What is the exact battery you received? You said AW but which one? What is the mAh? - should be printed on the side. If it IS 750, you may not have had a full charge even if they did go green when you put them on the charger. If they are 500 mAh, obviously the life will not be 6-8 hours. Also, keep in mind, with your brand spankin new (first HV?) mod, you may have been vaping a bit more than your usual vaping pattern. I know when I got my first HV, I could not put the friggin thing down!
HV veterans, please indulge me while I attempt to share some info with those who may be new to HV. If this IS your first HV, you might consider trying different 3.3 oHm attys on a 5V device. I have no idea which atty Jay sent you but most regular 510s are 2.5 oHm. 901s, and 801s are both native 3.3 oHm and you can get 3.3 oHm 510 attys too. If this is your first experience with 5V, you may find 3.3 oHm brings out more flavor in your juices. And, you will get a bit more batt life with a 3.3oHm atty over a 2.5 as well (just like using LR - 1.7 or 1.8 oHms - atty on 3.7 device shortens batt life - 2.5 oHms will be less batt life than 3.3 oHms).
For anyone else getting their first HV mod, vaping sweet spot is often, to many anyway, more about the watts than the volts. Watts = HEAT. Watts are a combination of the volts and the ohms. While LR attys can "simulate" HV vaping, the vaping experience is "simulated" and NOT the same at all.
The formula is VxV/oHms=watts. So if we use a 2.5 ohm 510 atty on a 5V GLV: 5Vx5V/2.5oHms=10 watts. This is pretty hot and VG burns at lower temps than PG. So, you can burn out flavor at 10+ watts - especially if you use VG in your juices. The more VG the more likely you will suffer flavor loss at 10+ watts. If you use a 3.3 ohm atty: 5Vx5V/3.3ohms=7.57 watts. This is right in the range I find brings out the best vapor and the most flavor from (all) juices. And, equal ohms do not mean the same vaping experience. Get some adapters for 901 and 801 and try each because all three are very different vaping experiences.
If you are vaping at full 6V, you might consider trying a 4.5 oHm atty: 6Vx6V/4.5=8 watts. I find the sweet spot in the 7.5 - 8 (ish) range with 8 being optimal but 7.5 true still waaaay better than LRs 'simulating". I say "ish" because many mods are not restricted like the 5V GLV version.
When you are using removable (not eGo/Tormano/mini(s) as those may be restricted down to 3.2{ish}) 3.7s can come off a charger at 4.2 volts. For those using unrestricted devices stacking 3 Volts batts, I suggest you consider using a charger that has a manual switch to force the charge to limit down to 3 volts otherwise your 3 volt batts may over-charge to the 3.7-4.2 range. This is not an issue for those of us getting the power restricted 5V version but if you are getting the unrestricted 6V version, you could easily end up vaping in the 7.2+ Volt range without knowing it.
There are many inexpensive multimeters on the market, I have one and constantly monitor my batts actual voltage charges so that I KNOW the volts pushing thru unrestricted devices. These are also great for testing the oHms of your attys which can help you keep them organized and separated.
So, like I said, LRs may "simulate" the watts but yield a very different vape. 3.7Vx3.7V/1.7oHms=8.05 watts. But vape 3.7 with LR atty and compare next to 5V mods with a 3.3 oHm attys or 6V mods with 4.5 oHm attys and I am guessing you will see/feel/taste the difference for yourself very quickly.
To those who already know all of this, thanks for indulging my efforts to share this info.