Supercapacitors — An alternative electrical energy storage device

Abstract

In the last time, the power supplies issues of electronic circuits had become an important issues, especially for mobile devices. The use of classical or Li-ion batteries in the industry, mainly utilized in storage systems, is not a viable solution because these devices, after 2–3 years, lose their ability to store electricity and the materials employed are polluting, even banned in some countries. The European Union regulation like RoHS 1 and RoHS represent sometimes a real bottleneck. Fortunately in the last time on the market more and more are present electronic passive components like supercapacitors. The Supercapacitors (Electrochemical Double Layer Capacitors — EDLCs) are the promising solution for the future. They do not contain lead or other polluting materials on a side and on an other side they are able to storage large quantity of electrical charge. EDLCs have a very long lifespan (> 106 unloading cycles) and very small internal resistance, which allows charging and discharging at very high currents (hundreds of A). Also, another advantage of using EDLCs battery systems in power structures is a decrease of the weight of the entire system. We have simulated and analysed the behaviour of a 100F/12V EDLC system by connecting 6 supercapacitors (600F/2.5V) in series. In this context, using an EDLC system, we have obtained interesting results after the primary power source has been disconnected. The proposed model is in the R&D phase, but the test results are promising. EDLC is a very viable solution for use in a hybrid electric system such as a UPS or electric car.