Understanding the Impact of Shear Control on Reproducible Production of Battery Electrodes at the Lab Scale

Electrode slurry coating is critical to battery manufacturing, with downstream production steps and battery performance dependent on the electrode cast quality. While commercial facilities use roll‐to‐roll coating to minimize processing times and ensure inter‐batch consistency, these techniques are not feasible for lab‐scale R&D owing to the high cost and large footprint of the infrastructure. As such, lab‐scale electrodes are typically prepared manually with minimal control over quality‐affecting parameters (i.e., blade speed and height), which can introduce interelectrode variability. This lack of reproducibility can cause issues with performance validation and repeatability across laboratories when developing new materials. Herein, we apply an automated casting system developed from 3D printer architecture to demonstrate how shear control during lab‐scale electrode casting enables consistent replication of quality metrics such as active material loading and capacity. By accurately modulating the blade speed during casting, variance in loading across a 100 cm 2 sheet was greatly reduced. Interelectrode coefficient of variation for loading was minimized to <7% when casting at 5.00 cm s −1 and 150 μm, in comparison to >15% when done manually. This work highlights the importance of maintaining control over electrode casting conditions to improve inter‐lab comparisons, generate reliable results, and support next‐generation battery material development.