I have manufactured some capacitors with silica as dielectric and I have measured them with an impedance analyzer, the Nyquists I was able to model them with the radle circuit. By plotting the normalized active and reactive powers for the complex power as a function of the frequency I have observed that they intersect at one point, even at one of the capacitors it crosses at two points. I have read in supercapacitor studies that the crossing of normalized powers is attributed to dielectric relaxation, but I do not completely understand what it means and why this happens with my capacitors in which I do not use any electrolyte.
Dielectric relaxation is related to the flow of charge and relaxation occurs when the recombination rate is slower than the generation rate of charge. This happens when charge gets slowed down by the resistance of the material.
It is not only an electrolyte that generates dielectric behaviour, but the fact that two plates are separated by a material. The silica is simply silicon dioxide which is a chemical compound that has charges.
Thanks your reponds Michael. Then this is relates to the formation of space charge. I have read that the relaxation time is the time in which one moves from a resistive to a capacitive behavior. But if there is another time of relaxation. What physical or chemical meaning would there be two relaxation times?
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