It is not clear (to me) what as “GCD study” is in this (unspecified) context.

Typically if you want to use off-the-shelf equipment then you need to write your own control software. For example you can do charge/discharge with a source/measure device (eg from Keithley) and use Labview code.

You want to use a Pine Instrument. From their website it looks like the Wavedriver 200 EIS Bipotentiostat can apply currents and both measure and apply voltages. (I have never seen one and I am not sure of its exact function.)

It is unclear if their Aftermath software gives the required control function.

This method would seem to give a constant current discharge (but you don’t explicitly specify what you need).