Flashlight battery charger / power supply

I am looking at the https://www.sparkfun.com/products/15217 “Lipo Charger Plus”. I need to educate myself a bit more but thought I’d start here.

The bag electrolyte batteries aren’t as practical for my design. I’d much prefer to use the cylinder flashlight style batteries we see all over the place now, (e.g. https://www.18650batterystore.com/colle … -25r-18650).

I’m not sure if these can be charged by that charger? I’ll have a bank of batteries to power a IoT device in the field. I’d like to have the option of be able to charge the batteries while the microcontroller, ESP32, is running.

First I just need to know how to charge the flashlight batteries though.

You could, using something like this https://www.sparkfun.com/products/12899 connected to the leads…but it’d probably be easier to use something like https://www.sparkfun.com/products/14457

I like the little holders and soldering them together for my prototype. I really need everything to fit in an enclosure though with one connection to charge and another to power the device.

Not sure if I can modify the charger system to do that? Maybe if I take the case off.

Do you / does anybody know if the little lipo charger plus can handle those flashlight batteries? I really have no experience with building anything for them.

I’ve only built a system for aircraft batteries haha I don’t really know specs for charging those flashlight batteries. Anybody know?

Should be fine - the main 2 things are to never overcharge them (4.2v max), do not discharge a LiPo below ~3.2v to ensure longer battery life, and do not charge them faster than their rated discharge amperage (can cause them to overheat…set the charge rate to 50% of the max discharge, which is determined/indicated by the battery’s specs)

Awesome thanks!