ABSTRACT
Supercapacitors (SC), also known as electrochemical capacitors or ultracapacitors, are energy storage devices that have the same basic components than a battery: two electrodes, an electrolyte, and a separator. These devices are thought to cover the gap between traditional electrostatic capacitors with high specific power (up to 10,000 kW/kg) and low specific energy (up to 0.08 Wh/kg) [1], and batteries with higher specific energy (20 -200 Wh/kg) [2]. Most of commercial available SC are constructed with a symmetric configuration using high-surface-area carbons as the active electrode material, and an organic or non-aqueous electrolyte. The main disadvantages of these SC are the electrolyte
toxicity and their low specific energy (5 -10 Wh/Kg) [2, 3]. More recently, aqueous electrolytes and hybrid or asymmetric SC are being introduced slowly to the market in order to overcome these disadvantages, and move to a more environmentally friendly device (Cellergy Israel, Elton Super Capacitors, Inmatech).
