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The targeted adjustment of carbon black (CB) particle size in electrode slurries is a key step in battery production. Based on the energy input and dispersion device, the resulting particle structure of CB differs significantly. Most frequently, especially in more recent publications, the median particle size was used to describe changes during dispersion. However, this value does not contain enough information to describe the dispersion progress of bimodally distributed particles sufficiently. In this short communication, a novel approach describing the dispersion progress of CB containing slurries is introduced. This method was developed utilizing the hierarchical structure and fragmentation behavior of CB. The Carbon Black Dispersion Index DICB allows quick and easy assessment of the dispersion progress by isolating the CB aggregates of the bimodal distribution. This value offers major benefits with regards to quality control and production monitoring. [ABSTRACT FROM AUTHOR]

The conductive network within a lithium-ion battery electrode is mainly influenced by the process parameters chosen for the dry mixing and wet dispersing step during the production of a coatable electrode slurry, consisting of well-defined components. This conductive network, which results from the electrode's microstructure, plays a major role for the resulting battery cell performance, especially for high performance and power applications. Notable differences can be observed in the subsequently manufactured electrodes due to process-related modifications in the carbon black agglomerate size; mechanical, electrical, and, thus, electrochemical properties are significantly changing with the process parameters set. To allow for a direct correlation of these properties with the electrode structure, a characteristic parameter to describe the carbon black structure in electrode coatings is developed. Based on mercury intrusion measurements, the internal porosity of carbon black particles was determined as a characteristic parameter for the conductive microstructure. For a wide variety of lithium-ion battery cathode samples, the carbon black porosity can be well related to important electrode properties. This underscores the relevance of this carbon black-based microstructure parameter for a knowledge-based process and product optimization. [Display omitted] • Carbon black porosity as a structural parameter for LIB is developed and proven. • Wet dispersion and dry mixing can be used to adjust the carbon black porosity. • Carbon black porosity determines C-rate performance in the form of an optimum curve. [ABSTRACT FROM AUTHOR]