The process chain of electrode production includes calendering as a crucial process step to enhance the volumetric energy density as well as to influence the particle-pore-structure and simultaneously the mechanical and electrochemical properties of the electrode coating. A further way to improve the volumetric energy density is the usage of other materials with higher specific capacity, such as silicon instead of graphite as the active material for anodes. In this study, both opportunities, calendering and using silicon-containing composites, are combined to investigate the relations between material, process and performance. The applied line loads for the compaction are correlated with the silicon mass fraction and lead to a silicon-dependent mathematical model to estimate further line loads for silicon-graphite-composite electrodes. On the basis of established analyzing methods for adhesion strength and deformation behavior, it is shown that with increasing silicon content, the elastic deformation of the electrode coating rises. In addition, the overall porosity of the electrodes is less affected by silicon than the pore size distribution compared to graphite electrodes. Furthermore, the electrical conductivity decreases at higher silicon contents independent of coating density. Moreover, the long-term electrochemical stability deteriorates with increasing silicon content and coating density.

Binders are one of the essential components in lithium‐ion battery electrodes. Developments are focusing on high‐capacity anodes in particular, which place special requirements on the water‐based binder system, depending on material composition. Typically, the binders used are carboxymethyl cellulose (CMC) in combination with styrene butadiene rubber, but more environmentally friendly binders such as alginates (ALG) are also gaining importance. While many studies have addressed the synthesis and chemical interactions of these binders, most of them refer only to the material level and do not consider scalable manufacturing processes of the anodes. Moreover, the influence of binders on electrode structure and residual moisture is usually not, or insufficiently, considered. Accordingly, this study addresses the influence of CMC and ALG with different polymer structures (degree of substitution; M‐/G‐ratio) and molecular masses on processability, electrode structure, and performance. The findings suggest that different rheological properties (slurry) and electrode structures are produced, depending on the polymer type (CMC/ALG), and that both polymer type and electrode structure significantly influence residual moisture and adhesion strength. The electrochemical analysis is performed in coin full‐cells. From this, recommended actions for binder material development as well as knowledge‐based production processes for these anode material systems can be developed.

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