Impact of CB dispersion on the performance of lithium-ion battery cathodes
Marcel Weber, Jessica Gerstenberg, Arno Kwade
Abstract
Lithium-ion battery electrode performance is heavily dependent on the carbon binder domain. Both, experimental and simulation studies have affirmed its substantial impact on electrode properties, yet a precise quantification remains challenging. This study uses a co-rotating twin-screw extruder to adjust the carbon binder domain by varying mixing intensity. Employing the Carbon Black Dispersion Index (DI CB ), we quantitatively evaluate changes in carbon black (CB) particle size and their impact on electrodes and cells. The results highlight the crucial role of CB dispersion in shaping the carbon binder domain. The correlation of the DI CB with electrode properties reveals an optimal dispersion intensity range, especially for rate capability and ionic resistance. Customizing the dispersion process using DICB led to a remarkable 26 % enhancement in specific discharge capacity at high C-rates. This research emphasizes DI CB 's significance in optimizing electrode performance and offers a novel approach to tailor the dispersion process for more efficient lithium-ion battery electrodes. Such tailored approaches hold promise for creating greener energy storage solutions, with implications for industrial applications, process scaling, and quality control procedures. • CB fragmentation is strategically adjusted in a twin screw extrusion device. • Rupture and erosion are major fragmentation mechanisms in battery slurries, with increasing solids content favoring erosion. • Strategically adjusting the carbon black fragmentation, enhances the electrical, mechanical and electrochemical properties. • The Carbon Black Dispersion Index is introduced as a promising quality measure in electrode production.