CLG04P050L28 Datasheet, PDF (17/26 Pages) List of Unclassifed Manufacturers – Super Capacitors To Improve Power Performance.

Electrochemical Capacitors
The operating principle of the super capacitor is similar to that of a battery. Pairs of
electrodes are separated by an ionic conductive, yet electrically
insulating, separator (Fig. 2). When a super capacitor is charged, electronic charge
accumulates on the electrodes (conductive carbon) and ions (from the electrolyte) of
opposite charge approach the electronic charge.
This phenomenon is coined "the double layer phenomenon".
The distance between the electronic and the ionic charges is very small, roughly 1
nanometer, yet electronic tunneling does not occur.
Between charging and discharging, ions and electrons shift locations.
In the charged state a high concentration of ions will be located along the
electronically charged carbon surface (electrodes).
As the electrons flow through an external discharge circuit, slower moving ions will
shift away from the double layer. During EDLC cycling electrons and ions constantly
move in the capacitor, yet no chemical reaction occurs.
Therefore electrochemical capacitors can undergo millions of charge and
discharge cycles. This phenomenon which occurs with carbon electrodes of very high
surface area and a three-dimensional structure, leads to incredibly high capacitance
as compared to standard capacitors.
One can envision the model of the EDLC as two capacitors formed by the solid
(carbon) liquid (electrolyte) interphase separated by a conductive ionic
membrane. An equivalent electronic model is two capacitors in a series
connection (Fig. 3) where Cdl is the capacitance of each electrode; Rp is the
parallel resistance to the electrode, Rs is the resistance of the separator.
We conclude that the energy density of electrochemical capacitors is higher than that
of electrolytic capacitors, and therefore they have applicability for systems with lower
frequency requirements.
Current Collector
Anode
Separator
Cathode
Fig. 2
Fig. 3
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Revision: 21-3-10
Subject to change without notice