I recently finished the prototype for a battery powered ESP8266 based temperature and humidity sensor with eInk display. Currently working on a custom PCB. : r/arduino
Improving power consumption on my DIY temp & humidity sensor - Project Guidance - Arduino Forum
Shelly H&T is a Battery Powered ESP8266 WiFi Temperature & Humidity Sensor - CNX Software
Battery Powered ESP8266 WiFi Temperature and Humidity Logger
Battery Powered ESP8266 IoT - Temperature Sensor - Home Circuits
Battery powered IoT temperature logger testing
Battery Powered Arduino DS18B20 Temperature Sensor - PiHome
Battery Powered ESP8266 IoT - Temperature Sensor - Home Circuits
ESP8266 WiFi DS18B20 Temperature Sensor (ESP8266 Arduino IDE Without Arduino) | Arduino, Arduino wifi, Arduino projects
ESP8266 ESP 32 18650 Battery Shield WIFI Bluetooth DHT11 CP2104 Temperature Humidity Soil Moisture Sensor Module for Arduino|Integrated Circuits| - AliExpress
Battery Powered ESP8266 IoT - Door Sensor - Home Circuits
Battery Powered Arduino DS18B20 Temperature Sensor - PiHome
Low power ESP-12F MQTT temperature/humidity sensor - Everything ESP8266
I made an ESP-01 temperature sensor that sends data to Home Assistant via MQTT. Based on a prototype using a smaller battery I'm hoping it will last 4+ months. : r/esp8266
Design your own ESP Board for Battery Powered IoT Applications
Battery Powered ESP8266 IoT - Temperature Sensor - Home Circuits
Battery Powered ESP-01 Temperature Sensor - Technology Spy