Most people say how many hours and wattage they are using per charge... although I am not a big fan of that method since one could vape once every minute or once per hour. And the difference in hours per charge would be huge. What I like to use instead is how much juice you vape through per charge. And what I really like about it is it doesn't matter if I am vaping at 100 watts or even 10 watts (MTL), the amount of juice per charge still ends up the same. So about 14Wh is about half of what a Reuleaux DNA200 or a Triade has using three Samsung 25R. And they can vape through about 22ml of juice per charge. So if you are vaping through about 11ml of juice per charge (4 hours for you), that would be totally expected. Now contrast this with say a Reuleaux RX200 using those same three 18650 cells, only vapes through 13ml per charge.