The easiest way is try something simple without profound theories
is to employ an insulator-spaced stack of 100 stainless steel Fender Washers
(1.5 inch diameter) on a nylon rod using 120 volts rectified with a full-wave bridge placed in
a horizontal water filled and capped 2.0 inch diameter PVC with the
rectified voltage applied to each end washer. That should divide
each "cell" to about 1.5 volts.
Vapor out one end, make-up water in the other.
With or without voltage applied the metal-water interface
Helmholtz Double Layer is a "supercapacitor".
