A supercapacitor is also known as a two-layer ultracapacitor or electrolytic capacitor. This is a type of capacitor that can store a large amount of energy, usually 10 to 100 times more energy compared to electrolytic capacitors.
Disassembling a supercapacitor
How does a supercapacitor work?
Supercapacitors use two different mechanisms to store electricity, electrostatic capacity based on electric double layer and pseudocapacity electrochemical. This means that supercapacitors combines the properties of capacitors and electric batteries in one device.
Supercapacitors consist of two electrodes, an electrolyte, a separating membrane, and their performance differs depending on the characteristics of the materials used. They do not work on the basis of chemical reactions, as in the case of conventional batteries, but on the basis of generation of electrostatic fields. These capacitors are polarized, so they must be connected correctly, as must the electrolytic capacitors.
Disadvantages of using supercapacitors
The main impediments to using supercapacitors are high cost and low energy density what characterizes these devices. Compared to regular Li-ion batteries, current supercapacitors cannot store a large amount of electricity and cannot maintain it for too long.
For this reason, supercapacitors, in their current form, cannot provide a long-term electricity charge for electric vehicles.
Where are supercapacitors used?
Supercapacitors are used in applications that require many fast loading / unloading cycles, rather than compact long-term energy storage - in cars, buses, trains, cranes and elevators, where they are used for regenerative braking, short-term energy storage or burst energy delivery. Smaller units are used as a random access memory (SRAM) power reserve.
The internal structure of the supercapacitor
The electrolyte forms a conductive ionic bond between the two electrodes, which distinguishes them from conventional electrolytic capacitors in which there is always a dielectric layer and the so-called electrolyte, for example, MnO2 or conductive polymer, is actually part of the second electrode. (cathode, or more correctly the positive electrode). Supercapacitors are polarized by design with asymmetric electrodes or, for symmetrical electrodes, by a potential applied during manufacturing.
Top 12 supercapacitor manufacturers
- Cellergy (USA)
- Ioxus (USA)
- Maxwell Technologies (USA)
- Murata Manufacturing (Japan)
- Nanoramic Laboratories (USA)
- Nec Tokin (Japan)
- Nippon Chemi-Con (Japan)
- Panasonic (Japan)
- Paper Battery Company (USA)
- Skeleton Technologies (Estonia)
- Yunasko (UK)
- ZapGo (UK)