Page 1 of 1

ESP32 powered by 2 x 1.5v Lithium Batteries?

Posted: Thu Jan 23, 2020 7:50 am
by ardcp32
To power an esp32 mostly in deep sleep, I am contemplating to power it by using 2 x 1.5v Lithium AA batteries.
Somebody else suggested this, but even though marked 1.5v, the open voltage is above 1.8v for a new one, two of them giving 3.62 - 3.65v when brand new.
Even drawing a 5 - 10 micro amps the voltage remains at that level.
The esp32 has a maximum supply voltage of 3.6v so this solution does not seem healthy until the voltage drops down to 3.6v or below.

Has anybody experience using this kind of power supply?

Only the bare esp32 module on an adapter pcb is going to be used.

An alternative is to use a CR2 or CR123 as a 3v power supply for the esp32, might need a 1.5F/5.5v supercap to keep the voltage while transmitting.

Re: ESP32 powered by 2 x 1.5v Lithium Batteries?

Posted: Fri Jan 24, 2020 4:06 pm
by username
Personally I would not play that dangerous game running the voltage to its max rating.
Why not just get a couple super caps and put 2 in series. This is what we did and worked just fine for our application.

https://www.mouser.com/ProductDetail/CD ... FlLUCGE%3D

Re: ESP32 powered by 2 x 1.5v Lithium Batteries?

Posted: Fri Jan 24, 2020 7:24 pm
by ardcp32
Thank for confirming my doubts about not using max voltage rating or above.
I find another solution.

Re: ESP32 powered by 2 x 1.5v Lithium Batteries?

Posted: Sat Jan 25, 2020 1:04 am
by pipi61
Try the schottky diode between the battery and esp