Powering ESP32 from 18650 (and charging them)

[StevenCellist]

Hi guys,

I am looking to power the ESP32 from an 18650 battery.
Since these batteries have a varying output voltage, I assume I need some voltage regulator, but most I can find in my favorite store that output 3.3V require an input voltage of >5V. Or the output current would be too low (around 200 mA) with no headroom for peripherals.
I found one LDO voltage regulator, the LM3940, with a rated output current of 1A. Will that work?

Also, on the same topic: what is the best way to charge 6× 18650 battery with 4.2V 1A charging specs each? Any suggestions?

[mldevw]

Hi, for my esp8266 I used the same with a diode for voltage drop inbetween so I am only slightly out of spec.
This saves more power than a regulator and furthermore is dirt cheap. The devices are running since 4 years without an issue.
Of course this may or may not work on large scale, I only have experience with a small series