Best 18650 Battery Chargers for Vaping (2-Bay & 4-Bay Chargers)
If you don't have an external battery charger, get one! It makes so much of a difference in battery life compared to a usb charging removable batteries in the mod. This cost
Amazon.com: Nitecore i2 Intellicharge Charger for 18650 AAA AA Li-Ion/NiMH Battery : Electronics