Optimizing ESP8266/ESPHOME for battery power (and making an ice bath thermometer as well)

It’s been a long while I wanted to check for how long can an esp8266 with esphome last on a battery supply. Yet I didn’t have a reason to get it done. Time to fix that and add yet another battery optimization manual for ESP8266 to the internets.

And what’s the big reason? The story is simple. I decided to try ‘cold water immersion’ practice and make it a habbit.Yep, not the cold showers, but true hardcore ‘CWI’. I started back in summer when it was hot as hell and went all the way through to November. The weather gradually lowered the water temperature for me from ‘ah, cool and nice’ to ‘Awh shit this is cold!11’. Ideally that would become a habit.

However in November I had to pause that for a few weeks. And that meant the only thing: I had to start over again. And since the weather isn’t helping me any more, I’d have to take care and gradually decrease the temperature myself.

The first idea was to just order a dumb water thermometer. But why order when you have all the parts in stock and can just build one? And with cool features!

Hard as a rock, dumb as a brick (c)