Interaction analysis between binder and particles in multiphase slurries.

A multiphase slurry for rechargeable lithium-ion batteries is prepared using an active material, a carbon conductive, a polymeric binder and a solvent, and its physicochemical characteristics is evaluated in this study. The polymer binder interacting with particles in the slurry plays a crucial role in constructing the internal configuration of slurry components. The internal structure and dispersion states of the slurry components, which affect battery fabrication processes such as coating and even determine the final performance of battery cells, are changed over time. Experimental measurements such as spectroscopic, rheological, morphological, and electrical tests are carried out. Morphological specimens are freeze-dried to fix the locations of the slurry components. The existence of a network structure (or flocculation) is verified by viscoelastic property measurements and morphological observations. Electrical properties of the slurry vary mainly depending on the dispersion state of the carbon conductive. In addition, the dispersity index is introduced as a new quantity representing the dispersion state of the slurry components.

Liquid slip on a nanostructured surface.

We explored a liquid slip, referred to as the Navier slip, at liquid-solid interface. Such a slip is provoked by the physicochemical features of the liquid-solid system. The goal of this study was to investigate the effect of a nanoengineered surface structure on liquid slip by fabricating the self-assembly structure of nano Zinc oxide (n-ZnO). We have also examined how the liquid-solid surface interaction controlled by hydrophobic chemical treatment affects the liquid slip. The findings showed that liquid slip increases with decreasing the characteristic length scales (e.g., channel height and depth), resulting in drag reduction. It was also found that dewetted (Cassie) state due to the generation of air gap developed by n-ZnO was more critical for the liquid slip than the minimization of interface interaction. The linear and nonlinear Navier slip models showed that liquid slip behavior is more obvious when increasing the nonlinearity. This study will contribute to understanding of the underlying physics behind fluid slip phenomena, such as the Navier slip for Newtonian liquids and Maxwell's slip for Newtonian gases.