An Introductory View About Supercapacitors

Fossil fuels have been the primary source of energy for hundreds of years. With growing energy demands, this source not only depleting but also contributing to various environmental problems that have a serious impact on the health of common people. Consequently, researchers all over the world have shifted toward a renewable source of energy like sunlight, wind, and waste heat for generating energy without emitting harmful substances (CO2) into the environment in order to account for all the current issues. Further, without having efficient energy storage systems, harvesting energy from such sources will not be enough to fix the issue. Due to their high energy efficiency and potential for sustainable power generation, technology and materials for electrochemical energy storage have attracted a great attention in the field of energy storage. Supercapacitors are the most appealing alternative to batteries and fuel cells because of their mechanism, which takes advantage of traditional capacitors and batteries as well as bridges the energy gap between them. Owing to various advantageous properties such as high power density, high rate capability, long-lasting and stable cyclic performance, fast charging-discharging ability, and environmental friendliness, supercapacitors have been used in significant energy storage platforms such as electronic communications, aerospace, and electric transportation. Electric double-layer capacitance (EDLC) and pseudocapacitance are the two charge storage processes used by supercapacitors. In the pseudocapacitive process, a faradaic redox reaction takes place, whereas, in the EDLC, a double layer of charge forms at the electrode–electrolyte interface. Supercapacitors are utilized in many applications and have been theoretically proven to be a source of sustainable energy storage, but their performance still has to be improved in order to keep up with the growing energy demands of society today. The main aim of this chapter is to provide an introductory idea about various aspects of supercapacitor.