Amazon.com: AITRIP 6PCS 2A USB 18650 Lithium Li-ion Battery Charger Module Boost 3.7V to 5V 9V 12V Adjustable DC-DC Step Up Boost Module TP4056 DIY Kit Parts : Electronics
DIY - Single Cell Lithium-ion Battery Charger
5V 1A USB Lithium Li-ion 18650 3.7V Battery Charger Module Board DIY Power Bank | eBay
Adafruit Universal USB / DC / Solar Lithium Ion/Polymer charger [bq24074] : ID 4755 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Open source DIY friendly Li Ion battery charger – Dangerous Prototypes
Lithium Ion Battery Charger
DIY Solar Battery Charger for 18650 Li-Ion Batteries | Solar battery charger, Solar battery, Solar charger
5V 2A USB-C Type-c Fast Charger Module 3.7V 18650 Li-ion Battery DIY Power Bank | eBay
Ultimate DIY Lithium Battery Charger: Improve Performance with Resistances and Converters — Eightify
5V 2A Dual USB 3.7V Lithium Li-ion 18650 Battery Charger Module DIY Power Bank | eBay