Please help me to solve this GCD curve and calculate the capacitance
Is it fair to apply C= It/ mV equation to calculate the capacitance?
please comment your idea about my GCD graph.
Typically: yes, total charge passed over the change in voltage during which that charge is passed, but in your case, there is not enough information to calculate capacitance. Mostly because your behavior is not...normal for a capacitor. Are both the charge and discharge at a constant current? If so the behavior is not that of a pure capacitor (more like a battery, but not really that either). The step behavior on discharge looks a bit like an iR effect (e.g. spending 50 s at i then the rest of the time at 2*i) but it's really large.
I'd recommend EIS (maybe CV if you can't run EIS) since there seems to be more going on in your cell than just capacitance.
This does seem very battery-like behavior due to the plateaus during both charge and discharge. It is also strange on your 6.25 A/g curve that the potential increased slightly during the first discharge step.
I would definitely recommend studying the CV which should ideally be rectangular, though I assume will look redox-like.
Dear Yasun, I feel strange to see your charging capacity is very less compared to your discharge. Probably you have a very huge irreversible capacity if you working at very low potential where electrolyte decomposition is happening. Please check your electrolyte is stable in that region. Also make sure your charging/discharging current is same. As Jacob recommended, you may run an EIS to see the reason for the huge drop in the voltage, which can be either from ESR or from the very high irreversibility.
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