Mechanochemical Processing of Natural Graphite under Different Atmospheres for Fabricating Electrodes Used in Electric Double-layer Capacitors

Abstract

This study focused on the mechanochemical processing of natural graphite using a planetary ball mill under different atmospheres and analyzing their influence on the electrochemical behaviors of the processed graphite materials in electric double-layer capacitors (EDLCs). Oxygen and/or nitrogen were incorporated in the carbon framework from the atmosphere used during milling. Specific surface areas of the pulverized graphite did not significantly depend on the employed atmosphere. These pulverized graphites processed under different atmospheres were evaluated as electrode materials for application in EDLCs with an organic electrolyte. All the pulverized graphites showed comparable capacitances independently of the used atmospheres. Considering the effect of post-thermal treatment of the pulverized graphite to remove oxygen surface functionalities, changes in the surface functionalities of pulverized graphites caused by ball milling did not significantly influence their applications as electrode materials in EDLCs.

Keywords

• electric double-layer capacitor
• pulverized graphite electrodes
• mechanochemical processing
• surface functionalities