Energy in the Future series: What is the potential of Supercapacitors for energy storage and transfer?
Supercapacitors are energy-storing devices that use high surface area electrode materials (such as a carbon powder) and liquid electrolytes which act as dielectrics (electrical insulators). Supercapacitors can be broken down into three main categories: double-layer capacitors (store charge electrostatically), pseudocapacitors (store charge electrochemically), and hybrid capacitors, which are a combination of double-layer capacitors and pseudocapacitors. Compared to conventional capacitors, supercapacitors have a higher capacitance (electric charge-storing capability. When compared to batteries, supercapacitors have a higher power density, lower energy density and a longer cycle life.