2 In 1 DC 5V Micro USB To 3.7V Battery Charger Circuit Lithium Battery Charging Module Charge Discharge Circuit Power Bank Circuit For 18650 AA AAA 3.7V Batteries - Udvabony.com - Electronics,
How to Make Lipo Battery Charger Circuit - Share Project - PCBWay
Auto Cut off 3.7 volt Lithium-ion Battery Charger Circuit - Hackster.io
Designing an Advanced 2S Li-Ion/ Li-Po Battery Charge System using MCP73844 IC