ok this is battery extending on almost the cheapest possible ...
4 batteries
1 battery holder
severed usb wire
optional? - usb charging cradle
since the output of 4 rechargeable batteries is close to 5 volts this works rather well. except one thing, you have to remove the batteries from the holder and charge them in a real charger ...
options:
- search for battery extender on ebay, they are a bit nicer than my electronics project battery holder ...
- you can omit the cradle if you can find another way of securing the wires to the right spot, it is empty! ... there is only a led in its circuit ...
how to wire this ghetto contraction for dummies
1 charge batteries
2 put in holder
3 connect usb end of severed wire to charger without ux!
4 try different combinations of wire until the led lights up
5 solder the wires in place
6 secure wire with some strips
7 go brag to some eb40 owner that you made a more powerfull battery extender for $20-$30
warnings:
- havent tried it with regular batteries, they would be 6v together, I guess it would be well within the ux voltage regulation limits, but somehow I don't want to be the first to try