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By bojankoce
#70849 Hello guys,

I need to use ESP-12S version in my future project. Datasheet says the power supply of ESP-12S is in range of 3.0V to 3.6V.

ESP-12S should be supplied with battery together with the rest of electronics. Can you guys recommend me some battery from your experience?

I intend to use ER14505M model. However, its nominal voltage is 3.6V which is the upper limit of ESP8266. Am I safe to power ESP-12S directly from that battery or it is better to use some kind of LDO 3.3V regulator?

Thanks in advance for your time and effort.

Sincerely,
Bojan.
User avatar
By rudy
#70850 That battery has a very flat voltage. Based on the spec sheet you should be able to run the ESP8266 directly from the battery. No need for a regulator.

Then comes the question of capacity. How long you need it to work.
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By bojankoce
#70876 Hey rudy,

Thanks for your message. Capacity of ER14505M battery is about 2.2Ah. I'm thinking to apply power gating technique and to cut off the power from esp8266 when I don't need it and put the micro-controller into deep sleep mode (2uA of current consumption). This way, ER14505M could last for a few years without a problem.

Thanks once again,
Bojan.
User avatar
By btidey
#70878 That battery is very good match for direct powering as mentioned and has good power density.

A downside would be if you were using deep sleep for much of the time.

The deep sleep current is quite dependent on the supply voltage

https://forum.makehackvoid.com/t/esp826 ... ent/286/41

So operating at 3.6V uses 4 times more deep sleep current than a 3.3V powered system.

One can also get very low power LDO regulators (e.g. XC6203) which would give 3.3V from LiPo batteries. I use that method as I wanted to be able to recharge.