Nerd Night - Spring 2020
April 22, 2020
Oral Presentation
Title:
Effect of Shear Rate and Drying Speed of Li-Ion Battery Processing
Abstract:
Processing conditions of battery slurries into electrodes are known to affect final battery performance. However, there is a lack of fundamental understanding of how the relationships between processing conditions, slurry microstructure, and film microstructure affect electrode performance. This study determines the effects of coating shear rate and drying temperature on battery electrode performance via discharge capacity. We use rheological measurements and energy dispersive x-ray spectroscopy (EDS) to correlate slurry and electrode microstructures to trends in discharge capacity. The radial distribution function is used to quantify differences in electrode microstructure. More specifically, we show that the correlation between carbon and active material EDS detections to be the most relevant in understanding battery performance. Electrodes with both short- and long-range carbon/active material order have the highest discharge capacities. This microstructure can be obtained through high shear rates, which induce better carbon dispersion via strong hydrodynamic forces, or through high temperature drying by preventing unwanted time-dependent structural changes after flow cessation. This analysis provides concrete evidence for the importance of both short-range and long-range contacts between conductive additive and active material on battery performance
April 22, 2020
Oral Presentation
Title:
Effect of Shear Rate and Drying Speed of Li-Ion Battery Processing
Abstract:
Processing conditions of battery slurries into electrodes are known to affect final battery performance. However, there is a lack of fundamental understanding of how the relationships between processing conditions, slurry microstructure, and film microstructure affect electrode performance. This study determines the effects of coating shear rate and drying temperature on battery electrode performance via discharge capacity. We use rheological measurements and energy dispersive x-ray spectroscopy (EDS) to correlate slurry and electrode microstructures to trends in discharge capacity. The radial distribution function is used to quantify differences in electrode microstructure. More specifically, we show that the correlation between carbon and active material EDS detections to be the most relevant in understanding battery performance. Electrodes with both short- and long-range carbon/active material order have the highest discharge capacities. This microstructure can be obtained through high shear rates, which induce better carbon dispersion via strong hydrodynamic forces, or through high temperature drying by preventing unwanted time-dependent structural changes after flow cessation. This analysis provides concrete evidence for the importance of both short-range and long-range contacts between conductive additive and active material on battery performance