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SuperCapacitors? What Are They?SuperCapacitors? How Do They Work?
The Ultracapacitor has 2 plates inside that charge according to the voltage applied, and store this charge as an electric field between the plates. Each plate has an equal and opposite charge depending on the polarity, if charged the capacitor can hold it's charge indefinitely until discharged by connection to an external load, like an electric motor... This is like the charge that builds up in your body on dry days, and gives you a shock when touching a doorknob etc... The capacitor has been around for a long time, since the early days of electronics... The super capacitor has been around for a long time too, and it has been researched and studied thoroughly enough to make it a commercial reality... A regular capacitor contains two plates and sandwiched between them is an electrolyte layer, but an ultracapacitor uses some technology taken from battery technology too... The electrodes inside them are made of materials that come from battery technology to increase the surface area like activated carbon and nanotubes, and other such hi tech materials... And because the voltage of a capacitor built like this is limited like a battery cell, the choice of voltages is limited to 1 or 2.5 volts. Meaning to get a large voltage output, they must be connected in series, or a string of them to increase the voltage, also then balancing of these voltages is is required, so that no capacitor is overcharged, this is done using a circuit that controls this.. Now the uses of capacitors as power supplies in vehicles is at the moment limited, but the promise of a fast charging high capacity unit is still there.. At the moment, most of the electric cars out there have lithium ion battery packs and some even use lead acid, mainly because of cost.. But who knows, if the supercap can be brought to commercial fruition, it could be the answer that many Electric car manufacturers are looking for...
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