The first development step for a supercapacitor manufacturer is to make his choice between the different technologies and the different design types available: aqueous, organic, stack, winding, for example. The choice is mainly driven by the performances, the manufacturability and the costs. In this paragraph a survey of the main functions required from the different component parts has been described. A focus on the particular case of the commercial technology based on activated carbon and organic electrolyte has been treated.
From a conceptual point of view, the supercapacitor cell may be considered as an assembly of three main parts:
- the active part consisting of the electrodes and the separator
- the electrolyte impregnant
- the packaging.
The supercapacitor active part is made in most of the case of two identical electrodes. There is a spacer between the electrodes, the separator, which function is to provide an electronic insulation between the electrodes, while leaving the ions moving through its porosity to insure the ionic conduction. The active part is impregnated with an electrolyte made of a solvent containing a disassociated salt and is closed in a tight package [i].
[i] Yoshida A, Imoto K, Yoneda H, Nishino A. An electric double-layer capacitor with high capacitance and low resistance, IEEE Transactions on components, hybrids, and manufacturing technology 1992;15(1);133-8.