Smart Battery Charger
gfwilliams @ instructables.com has build a smart battery charger that is able to individually charge each battery , automatically discharge them and give you an idea of their capacity. The charger is controlled by an Espruino Pico and results are displayed on a Nokia 5110 LCD display.
If you’re anything like me you’ll end up with a lot of rechargeable batteries, none of which end up being charged properly, and some of which turn out to be completely unusable. It’d be perfect if you had a low-power battery charger that you could leave on all the time, that would charge your batteries individually, automatically discharge them, and give you an idea of their real capacity. That’s what you’ll make in this tutorial!
Smart Battery Charger – [Link]