[Royal]

Here is a good way to get an idea how long a battery should last you on one charge.

If you are running an atty at 1.67 amps, a 510 for example, you would need to have 1.67 amp hours of power to run the atomizer for a full hour. So if you are using a 280 mah 510 mega battery for example, with a 1.67 amp atty draw. You can calculate how much run time you can expect to get by dividing the amp hours of the battery, in this case is .280 divided by the amperage draw of the atomizer which we will say is 1.67 amps which comes out to .167, multiply that by 60 for the amp hours in minutes will give you approximately 10.02 minutes of total run time. This comes out to approximately 120 drags at 5 seconds each, or approximately 200 drags at 3 seconds each.
Surmising that 15 drags will equal one analog, this equates to 8 to 13 cigarettes worth of use out of each charge for a battery rated at 280 mah, depending on the length of time of each draw.

Resistance and peak amperage changes during the course of the heating process, as so does the actual peak voltage of the battery so this calculation does not consider these and other factors.

So using these calculations you would be getting close to 3 to 5 analogs worth of vaping time for every 100 mah of battery, depending on the length of each draw.
Supposing you are taking 5 second draws and you smoked 1 and a half packs per day, this would come out to 1000 mah per day of battery usage at 5 second draws, or 600 mah per day if 3 second draws are taken.

This can give you a good idea if you are vaping more than you smoked, or how many batteries or charges you may go through in one day.