Slider2732 | Quick and simple Oozeq supercap @Slider2732 | Uploaded July 2016 | Updated October 2024, 26 minutes ago.
Charged at 1.2V 100mA for 5 minutes.

This has been another surprise with the Oozeq cornstarch method of making a storage material.
See Robert Murray-Smith's introduction and tests here: youtube.com/watch?v=XChuZ2XBqbw

The circuit used is a blocking oscillator, but a regular Joule Thief would work fine.