Design your own ESP Board for Battery Powered IoT Applications
Mini ESP8266 Wifi Development Board 18650 Lithium Battery Charging Module for WeMos D1 ESP-Wroom-02 Mother Board Nodemcu PWM I2C
For WeMos D1 ESP8266 Esp Wroom 02 Motherboard Mini WiFi Nodemcu Module – Aideepen
lua - Check the battery status with NodeMCU? - Stack Overflow
Diymore Wemos Mini D1 Esp8266 Wifi Wireless Nodemcu Module Development Board 18650 Battery Case Esp-wroom-02 For Arduino - Integrated Circuits - AliExpress
Can i power this 'nodemcu esp8266 v3' using 7.4v or 8v power source in its microusb. actually i have two li-ion battery(3.7v) so , i am going to connect this battery in