Output Current Characteristics of Different Density Graphite Cathodes for an Al-Cl₂ Cell in an 1-ethyl-3-methylimidazolium Chloride-aluminum Chloride Mixture Ionic Liquid

Abstract

To enhance three phase interfaces on graphite cathodes in an Al-Cl 2 cell, graphite cathodes with different densities (1.27, 1.32, 1.40, 1.57, and 2.00 gcm ) were evaluated in an 1-ethyl-3-methylimidazolium chloride -AlCl 3 mixture ionic liquid electrolyte at 313 K. The relation between current and cell voltage or power and current of the 1.27 gcm −3 graphite cathode showed the best performance among the graphite materials with 5 graphite densities in the cathodes investigated here. Surface profiles of the graphite by mercury intrusion porosimetry suggested that there are effective pore diameters for penetration of the electrolyte, lower density graphite has more pores on the surface than graphite with higher densities.