Decoupling elasticity and electrical conductivity of carbon-black gels filled with insulating non-Brownian grains

The interest in slurries formed by granular filler dispersed in colloidal gel is largely driven by the relevance to batteries, and the recent discovery of flow-switched bistability. This study extends previous investigations to make progress on elucidating the physics of such slurries. Surprisingly, the electrical and mechanical properties of the slurries can be either coupled or decoupled, depending on the conductive properties of the granular fillers. The different coordination numbers required for network rigidity and electrical percolation provide a key to understanding the decoupling, and important insight for optimizing the mixing and processing of industrial slurries.