You need to buy hi quality batteries like these, from these webpages:
1) AW RCR chemistry 16340 size 3.7 volts 750 mAH with protection circuitry:
http://www.cpfmarketplace.com/mp/showthread.php?144427-NEW-Hi-current-Protected-R123s
2) AW IMR chemistry 16340 size 3.7 volts 550 mAH with no protection circuitry:
http://www.cpfmarketplace.com/mp/sh...18650-IMR26500-*Part-2*&p=2272984#post2272984
These high quality batteries have low internal resistance to deliver a faster discharge rate, hence more current, for greater brightness.
The RCR chemistry can discharge at up to 1.5 amps, and will deliver your V11R's 500 lumens.
RCR chemistry has a higher capacity, and protection circuitry to prevent overdischarge.
The IMR chemistry can discharge at up to 4 amps!
Used in a Jetbeam RRT-01 or a Niteye equivalent, the Niteye in particular can deliver 650 lumens using IMR chemistry.
However, IMR chemistry lacks the mAH capacity, and cannot have a protection circuit.
So, if using IMR chemistry, once the light steps down or cuts off, we must stop and recharge almost immediately; in this situation further use of the flashlight may permanently damage the IMR chemistry battery.
Furthermore, if an IMR chemistry battery becomes flat, and you store it for 1 month, you may find that 1 month later, it will not recharge.
IMR chemistry battery has no over-discharge protection circuitry, so it requires careful use and maintenance, but it can discharge at up to 4 amps for tons of lumens.
Btw, the low quality battery with high internal resistance, and a slower discharge rate, can be used on flashlights with XP-G emitters, because their maximum current is ususally only 1.5 amps.
Cree XM-L emitters can be driven to 3 amps.
Luminus SST-50 emitters can be driven to 5 amps
While SST-90 can be driven to 9 amps.
Of course, all these emitters can be "over-driven" beyond the manufacturer's max recommended specifications, but the life span will shorten.
A Trustfire charger is satisfactory.
An Ultrafire charger is better.
The best is either a Pila charger, or a Jetbeam or Nitecore i4 Version 2 Intellicharger with 4 bays and multi-battery type ability.
The i4 Intellicharger is versatile, a bargain, and great value for money...