First of all, I would never buy anything that you need to plug in from
fasttech...They sell nothing but fakes and clones. 2 of the three "authentic" Mini Protanks I bought from them cracked within 3 weeks.
That aside. An unregulated battery is simply a normal Li-Ion battery. On a full charge it will output 4.2 volts. As it discharges the voltage continues to drop gradually until it discharges (around 3.5 volts). At 3.5 volts it will drop off quickly.
Since e-cigs use relatively low ohm coils in the atomizer heads, this small drop off (.7 volts) will greatly affect vapor production and flavor.
A regulated battery such as a variable voltage or variable wattage battery uses regulation circuitry within the battery to maintain the voltage or wattage at the desired setting rate during the discharge cycle. This gives you a much more consistent vape throughout the discharge cycle.
With a variable voltage battery you can set your voltage to taste, and then vape and the battery will attempt to maintain that voltage until you need to recharge it. However when you change
tanks or atomizer heads, because the resistance in the coil has changed, you may need to readjust the battery again.
With a variable wattage battery you can set the battery to a desired wattage. The battery will note the resistance of the coil and automatically adjust the voltage to maintain that wattage.
I personally like the iTaste vv 3.0. It is inexpensive, has variable voltage and wattage, has pretty much the same form factor as the EGO battery and has a pretty decent 800 mAh rating. It also allows you to charge via USB so you can leave the battery attached to your atomizer while charging and can vape while it's charging as well.
For more information, you can check out my review of the battery here:
http://www.e-cigarette-forum.com/fo...itaste-vv3-review-rev-1-rev-2-comparison.html
