Adafruit MAX17048 LiPoly / LiIon Fuel Gauge and Battery Monitor - STEMMA JST PH & QT / Qwiic | The Pi Hut
Overview | Adafruit LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor | Adafruit Learning System
UPS Power HAT for Raspberry Pi Zero
Amazon.com: Battery Pack, UPS Power Board, Easy Installation Durable UPS Power Board Dual Color Indicator Charger Portbale for Raspberry Pi Zero : Electronics