Influence of dispersing by extrusion and calendering on the performance of lithium-ion battery electrodes

摘要

The present work focuses on the influence of the process steps dispersing by extrusion and calendering on the electrode characteristics, particularly on the structure of Carbon Black (CB)-binder-matrix, electrode resistance and pore structure, as well as the electrochemical performance in regard to rate capability and long term performance. This work wants to draw attention to the importance of a distinct process know-how and an in-depth product analysis regarding to the production of electrodes for lithium-ion batteries. Different effects of the dispersing and calendering step are discussed in context of present scientific knowledge. Furthermore, the distinct role of CB in the structure of electrodes is demonstrated. A different CB deagglomeration has a significant influence on the structure and performance of electrodes, while the formulation of electrodes remains constant. An important part is played by the CB surface to binder ratio, which varies with CB agglomeration state. On the other hand, the interaction of dispersing and calendering steps and their diverging impact on anodes and cathodes is illustrated. To summarize, this work should enable the reader to make decisions regarding the formulation of recipes and the processing of intermediates in electrode production and gain a better understanding of their structure.