If two aluminium electrodes, in deionised water, were biased to 5V relative to one another, would we just observe electrolysis of the water? Let us assume that the water is perfectly pure, just containing H2O, OH- and H3O+. Or might the passivation thicken at the anode and be reduced at the cathode?
Also, how might the temperature influence these reactions? This is part of an accelerated aging setup, so the experiment is being performed at 67 °C, but we really want to understand performance at 37 °C (for medical implants).