But which modern mobile devices use AA batteries anyway? LiPo batteries seem to be the obvious choice for commercial products, so why not use them in your DIY projects? Well, there are a few problems that you have to master in order to do so:
- LiPo batteries usually have a nominal voltage of 3.7V but an actual cell can have a voltage from around 3.2V (empty) up to 4.2V (fully charged). And 4.2V is far too much for the VCC of a ESP8266.
- LiPo’s don’t like over- or undercharging very much. They can overheat and catch fire and who likes to have a fire hazard in the home?
- LiPo cells come in various forms and are equipped with different features. Which one is the right for your project?
A ridiculous amount of coffee was consumed in the process of building this project. Add some fuel if you'd like to keep me going!