I don’t have your particular mod but mods have some similarities. While you generally can charge a battery in the mod using a microUSB2 cable it is not recommended. The port is very fragile and daily charging will likely wear it out or break it. Also it doesn’t do it very well. It may not fill the battery all the way, it may take a really long time, it may stress the battery underlying, etc.. external chargers are better, faster, safer, and if you have more than one battery you can effectively instantly charge the device by swapping out batteries.