Published on 22 Mar 2014 | over 2 years ago
Salt water battery + Joule thief circuit.
Materials : Copper plate, Aluminum Foil, Kitchen Towel, Warm Salt water, Joule thief circuit
Bigger copper plate & Aluminum Foil is more powerful.
This battery lamp turned on one hour.. but if you replace salt water, it will be lasting until the foil almost erode.