You can run a high drain cell to about average 50W and 80W when its full, but the current will be too much for a converter
And its important for you to get at all times the same light output, so a buck/boost converter with a current limitation is needed
I would suggest 2 cells and a buck converter the LEDs running on 1A depending what the heatsink can manage
Those 5A rated buck converters I trust only up to 3.5A some trustworthy sellers do the same
I wouldn’t run a triple 219C on 60 Watts.
They’re rated around 5 Watts each, so a triple would be 15 Watts, and it wouldn’t get too hot and still be efficient.
I get what you’re saying though.
With the low Vf of modern LEDs it seems a bit wasteful to use a linear driver (constant current with 7135 for example) which will simply burn off the excess voltage.
A buck driver on 2x 18650 in series would be nice for a 219C triple.
For 15 Watts you need approximately 5 Amperes driver output.
Should do around 1500 LED Lumen (you will lose some in the optics of course)
This converter can be used for series LEDs and you can adjust the max current
As for all of this type you need 2 series batteries as the start to work at 4V
You can use an external potentiometer to variate the lights nrightness
I did a video about this
Parallel LEDs will limit the max current as the buck converter of this size usually is limited to 5A
It cant be run on a single cell as the electronics need at leat 4V to operate
Fid you ever touch a 18W LED lamp when it ran a while?
The heat has to go somewhere, 3 nichias at 2A will produce 13W heat, thats more important than speculating on 4A per LED
I can build you such a light, because I have the knowledge of electronics and heatsinking them
If sou just add a ring of aluminum and mount 3 LEDs @4A on them the will cook themself in less than a minute, reaching soldering temperature and fall off on best case
Texas_Ace, what type output would you expect?
Lexel, why 2A and 2 cell? It says 4A input and 94% efficiency. So that should be 3.76A output. And it says it works down to 3v, granted, I will need to stay above 50% SOC to keep getting 4A.
4A input at 3.6V = 14.4W
The battery will go down to 3V if empty so its only 12W in worst case
I am a hobby photographer and I can tell you that 3 spotlights on a macro lens will give you not the result you are aiming for
It is better to go with 1.5W 7030 LEDs that are also availiable in 95 CRI mount them as close together overlapping each other and add a suitable diffusor foil
Running 3 nichia LEDs at 1.8A max rated current will work on a single cell of you get the regulation IC supported with a higher boltage like from an 9V battery buts its easier to ass a 2. lithium cell and double the output power
This is a light strip for example.
Would need a custom board and can be run with a boost converter
If you do no macro its easier to get Nichia 219 on DTP copper stars and mount them on a circular heatsink I linked above you cut in 3 pieces
Ideally for professional DLSR lenses you can do 6 Nichia LEDs with those heatsinks cut and arranged in a circle
6 Nichia run at 1.8A with 2 boost converters off 2 18650 batteries will result in 4000 Lumens
Those prices are scary for a camera light.
So the original plan was to use 3 triple boards round the camera lens with 1 led each. Because they are triple boards, the LED can be placed close to the lens and hide shadows. I would use 2 large hole-saws to create an aluminum doughnut to screw them to. But the driver and batteries are going to make it a real bulky setup.
Perhaps I can leave all 3 on one board and just stick it in my 26650 zoomie. I’m not sure my driver can handle it, but it’s getting tempting.
Edit: my battery would only drive 2 LEDs. I might do it anyway to try.
A protected 26650 battery and FET driver with a triple wont work it will trip overcurrent protection even with 2 LEDs
A zoom light will not work great at all because the lens ruins CRI by splitting the lights gradually in its colors nor will it have useful beam pattern
Just a piece of aluminum will get coocking hot in no time, you need proper heatpath to air to stay within a safe temperature of the LEDs
Well I can limit current by not fully charging the battery. The battery protection doesn’t cut power until over 8 amp. Perhaps 2 LEDs will be all the heat I want to deal with too.
A single 219C will try to pull over 10A, you do not want protected cells with 219C’s.
What kind of camera are you talking about here, video or photo?
A lot of the better video cameras will have mounts for microphones that could hold a flashlight quite easily. Or they sell universal camera mounts that mount to the camera tripod that allow you to attach all sorts of things while offering more stable footage as well.
A single 219C will try to pull over 10A, if it has sufficient voltage to accommodate that 10A. But after looking at the graph again, damn, that is a flat curve…. 3.4 is good. 3.8 is too much…