A Hybrid Electrochemical Supercapacitor Based on a 5 V Li-Ion Battery Cathode and Active Carbon

Supercapacitors coupled with batteries and fuel cells are considered promising midterm and long-term solutions for low- and zeroemission transport vehicles by providing the power peaks for startstop, acceleration, and recovering the breaking energy. Nowadays, much research on the electrochemical capacitors aim to increase power and energy density as well as lower fabrication costs and at the same time focus on making environmentally friendly materials. Compared with the traditional electrochemical double-layer capacitor EDLC, the hybrid electrochemical supercapacitor which relies on two different electrode materials shows a higher power density and a corresponding cycle life. This was recently reported by Telcordia Technologies with a new device named nonaquous asymmetric hybrid electrochemical supercapacitor HBEC with an intercalation compound Li4Ti5O12 which was used as the negative material and active carbon which was used as the positive material. 1 The new