A capacitor is a passive electronic component that stores electrical energy in an electrostatic field. This is unlike a battery, which stores energy in a chemical form. Capacitors are formed from two conducting plates separated by an insulator. The amount of capacitance is proportional to the surface areas of the plates, and inversely proportional to the separation between the plates. Nanomaterial supercapacitors use nanomaterials, which dramatically increases the surface area and the amount of energy that can be stored.