Connections Matter: On the Importance of Pore Percolation for Nanoporous Supercapacitors

Nanoporous supercapacitors play a key role in energy storage and thereby attract growing interest from the research community. Development of porous electrodes for supercapacitors is of the paramount importance, but their characterization still remains a challenge. Herein, we analyze two examples of the popular carbide-derived and activated carbon electrodes from the point of view of interpore connectivity and ion permeation. Due to limited percolation, the effective porosity, as seen by an ion, decreases with an increase in the ion size, which can reduce the stored energy density substantially. Our results highlight the importance of high quality well-percolated porous electrodes for supercapacitors and suggest that the interpore connectivity is an important characteristic to consider when optimizing the existing and developing new electrode materials.