Starch as a Green Binder for the Formulation of Conducting Glue in Supercapacitors

Abstract

This work describes the use of commercially available starch as a binder for the preparation of conductive glue and electrode materials. It is demonstrated that starch can be successfully implemented as a binder in energy storage systems with non-aqueous electrolytes. These devices are characterized by a stable cycle life (for 50,000 cycles) at a nominal voltage of 2.5 V. Moreover, the use of starch-based conductive glue improves the electrochemical performance, especially reducing the internal resistance of the device. Starch-bound electrodes display lower equivalent distributed resistance (EDR) values than electrodes using carboxymethylcellulose (CMC) as the binder. This is due to the noticeably lower pore clogging by starch. An electric double-layer capacitor (EDLC) in organic electrolyte (1 mol L−1 TEABF4 in ACN) at a nominal voltage of 2.5 V can reach a specific power and energy of 100 kW kg−1 and 12 Wh kg −1, respectively. This study shows that starch-based conductive glues and electrode materials can be incorporated in EDLC systems.