18650 2S battery charger

thingiverse

Here's a case for a 2S 18650 battery charger that's easy to build and effective. I bought two cheap "micro USB 18650 TP4056 chargers" from eBay and connected their outputs in series, using separate telephone chargers to feed them with 5 volts each. It's essential to use separate chargers, not a single one with dual outputs, for this setup to work properly. The resulting configuration looks like this: (BAT+) (BAT- connected to BAT +) (BAT-). To complete the case, simply insert the two chargers and glue the cover in place. That's it! I've been using this charger with my DIY Mavic Mini batteries, and it does a fantastic job of balancing the cells while charging them perfectly. You can find the design for this charger on Thingiverse at https://www.thingiverse.com/thing:4544954.