Battery-Powered ESP8266 Sensor? Never Been Simpler | Hackaday
I'm trying to power a LoRa ESP32 board (SX1276) for a letterbox sensor. The board is in deep sleep until triggered by a pin change (door sensor), sends LoRa message, then returns
Low price wholesale / In Stocks】3V/5V 18650 Battery Shield V8 Mobile Power Bank for Arduino ESP32 ESP8266 Wifi | Shopee Thailand