The JoyeTech eGo Twist Battery is the go to ecig for many vapers. This ecig features variable voltage which allows you to turn the power up, to get a bit more vapor, or down, to save battery life. Designed to run tanks that require a little bit more power to get a much better flavor and vapor production.
These batteries are able to last about 5-10 hours due to the size of the battery, and what voltage level you have it set to. To change the voltage, just twist the bottom of the battery to a selected voltage.