Ok,
The array mounted on a CPU heatsink. This the the C4500 array. Made in USA. Has real, legitimate spec sheet. Outputs over 5000 lumens at nominal drive (60 watts). Can be pushed to over 1.5 times that. At 60 watts in (26V, 2.3A) it puts out more light than any 100 watt Chinese array. They have released a 9000 lumen/80 watt array (pushable to 15,000+) that is the same size. I have them on order (delivery date has slipped three times now out to June).
Here the array mounted on a cut down heatsink with 50mm fan. 28 degree Ledil reflector. LED controller. 8S1P A123 battery pack.
The LED is mounted on a cut-down AMD CPU heatsink. It fits in a 3 inch diameter tube that matches the reflector diameter. That's a 50 mm 24V fan on the back. The LED controller adjusts the fan speed depending upon the heatsink temperature. If it gets too hot, it will shut off the LED. Fan comes on at 120F, ramps up to full speed at 152F. Shuts off at 110F. At less than 8W or so drive, the fan does not come on.
The controller is a modified LED dimmer from DALEWHEAT.COM I rewrote the firmware (Atmel ATtiny13A) and changed the voltage regulator so that it draws less than 20 microamps when the LED is off. It is analog dimmable with a pot from 0 to full power in 255 steps. You can also use a pushbutton to step between light levels. Added a second PWM channel to control the fan. There is no power switch. Just turn the knob down and it goes to sleep. At 20 microamps it will drain the pack in about 10 years.
The 70mm Ledil reflector makes a VERY smooth beam with no hotspot. 28 degree beam width at half intensity. I have the reflector mounted so that it can be removed for a 110 degree beam. They also have a medium width reflector.
The battery pack is 8 A123 Systems 26650 2300 mAh LiFePO4 cells in series. It will run the light for an hour at full intensity. About 2 weeks at minimum. Those cells are very deceiving. They can put out 200 amps! One of those 4 cell sub-packs will start a car 20 times in -20 degree weather! Does your flashlight have jumper cables? LiFePO4 chemistry is intrinsically safe. Won't go into thermal runaway or burst into flames, etc.
The LED controller is essentially direct drive. The LiFePO4 chemistry has a very flat discharge curve. 90% of the discharge is between 3.3V and 3.2V. No need for a regulator. The LED controller code does monitor the pack voltage. Too high or too low and it shuts down. A little high and it backs off the PWM to protect the LED and produce what appears to be a regulated output.
Beamshot down 100+ foot driveway (pitch black otherwise). Hard to get a good exposure since the foreground overdrives the camera. This thing will light up a 70+ foot wide tall two story house like it's daylight. Without the reflector it is a 110 degree flood. With the reflector it is 28 degree.
Is it a budget light? Yep, for a portable sun. LED is now $45. Reflector 5 bucks. Heatsink/fan 5 bucks. LED controller 20 bucks (with mod parts). Batteries can be had for around 50 bucks. Free if you can find a "dead" DeWalt 28V pack with a bad cell or two. Package it to suit your tastes.