e cigaretter batteriesThe battery is a lithium ion 3.6 volt rechargeable. It can last up to 3 months. It has a computer chip and a little silicone flap connected to contacts that activate it.

Depending on the model you buy they come in from 150 mAh to 280 mAh.  The mAh rating determines how long it will last between charges. Since the switch is activated by drawing on the atomiser, there must be airflow, hence the liquid, if overfilled, can get into the  battery and  mess up the function of the switch.

It also has a computer chip inside that shuts it down if you have taken a draw exceeding 5 seconds or if the voltage is low and it needs recharging.

There is a LED at the end that will flash if either of these occur, and lights steadily during a draw. The biggest problem with the battery is the liquid getting into it. It can make it short the switch out or make it sporadic in function. Make sure you keep the connections clean by wiping them with a paper towel.

If the battery is malfunctioning, try blowing into the end of it by mouth or with a can of air. Tap it on the table a few times lightly to dislodge any fluid that might be impeding the contacts. Wipe it clean and try it again.

There are also the manual batteries which contain a small button you press during a draw. These tend to have less problems than the autos but prohibit hands free operation and usually don’t last as long between charges. They are very popular because you can take as long a draw as you like, and are less likely to malfunction.

The chargers have an LED light that is supposed to tell you when it is charged, but they are not reliable. I suggest you charge the battery for at least 3 hours when it is dead, regardless of the light, this way you will get the most out of your battery.