Arduino Nano project with rechargeable battery by USB


Has anyone done an Arduino project with a rechargeable battery?

I'm hoping to make my project rechargeable but also show the charge progress on a string of NeoPixels. (8 of them)

Is a LIPO the best option? I hear that that are a fire risk if discharged too much?

I also want to charge through a micro USB port.

What are my options?


You should use a LiPo charging module. You can hook it up to run your project, and recharge simultaneously when connected to USB, or other 5 volt source. The neopixel trick won’t work very well, because LiPos, run from 4.3 to 3.7 volts until just before they die, so you won’t get a steadily declining signal.


So whats the recommended best type of battery to use for interrogating the charge level? I really want to display the available charge on an array of 8 Neopixels.


The best battery charge level meters, monitor the time and current being drawn, because voltage is a poor indicator for most modern batteries. A goal of battery design is that they hold the working voltage over the majority of their lifetime, then drop rapidly just prior to complete discharge. Lipos don't like to go below 3 volts, but they will hold at 3.7 to 3.6 for 90 percent of their time. Non-rechargable alkalines and zinc/carbon batteries have a more slopey discharge curve, and a voltage meter type charge meter works on them.