The Composite Supercapacitor

Inspired by the design of composite materials, we propose a new composite supercapacitor that comprises an integrated cell with high-power- and high-energy-related electrode materials. The composite electrochemical double-layer capacitor (EDLC) is the equivalent circuit of a high-power EDLC of power P-1 and energy E-1 and a high-energy EDLC of power P-2 and energy E-2 connected in parallel. A methodology is proposed and validated in this study for the design of an application-specific composite supercapacitor of power P and energy E with P-1/E-1>P/E>P-2/E-2. The methodology was tested successfully in medium- and large-sized application-specific composite supercapacitors, which were fabricated in the form of pouch cells using an organic electrolyte. The application-specific composite supercapacitors offered weight reductions of 40-60% compared with supercapacitors based on the high-power- or on high-energy-related electrode materials only.