Quick and simple Oozeq supercap
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: https://www.youtube.com/watch?v=XChuZ2XBqbw
The circuit used is a blocking oscillator, but a regular Joule Thief would work fine.