Basic knowledge of supercapacitors

Basic knowledge of supercapacitors

Supercapacitors (sometimes referred to as SCs) are electrochemical devices that can quickly store and supply high-power electricity and perform large cycles (up to millions of cycles) without displaying performance degradation.

The simplest supercapacitor mainly consists of two electrodes and an electrolyte inserted into it. The charge is arranged at the electrode/electrolyte interface and there is no chemical redox process. Due to the limited physical processes involved in accumulation, materials must have a high surface area to accumulate a significant amount of charge.

Supercapacitor module

Supercapacitors are double-layer capacitors with very high capacity but low voltage limitations. Compared to capacitors, supercapacitors have a larger area for storing more charges, reach the Farad (F) range of capacitance, and store more energy than electrolytic capacitors. They have low leakage current and are suitable for many applications that can operate in the range of 1.8V to 2.5V. The lifespan of supercapacitors is 10-20 years, but after approximately 8-10 years, the capacity can be reduced from 100% to 80%.

Due to its low equivalent series resistance (ESR), supercapacitors can provide high load current and fast charging. Micro supercapacitors are MEMS like devices that can withstand repeated bending, making them suitable for flexible applications. This is an ideal choice for wearable devices and IoT applications. We are developing flexible solid-state micro supercapacitor glass, silicon, and paper substrates.

When voltage is applied to a supercapacitor, two separate charge layers are generated on the surface, with a spacing distance smaller than that of traditional capacitors. This is why supercapacitors are commonly referred to as double-layer capacitors or EDLCs.