TA Instruments Rheo-Impedance Spectroscopy

Rheo-Impedance Spectroscopy offers powerful insights into microstructure of complex fluids such as battery electrode slurries, emulsions, paints, coatings, and more. Coupling dielectric impedance spectroscopy with the DHR’s rheology measurements empowers users to characterize shear-induced changes in sample microstructures under process-relevant conditions such as mixing, storage, and coating. Simultaneous precise measurements of viscosity, yield stress, viscoelasticity, and recovery deliver new insights connect flow properties to underlying changes in microstructure. Battery electrode slurry formulation and process development is guided by impedance spectroscopy. Initial impedance measurements performed without applied shear indicate the dispersion of conductive material in the slurry after mixing. Simultaneous impedance and rotational deformation directly measures shear-induced changes in the microstructure, replicating slurry coating conditions and enabling measurements of time-dependent recovery after shear. These new insights verify the electrically conductive network is maintained in the finished electrode and ensure successful battery performance.