STL files and data to support: Improvements in methods for measuring the volume conductivity of electrically conductive carbon powders
Kane, Seth; Ryan, Cecily; Warnat, Stephan (2021), STL files and data to support: Improvements in methods for measuring the volume conductivity of electrically conductive carbon powders, Dryad, Dataset, https://doi.org/10.5061/dryad.ht76hdrd1
Electrically conductive carbon powders are commonly used as filler materials in polymers to create electrically semi-conductive composite materials for use in battery electrodes and anti-static applications. Current methods for characterizing the conductivity of these powders use two pistons to compress the powders. Two-piston methods are known to underestimate conductivity. This study develops a guard-electrode method based on ASTM D257 to better characterize the bulk conductivity and impedance spectra of electrically conductive powders. The conductivity and impedance spectra of a highly conductive powder (copper powder) and a low conductivity powder (cellulose) were used to bound the conductivity of carbon black, graphite, and biochar. Powders were measured through a full range of compression with both the two-piston and the guard-electrode method. In all cases, measurements using the guard-electrode method have higher conductivity and lower impedance than the same powders measured using the two-piston method. The grain conductivity of the particles is obtained through fitting the relationship of conductivity versus packing fraction using the GEM equation. The guard-electrode method is shown to be more similar to established conductivity values as measured via a four-probe technique for copper and graphite then the two-piston method.
National Science Foundation