the present work two of the various drying process parameters, air temperature and nozzle speed, are studied and their influence on the electrode’s physical properties is examined by different mechanical and electrical analyzes. It was found that elasticity, electrical volume resistivity and adhesion strength of the coating to the substrate, can be dependent on process parameters used for manufacturing. These properties are also influenced by the electrode’s mass loading and its recipe, as the total solvent content and therefore the drying time plays an important role. Assuming binder demixing during drying allows explaining the results, since evaporating solvent induces a temperature dependent compensational flow of solvent and solved binder. If immobilization occurs faster than compensational flow can cause significant demixing, no binder gradient emerges. The driving force counteracts the drying time, but increases demixing, so that optimum drying conditions exist for each mass loading and solid content.