user33202: I'm running a project with a nodeMCU DevKit and my project runs smooth if I run it connected through the usb wire to the computer. 
I need to run my project using battery and I tried with a ICR14500 battery (3.7V and 700mAh). I connected the battery to the Vin pin but the NodeMCU doesn't send the data to the cloud.
When I run it with the battery I have detected some random behaviour, some times the led on the ESP8622 is blinking continiously and the total board power consumption is around 130mA!
Any idea what can be happening?

user33226: It seem to be a problem with onboard regulator such as AMS1117. 
ESP are really sensitive to power instability. 
For every of my project i need to put capacitor on alimentation to prevent bugs. 
I think you dont have enougth voltage to work properly with your regulated input.
To correct this issue you should put two battery to get 7.5 volt on the regulated input. 
Another solution is using 3.3v input to pass trought the regulator. 

user38000: If your battery is fully charged it’ll supply abount 4.2V.
The ESP should be able to handle up to 4.7V fine (according to this forum post), except that it’ll draw more current. So there’s no immediate need to go through the regulator.
If you’re battery-powering and want to use deep sleep, also consider using a different regulator with a lower quiescent current (e.g. MCP1702), otherwise the AMS1117 is already drawing at least 4mA.
Blinking and non-operation of the ESP is a sign for errors during boot, e.g. causing boot loops, typically caused by unstable power-supply, e.g. insufficient voltage or that the power supply cannot fulfill the peak current requirements (abount 200mA for the ESP).
My suggestion to be failsafe: just connect two batteries is series (7.4V nominal) and go through a 3.3V regulator.

33202: <p>I'm running a project with a nodeMCU DevKit and my project runs smooth if I run it connected through the usb wire to the computer. </p>

<p>I need to run my project using battery and I tried with a ICR14500 battery (3.7V and 700mAh). I connected the battery to the Vin pin but the NodeMCU doesn't send the data to the cloud.</p>

<p>When I run it with the battery I have detected some random behaviour, some times the led on the ESP8622 is blinking continiously and the total board power consumption is around 130mA!</p>

<p>Any idea what can be happening?</p>
 33226: <p>It seem to be a problem with onboard regulator such as AMS1117. 
ESP are really sensitive to power instability. 
For every of my project i need to put capacitor on alimentation to prevent bugs. 
I think you dont have enougth voltage to work properly with your regulated input.
To correct this issue you should put two battery to get 7.5 volt on the regulated input. 
Another solution is using 3.3v input to pass trought the regulator. </p>
 38000: <p>If your battery is fully charged it’ll supply abount 4.2V.
The ESP should be able to handle up to 4.7V fine (according to <a href="https://forum.makehackvoid.com/t/esp8266-operating-voltage-range-and-sleep-current/286" rel="nofollow noreferrer">this forum post</a>), except that it’ll draw more current. So there’s no immediate need to go through the regulator.</p>

<p>If you’re battery-powering and want to use deep sleep, also consider using a different regulator with a lower quiescent current (e.g. MCP1702), otherwise the AMS1117 is already drawing at least 4mA.</p>

<p>Blinking and non-operation of the ESP is a sign for errors during boot, e.g. causing boot loops, typically caused by unstable power-supply, e.g. insufficient voltage or that the power supply cannot fulfill the peak current requirements (abount 200mA for the ESP).</p>

<p>My suggestion to be failsafe: just connect two batteries is series (7.4V nominal) and go through a 3.3V regulator.</p>
