Capacitors vs Supercapacitors
Capacitors are very useful components and are widely used in electronic and electrical circuits. Capacitor is a component capable of storing charges and thereby energy. A super-capacitor is a component capable of storing more charges than a normal capacitor. Both of these components have wide applications and are very useful in constructing complex circuits. Capacitors are used in fields such as electrical engineering, electronic engineering, computer designing, energy storage and various other fields. It is very important to have proper knowledge in the theories behind capacitors and super-capacitors in order to excel in such fields. In this article, we are going to discuss what capacitors and super-capacitors are, their applications, how capacitors and super-capacitors are made, different types of capacitors and super-capacitors, their similarities and finally differences between capacitors and super-capacitors.
Capacitors are components that are used to store charges. Capacitors are also known as condensers. Commercially used capacitors are made of two metal foils rolled into a cylinder with a dielectric medium in between them. The capacitance is the main property of a capacitor. The capacitance of an object is a measurement of the amount of charges that object can hold without discharging. Capacitance is a very important property in both electronics and electromagnetism. Capacitance is also defined as the ability to store energy in an electric field. For a capacitor, which has V voltage difference across the nodes and the maximum amount of charges that can be stored in that system is Q, the capacitance is Q/V, when all are measured in SI units. The unit of the capacitance is farad (F). However, it is inconvenient to use such a large unit. Therefore, most of the capacitance values are measured in nF, pF, µF and mF ranges. The energy stored in the capacitor is equal to (QV2)/2. This energy is equal to the work done on each and every charge by the system summed up. The capacitance of a system depends on the area of the capacitor plates, the distance between the capacitor plates, and the medium between the capacitor plates. The capacitance of a system can be increased by increasing the area, decreasing the gap or having a medium with higher dielectric permittivity.
Electric double layer capacitors or EDLCs are generally known as super-capacitors. Super-capacitors in general have a very high capacitance compared to normal capacitors. The capacitance of a super-capacitor is usually two or three orders of that of a normal capacitor. The main property that matters in a capacitor is the capacitance density or the energy density. This refers to the amount of charges that can be stored per unit mass.
What is the difference between Capacitors and Super-capacitors?
• Super-capacitors have a very high energy density than normal capacitors.
• Super-capacitors use two layers of the dielectric material separated by a very thin insulator surface as the dielectric medium, whereas normal capacitors use only a single layer of dielectric material.
• Normal capacitors are much cheaper than the super-capacitors in general.