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Techniques and Applications Manual
experiment potential limits. This will considerably reduce the noise level and increase the plot
quality.
3.2.2 CstV: Constant Voltage
The constant voltage (CstV) technique is especially dedicated to supercapacity testing. It is
designed to apply successively several voltage steps to the cell(s). Between each voltage step,
an open circuit voltage period can be added.
 Rest period
The rest period is an open circuit voltage period. Refer to the OCV description for more details.

Potential step with data recording conditions
Apply Ei = … V vs. Ref/Eoc/Ectrl/Emeas.
the potential step is defined vs. Ref the reference electrode potential or according to the previous open circuit potential (Eoc), controlled potential (Ectrl) or measured potential (Emeas).
for ti = … h … mn … s
sets the potential step duration.
Limits |I| to IMax = … pA/…/A
and |Q| < QM = ... fA.h/…/A.h/pC/…/kC.
Imin = … pA/…/A
curtails the step duration if the current or charge limit is reached. If the limit is reached, the
loop condition (go to Ns' for nc times), if set, is not used, and the program continues to the next
sequence (Ns + 1).
The |Q| value is the integral charge for the current sequence. This value is not reset if there
is a loop on the same sequence (Ns' = Ns).
0 values disable the tests.
Record I every dIp = … pA/…/A, dQp = ... fA.h/…/A.h/pC/…/kC and dtp = … s
<I> every dt = … s
you can record either an instantaneous current value I or an averaged current value <I>. The
recording conditions during the potential step depend on the chosen current variable. For the
instantaneous current the recording values can be entered simultaneously. Then it is the first
condition reached that determines the recording. A zero value disables the recording for each
criterion. For the averaged current the user defines the time for the average calculation. In that
case the data points are recorded in the channel board memory every 200 µs for VMP3 based
instruments and for VMP300 based instruments.
Leave dI alone for Chronoamperometry experiments, and dQ for Chronocoulometry experiments.
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