Scanning porosimetry for characterization of porous electrode structures

A scanning technique has been developed to allow the porous microstructures and pore size distributions within porous electrodes to be directly unaged. The measurements use a piezoelectric-driven scanning probe similar to that used in scanning tunneling microscopy. The probe can map the conductivity through cross sections of porous electrodes, thus recognizing pores by their lack of high conductivity. By fitting the probe with a force gauge, it can simultaneously measure the topography of the surface. This technique can provide high-resolution (to 0.1 micron) images of the cross-section, or alternatively by scanning large numbers of pores it can provide pore-size distributions in localized regions of the electrode structure. Examples are provided of the types of electrode features that can be evaluated using this technique.