Performance of Electric Double-Layer Capacitor with Vertically Aligned MWCNT Sheet Electrodes Prepared by Transfer Methodology

Abstract

A variety of vertically aligned multiwalled carbon nanotube (MWCNT) electrodes, which maintain their original morphology prepared by a chemical vapor deposition technique, has been successfully fabricated by a transfer methodology from a seedbed substrate to a current collector. No ohmic potential drop on a galvanostatic discharge was observed for an electric double-layer capacitor (EDLC) containing electrodes with not only a MWCNT length of 10μm but also a length of 200μm . Cyclic voltammograms for electrodes with MWCNT lengths of both 10 and 200μm showed no distorted current response, even at an extremely high scan rate of 50Vnormals−1 . These results demonstrate that the present EDLC with the MWCNT electrodes can provide an outstanding rate capability irrespective of the MWCNT length when prepared by our transfer methodology. To find suitable MWCNT electrodes for high-performance EDLCs, we investigated several relationships among the specific capacitances of aligned MWCNT electrodes and their major properties, i.e., their gravimetric and volumetric capacitances, length, diameter, and number density.

Development of High Performance Electrochemical Capacitor: A Systematic Review of Electrode Fabrication Technique Based on Different Carbon Materials

“…Moreover, CV at an extremely high scan rate of 50 V s −1 exhibited rapidly responsive charge-discharge currents without a significant distortion for either MWCNT electrode. 99 Furthermore, Honda et al successfully prepared vertically aligned double-walled CNT (DWCNT) sheet by transfer technique from a Si substrate to an Al sheet as a current collector for application to a high-performance electrode for an EDLC. The vertically aligned DWCNT was grown using a thermal catalytic CVD technique.…”

Modern Theories of Carbon‐Based Electrochemical Capacitors

“…Recently, several experiments were performed on carbon onions [24,97], vertically aligned CNT arrays [98,99], and carbon nanofibers [23], providing results that show superior rate capabilities of exohedral supercapacitors. General discussions in the literature on the pores of these carbon structures refer to the voids between carbon particles.…”

Manufacturing of Electric Double‐Layer Capacitors Using Carbon Nanocoils and Evaluation of their Specific Capacitances at a High Scan Rate

“…To solve the above-mentioned problems, there are number of reports that improve the active electrode materials by the pulverization and chemical treatments [1,2], use activated carbon (AC) derived from tree resin as the active electrode material [3][4][5], and use carbon nanomaterials other than AC [6][7][8][9][10]. Above all other nanomaterials, carbon nanotubes (CNTs) are expected for the active electrode material in EDLCs.…”