We really advocate working with an external battery charger for 18650 battery mods, as it helps with balanced charging and prolongs the life of the battery and mod, for example from worn out microUSB port.GuidesGuides 2Guides 3Guides 4Guides 5Guides 6Guides 7Guides 8Guides 9Guides 10Guides 11Guides 12Guides 13Guides 14Guides 15Guides 16Guides 17Gui