Supercapacitors (SCs) have emerged as a promising high-power energy storage solution, playing a vital role in the transition from fossil fuels to sustainable energy sources. Recent experimental efforts to increase SC capacitance have focused on 3D-printing electrodes with tailored pore-size distributions. However, optimal electrode design principles based on ion transport in these complex porous geometries remain unclear.
In this study, we present a novel theoretical framework for electric-double-layer charging in porous media, accounting for arbitrary double-layer thickness. We derive an equivalent circuit representation of the governing equations and boundary conditions by performing cross-sectional averages, which enables us to determine the effective form of Kirchhoff's laws. Our one-dimensional axial transport model provides a significant improvement in computational efficiency over recently proposed semi-empirical models. We demonstrate the effects of tortuosity, average pore size, and polydispersity on the charging timescale of a network of pores. Our results suggest that pore configuration can be used to optimize the charging timescale of the system, even for a given pore-size distribution.
Relevant publications:
Henrique, Zuk, Gupta - Soft Matter 2022
Henrique, Zuk, Gupta - Electrochimica Acta 2022
Henrique, Zuk, Gupta - under preparation
Jarvey, Henrique, Gupta - Journal of Electrochemical Society 2022
