Comparative numerical analysis of mixing characteristics for electrode slurries in static mixers

The present study examines the flow and mixing characteristics of anode slurries for lithium-ion batteries within static mixers. The thixotropic nature of a model anode slurry was measured with a rheometer and condensed into a constitutive equation based on the two-parameters structural kinetics model where two structure parameters (λ1 and λ2) represent microstructure organized by active material and polymeric binder, respectively. The flow fields and structure parameter distribution of the model anode slurry in three distinct static mixers, namely the Kenics mixer, barrier-embedded partitioned pipe mixer (BPPM), and the Sulzer SMX mixer, were obtained using the computational fluid dynamics simulations. The distribution of structure parameters, which serve as a metric for evaluating dispersive mixing performance, revealed that the dispersive mixing performance can be ranked in the following order: Sulzer SMX, Kenics, and BPPM mixer. However, all these mixers were still found to be insufficient in effectively mixing the microstructure associated with the polymeric binder. In the case of the distributive mixing performance, which was quantitatively investigated by the concentration distribution of tracer particles, the performance followed same sequence as the dispersive mixing performance, while the SMX is shown to be the worst option in terms of energy consumption.