Im building a flashlight and i want to test if a fan in it would be a good idea but the flashlight is really small so i would need a motor thats smaller than 1 cm preferably. I found really good ones at maxon group but unless you order them in bulk(1000+ units) they cost like 400€. So do yall know anywhere i could find them? Thanks in advance! (Edit: Im a complete baffoon and forgot to specify that preferably i would need a water resistant fan. I assumed this because bldc motors without drivers are wter resistant)
In seconds? Wow. I think you’re right, you might need more than a small fan!
It might be worth exploring heat pipes or peltier effect coolers. The latter makes the problem worse (they are inefficient and generate a lot of heat) but your LED can be locally cooler if you can e.g. move all that extra heat into a big heatsink (also condensation can be problematic).
One cheap source of heat pipes for testing could be old graphics cards – they often outperform simple copper heat sinks. Use thermal epoxy to stick your LED to it and see if the performance is acceptable. On the exotic end of things, you could also water/oil cool it, or (carefully) make your own thermal grease from industrial diamond powder for a small boost in thermal conductivity.
Also even at 95% efficiency, it sounds like your boost converter has some heat to dump too!
Yeah the problem is the light makes so much heat(the boost as well) that i cant dump it into the air with high enough efficiency. The bodys going to be aluminium and the pcb copper.
Hm, that reminds me! If you’re designing your own PCB, some manufacturers will make the PCB out of aluminum for you instead of FR4. This is commonly used for high-intensity LED lights to help keep them cool.
Here’s some random info about them so you can see what I mean:
https://www.pcbgogo.com/Article/An_Introduction_to_Aluminum_PCBs_by_PCBGOGO.html
An alternative would be copper-clad polyimide adhered to the body. That also has better thermal properties than FR4.
I was already planning to use a copper core pcb. This is pretty common among insanely powerfull lights. The flashlight community has some great examples. But most of these lights use resistor based voltage regulators which waste a lot of energy in the form of heat so im trying to improve on the traditional design.
That sounds even better!