Why carbon monoliths are better supercapacitor electrodes than compacted pellets

Abstract

Cylindrical carbon monoliths (7 mm in diameter and 3.9 mm in height) with a microporous structure and compacted pellets derived from the monoliths with the same mass and similar geometric dimensions (6 mm in diameter and 3.2 mm in height) are studied as electrodes in two-electrode supercapacitor cells. The monolith cell shows better electrochemical behavior than the pellet cell, as deduced from its higher capacitance, lower resistance, and shorter response time. The specific capacitance of carbon in monoliths (150 F g-1) is compared to that in pellets (123 F g-1) and discussed. © 2010 The Electrochemical Society.