In an electric double layer capacitor(EDLC) (or any situation with a Helmholtz double layer) what prevents the ions from being reduced or oxidized like the ions in an electrochemical cell?
If it is because the potential is not high enough, what energy barrier is preventing the reaction?
In the negative ion case, is it that even though the ion has a net negative charge and as a whole is attracted the the positive electrode the electron feels a stronger attraction the the nucleus than the the electrode?
Is this what determines the maximum voltage of a supercapacitor?
How does all of this relate to the inner and outer layers?
Sorry for so many questions in one post but I think they are all related and I hope that they provide context for my confusion.