Sounds to me like it's the opposite of how an LED works. Instead of creating a small gap that discharges a photon, the material creates a small gap that collects an ion. The ion is then run downstream to the thing that is being powered, making the gap available for another ion.
In other words, it kinda works the same as clouds do to create lightening, the material just facilitates this in a way that can be reliably consumed and at a much, much lower energy scale.