10pcs 1a Mini Li Lithium Battery Charger Module Board For Arduino Uno Mega Due Breadboard Pcb 18650 Solar Panel Mobile Power - Integrated Circuits - AliExpress
Li-ion 3.7V battery + TP4056 charger + SX1308 DC step up regulator - low voltag - General Electronics - Arduino Forum
TP4056 1A Li-Ion Battery Charger Module with MicroUSB Port Arduino | Arduino, DIY \ Power Supplies & Chargers