Charge a 18650 battery using the cheap TP4056 circuit boards available on ebay.
There are holes in the cradle to allow a cable or paperclip to go through. This gives more stability and stops the paperclip from moving. There are also grooves to hold them in as well.
Inspired by Kauz's charger for the CR123A battery.
| 18650_battery_charger.stl |
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