Self-charging supercapacitor power cell (SCSPC)

[Bertoa]

Take a supercap, make a shortcut to clear and measure a day later the voltage. Depending on the type of supercap, you measure a voltage between 100 mV and 300 mV. With 2 supercaps in series, this can rise to more than 1 volt after a few days. A self-charging supercapacitor power cell (SCSPC) attains tremendous research interest due to their ability to harvest-, convert-, and store- energy in a solitary integrated energy device. The use of liquid electrolytes in SCSPC limits the mechanical to electrical energy conversion efficiency, therefore, the development of alternative electrolyte system has priority.
Research developed a piezo-electrolyte film comprising of solid proton conducting electrolyte (phosphotungstic acid (PTA)) embedded in the piezoelectric PVDF matrix and use these free-standing films as separator instead of electrolyte for use in SCSPC devices.
So, free energy is at hand in one device, the supercap. I made a test setup with 2 double layer supercaps of 22F in series and can confirm that this works. After 2 days I measured 1 volt, enough to power every now and then at nano/micro scale a loT device.

[Paul-R]

Why not an ordinary cap?
Is this any different to static charges building up here and there?

[skywatcher]

It works, but only a few times. Every time the end voltage gets lower. And it's not 'free' energy. Batteries show the same effect. After you 'discharge' it, voltage will come up again.