We shot a quick video of the DIY Dynamo charging our external battery that we covered in a previous post. It is connected up to a dual multimeter test box that Phillip worked up. Note that the dynamo is sending about 4.5V and about 400mA into the battery (these numbers bounce around a lot). If Phillip could keep up the pace, he would have a full battery about 8-10 hours from now. Solar certainly seems easier!
Here’s the full post on how to build battery charging dynamo.
Maybe this could be driven by a bicycle?