@Pravin Wadekar

The specific capacitance values derived from CV and GCD should match if the conditions of experiments are comparable. Particularly the current load (or mass normalised current, A/g) needs to be the same or comparable in the two methods. However, if the current load differs in the two methods, the results can be different. Usually, the specific capacitance becomes smaller if the current load increases. The cause of the variation is mostly related to the electrode kinetics and polarisations due to reaction and/or material resistance.

For the two- and three-electrode measurements, the results can only be converted meaningfully when the two-electrode cell is symetrical, i.e. both the positrode and negatrode in the two-electrode cell are made from the same material as that used to make the working electrode in the three-electrode cell. If so, the cell capacitance of the two-electrode cell would be equal to a quarter of that of the working electrode in the three-electrode cell.

The specific capacitance can be calculated using CV using following formula:

C= Idv/dV S M

where, Idv is integrated area under CV curve

dV is difference in potential (V)

m is mass of active material (g)

S is scan rate

Thanks Pramod kalambate,

Is this same for 2 electrode and 3 electrode or i have to multiply by 4 for 2 electrode?

how to measure integrated area under the curve?

go through this

https://www.researchgate.net/post/How_can_we_measure_the_specific_capacitance_in_F_g_using_cyclic_voltammetry

Thank you so much for your answers.

i have done the calculations by both i.e. CV rectangular graph and GCD, but values are not same in both. is there any relation in cyclic volammetry values and GCD values?

@Pravin Wadekar

The specific capacitance values derived from CV and GCD should match if the conditions of experiments are comparable. Particularly the current load (or mass normalised current, A/g) needs to be the same or comparable in the two methods. However, if the current load differs in the two methods, the results can be different. Usually, the specific capacitance becomes smaller if the current load increases. The cause of the variation is mostly related to the electrode kinetics and polarisations due to reaction and/or material resistance.

For the two- and three-electrode measurements, the results can only be converted meaningfully when the two-electrode cell is symetrical, i.e. both the positrode and negatrode in the two-electrode cell are made from the same material as that used to make the working electrode in the three-electrode cell. If so, the cell capacitance of the two-electrode cell would be equal to a quarter of that of the working electrode in the three-electrode cell.