Most of the pseudocapacitor materials do not show the perfect rectangular shape CV; but during the calculation of the specific capacitance the area under the CV curve is used for the calculation of the specific capacitance. The attached file corresponds one such examples, where fig. 1 corresponds to the area under the CV; in fig. 2 & 3, the area under the curve corresponds to the charge stored and released during charging and discharging process respectively. We see the area of fig. 2 and 3 are much higher than the area under the CV (fig. 1); therefore, my question is How far it is correct to consider the area under a non rectangular CV for for capacitance measurement. Should we consider the individual charging and discharging process while calculating the specific capacitance or or only the total area under the CV although the CV is non rectangular in shape?
Hi Dey, from your figure I see CV is actually rectangular. But it is slanted because of the series resistance. You may add a conductive additive to make this CV flat. If you really had redox materials/faradaic storage, you should have had obvious peaks.
Also: Psuedocapacitors show almost perfect rectangular CV. If it is not showing supercapacitor like behaviour, then it is not a pseudocapacitor, it could be Hybrid-capacitor/super-capa-battery -supercapacitor-Battery hybrid
For the conductive additive you may refer to :
Article Self-assembled fullerene additives for boosting capacity of ...
(note: in this article, the working window used for CV is 0.5V only)
For CV analysis and description of actual psuedocapacitor:
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