Can protons leave the proton-exchange membrane of a working fuel cell?

[mconnelldouglas]

Can protons leave the proton-exchange membrane of a working fuel cell instead of reaching its cathode because of a strong external electric field?

 

[Astronuc]

What is the nature of the question?

Does such a question relate to the following?

When a proton exchange membrane (PEM) fuel cell runs short of hydrogen, it suffers from a reverse potential fault that, when driven by neighboring cells, can lead to anode catalyst degradation and holes in the membrane due to local heat generation. As a result, hydrogen leaks through the electrically-shorted membrane-electrode assembly (MEA) without being reacted, and a reduction in fuel cell voltage is noticed.

Ref: Ghassan Mousa et al., "Detecting proton exchange membrane fuel cell hydrogen leak using electrochemical impedance spectroscopy method," Journal of Power Sources, Volume 246, 15 January 2014, Pages 110-116
https://www.sciencedirect.com/science/article/abs/pii/S0378775313011981

Or is this about imposing an external electrical field arbitrarily either opposed to the proton current or transverse to the proton current between anode and cathode? The would defeat the intended function of the fuel cell.

Where would the protons go? If unreacted, wouldn't the hydrogen just flow out as excess? Ostensibly, the excess is recycled, but any excess means the system is less efficient.

Background: https://en.wikipedia.org/wiki/Proton-exchange_membrane_fuel_cell