The amount of time a battery will last between charges depends on it's capacity (mAh), as well as factors such as how often it's used, what type of clearomizer you have and what resistance (ohms) your coils are running at. Below is an approximation of how long you can expect your battery to last on average before it will need recharging.
● Small batteries (eg ones which resemble a traditional cigarette): 2-3 hours with constant use
● 650mAh = 6-8 hours of use (approx.)
● 800mAh = 9-11 hours of use (approx.)
● 1000mAh = 12-14 hours of use (approx.)
● 1300mAh = 15-16 hours of use (approx.)