Battery Lithium Ion Polymer 3.7v 1200mAh 2.1mm plug You could also use this

You could also use this on routers

4g Category optical light imaging photon sensors Wiring & usage notes

This module is the integration of 2 sensors

Need a simple wireless connection when Wi-Fi and Bluetooth aren’t available

1/8/7 as a display only Official Waveshare resources

Battery Lithium Ion Polymer 3.7v 1200mAh 2.1mm plug You could also use this3. 7V Lithium Ion Polymer Battery 1200mAh The Lithium Ion Polymer Battery 3. 7V 1200mAh is a rechargeable lithium cell with a JST connector, designed for portable electronics, wearables, IoT devices, and maker projects. Pair it with a LiPo charger like the TP4056 or Adafruit Micro Lipo. Safety: Lithium batteries can be dangerous if punctured, short circuited, or overcharged. Always use a proper LiPo charger with protection circuitry. 3. 7V battery