Simple PowerBank

thingiverse

WARNING! Handling batteries and connecting them incorrectly can be extremely hazardous. Batteries may catch fire or even explode, causing devastating damage. Get connected by someone who knows what they're doing. A PowerBank is surprisingly easy to build. - Gather 18650 batteries from old laptops, power screwdrivers, and other devices. - Place the batteries in the two 18650 battery holders. - Connect them securely. - Attach a small USB charging module, like this one: https://www.banggood.com/Dual-USB-5V-1A-2_1A-Mobile-Power-Bank-18650-Battery-Charger-PCB-Module-Board-p-1031593.html?rmmds=myorder&cur_warehouse=CN. - Insert a small M3 screw (plastic) into the tubular hole from inside the case, leaving it two mm longer and cutting off the excess. - Put everything in the case and stick the elements together with hot glue. - And... That's all there is to it!