The best you will get out of an eGo battery is 0.65A or 1A that is with 650 and 1000mAh respectively. A 1.5 LR draws 2A on an eGo battery.
This is incorrect.
The ratings 650mAh and 1000mAh do not state the maximum current output of the battery. Rather, they state how long the battery will last given a particular current draw. For example, a 650 mAh battery can deliver 650 milliamps (0.65 amps) for one hour. The 1000mAh can deliver 1000 milliamps (1 amp) for one hour. So, if you're using a 3.7 Volt 1000mAh battery, it works out like this:
I = current (amps)
V = voltage (volts)
R = resistance (ohms)
3.7 volts across a 1.5 ohm atomizer:
I = V / R
I = (3.7)/(1.5)
= 2.47 amps = 2 470 mA
This is the current that the atomizer will draw from the battery. To find out how long the battery can deliver this current, you do the following:
time (hours) = mAh/mA
= (1000)/(2 470)
= 0.405 hours
Therefore, with a 1.5 ohm atomizer, a fully charged 1000mAh 3.7 volt battery will last for 0.405 hours (24.3 minutes) of constant use.
Separating this 24.3 minute time frame into 5 second "draws,"
24.3 minutes * (60 seconds)/(1 minute) = 1458 seconds
1458 seconds * (1 draw)/(5 seconds) = 291.6 draws
You can do your own math based on how often you tend to take a draw to determine how long it will last you. My own personal experience is that, with a 650mAh 3.7 volt battery, using a 1.5 ohm atty lasts me about 24 to 36 hours while using the standard 2.2 ohm atty lasts me about 48 to 60 hours.