Hey guys, I have a Maksi that uses the custom 5v batteries. Is it normal for the battery life to only be ~30 minutes of heavy vaping? I have 2 chargers and 4 batteries and rotate them. The batteries run out so quickly that it's a constant cycle. If I had less than 4 batteries I'd be dead in the water for a little while. Is this normal? These batteries only have ~3 weeks of use.