Potential sweep vs current sweep for a Polarization Curve

[JoJoQuinoa]

Hello,

I'm trying to obtain a polarization curve for a fuel cell (two electrodes in HCl). From what I've seen in literatures, current is applied and the voltage is measured. Is it still the same to change the voltage and measure the current instead? For some reason our equipment only have the voltage sweep option.

Thanks in advance!

 

[Borek]

No, these would be different methods, requiring different hardware.

I admit that's the first time I hear about the "force current, measure voltage" approach. All electrochemical methods I have ever used were variants of voltammetry (vary potential, measure current). From what you wrote voltammetric methods are what your equipment is capable of.

 

[JoJoQuinoa]

@Borek,

Thank you for your response. That's what I've been doing as well, varying the potential and measuring the current. However, from what I've seen in literatures, voltage is reported as a function of current density. Also, this site here stated it as well.
https://www.fuelcellstore.com/blog-section/polarization-curves

 

[Borek]

Are you sure it is "current applied" and not "current drawn"?

Voltage drop under load is an important characteristics of any (chemical) battery.