One of the great benefits that LED technology has brought to our hands is the possibility of developing relatively complex projects at a reasonable cost. A good example is the super LED flashlight built by Samm Sheperd, which combines a total of eight 100-watt LED chips each, and a liquid cooling system made with parts purchased on eBay. The result is a light with a luminous flux of 72,000 lumens, almost seventy times more powerful than a standard commercial LED flashlight.
According to the price lists on eBay, a 100-watt LED chip from China costs less than two dollars. Depending on the quantity and the project you have in mind, you will most likely need a power supply, although there is always the possibility of using a battery pack, thanks to the flexibility in the operating voltage that these chips present (9-35 volts, in theory).
If the plan is to build a flashlight, batteries are surely on your list, but what will undoubtedly appear at the top is some cooling system for each LED module. Those little devils heat up a lot, so it is critical to dissipate heat properly, unless you want burnt LEDs in a matter of seconds. That said...
What about a liquid-cooled flashlight?
In essence, what Samm Sheperd did was connect eight LED chips of nine thousand lumens each (maximum) to three 12-volt batteries in series. The chips were installed on a cooling block whose liquid flows thanks to a small pump installed inside a bottle, and a fan coupled to a radiator dissipates the heat, while the lenses do their part distributing the light. The liquid circuit is wide enough to keep the lights at an acceptable temperature, although with the battery pack he used, the flashlight only lasts about six minutes on. The number of batteries the user wants to connect depends on how much portability he is willing to sacrifice.
Since there is no standard design, Sheperd relied heavily on epoxy to keep everything in place, and on the use of aluminum, combining strength and low weight. It is definitely a "cannon of light", which leaves most commercial flashlights biting the dust, and we must also remember that "white" is not the only color available in this type of LED light. If it were to go on sale, the flashlight would have a price close to $500, however, buying the parts on our own should be a much more economical project.
