ESP32 Forum

I need to run my esp32 on coin cell battery, I have two CR2450 3volt battery connecting in parallal. I establish a wifi connection to send temperature data once a day, after that esp will go to sleep. but the esp is not working with the coin cell. It shows brownout.
Is any extra ckt should i use to run the esp32 and how long the battery will run?

Your issue is that a coin cell has a fairly high internal resistance, meaning that when the ESP32 needs a fair amount of current (e.g. when initializing/using WiFi) the battery output voltage drops by a lot. That's what a 'brownout' is. There's no easy way to fix that other than to use other battery tech (e.g. LiIon cells have a lot lower internal resistance), or to use e.g. a supercap as a buffer for the high current.