What is a supercapacitor

What is a supercapacitor

Supercapacitors, also known as EDLC (Electric Double Layer Capacitors), differ from ordinary capacitors in that they can store a large amount of energy. A basic capacitor typically consists of two metal plates separated by an insulator (such as air or plastic film). During charging, electrons accumulate on one conductor and leave another conductor. One party gains a negative charge while the other establishes a positive charge. Insulators interfere with the natural pulling of negative charges towards positive charges, and this tension generates an electric field. Once electrons are given a path to the other side, discharge occurs.

The supercapacitor also includes two metal plates coated only with a porous material called activated carbon. Immerse them in an electrolyte made of positive and negative ions dissolved in the solvent. One board is positive, and the other board is negative. During charging, ions from the electrolyte accumulate on the surface of each carbon coated plate. Supercapacitors also store energy in an electric field formed between two particles with opposite charges, where only they have an electrolyte where an equal number of positive and negative ions are uniformly dispersed. Therefore, during charging, each electrode ultimately has two layers of charge coating (double layer).

Batteries and supercapacitors

Unlike capacitors and supercapacitors, batteries store energy in chemical reactions. In this way, ions are inserted into the atomic structure of the electrode instead of adhering to the electrode like supercapacitors. This allows supercapacitors (which store energy without chemical reactions) to charge and discharge faster than batteries. Due to the fact that supercapacitors do not suffer the same wear and tear as batteries based on chemical reactions, they can withstand hundreds of thousands of charging and discharging cycles.

Compared with ordinary capacitors, supercapacitors have high energy storage capacity, but they still lag behind batteries in this area. Supercapacitors are usually more expensive than batteries. Technically speaking, supercapacitors can be used to replace phone batteries, resulting in faster charging speeds. Alas, it won't keep charging for a long time. However, supercapacitors are highly effective in receiving or providing sudden energy surges, making them suitable companions for batteries. Main energy sources such as internal combustion engines, fuel cells, and batteries serve well as continuous sources of low power, but due to their slow discharge and recharge, they cannot effectively handle peak power demands or regain energy. Supercapacitors provide rapid bursts of energy during peak power demand, then quickly store energy and capture excess power that would otherwise be lost. In the example of an electric vehicle, a supercapacitor can provide the required acceleration power, while the battery provides range and charges the supercapacitor between surges.