Can we add heat radiator/dissipation betwee flashlight head and battery?

[hank]

One issue I notice more as I get dragged kicking and screaming toward brighter and hotter flashlights — battery temperature.

I think this can only get worse for a while (until we have cold light emitters that are brighter than fireflies).

So I have wondered in the past about adding more extensive cooling fins — “ray gun” style — to flashlights.

I’m starting to see hardware that could do that —- if threaded adapters could connect it in between flashlight head and battery tube.

Here for example: https://www.fasttech.com/products/2022301

[hank]

This sounds like the direction flashlights are going:

A bit from motorcycle/auto engine history:

A problem with air-cooling: While a vehicle’s power requirement rises roughly as the square of its speed, the velocity of free-stream cooling air varies only directly with speed. Practice was always ahead of theory on this one—if engines ran so hot that they detonated, designers gave the next model more fin area……

The Love of Cooling Fins

Well I’m seeing reports of flashlights getting very hot — which means the batteries inside also are getting quite hot.
We know heat cycling degrades li-ion cells — though I’m not sure we know how fast or how bad. Nothing has “detonated” from heat yet (yeah, I know, in IC engines that refers to knocking, premature detonation)

But I just saw mention of a flashlight getting too hot to hold before its driver’s temperature sensor throttled it down. We’re getting into interesting territory here.

RC modelers are adding cooling fins onto their tiny little internal combustion motors. Some sure look like they might work on flashlights.
https://www.google.com/search?q=cooling+fin+RC+model

Anyone here overlap both activities who’d know more and have hands-on experience?

[JasonJ]

I’m familiar with the heat sink/cooling fins that the RC guys are putting on the electric motors… and I agree, a threaded fit-in adapter with additional cooling capabilities could be helpful in some cases.

[Rufusbduck]

Lol, you guys need to pay more attention. Myself and others have been doing this for quite some time(adding more fins).

[JasonJ]

I never stated that I didn’t know of the existence of additional cooling adapters, just that I agreed they can be helpful.

In fact I’d be shocked if they weren’t being machined already.

[hank]

I’m asking about adding additional metal for heat radiation — as the RC folks I found are doing — if that helps clarify the question.

Rufus, if you’ve been doing that here, I’ve missed it. It’s a big place, I do know about removing metal to increase the surface area — but haven’t seen mention of doing that either.

Pointers welcome to better info, as always.

[Fritz_t_Cat]

Some flashlights have one or more thin places between the battery tube and the head, the SK-68 for example. I have thought of this as a defect and even tried to fix it because I want the LED to be cool, but it may be to keep the battery tube cool, either to keep the handle feeling cool or to keep the battery cool.
The fins on the SK-68 are below the thin spot, so they cool the battery tube better than they cool the LED.

sk68 clone: longitudinal section

Hi, I won a sk68 clone in a Tinydeal thread a few months ago, and their deal was that I had to write a review in return. I ignored that a little because a review is quite an effort in return for such a cheap light, especially because it would be boring: just about everything has been said about the sk68 already. And again, and again, and.... And all possible mods have been done and documented (some by me). And then last week I got a polite PM from Jane to remind me of the promise [image]. So I…

[hank]

What we need is a module that’s seriously designed to emit both light as wanted, and heat out the sides.

Have a spacer, or an airgap with posts, made of stainless steel or some other poor heat conductor to carry the wires and connect to a battery tube.

Flashlights with LEDs ought to be designed for heat dissipation as thoughtfully as they are for light production.

Not that this is news.

Ceramic Heat Dissipation—Less Is More

A simulation process based on Computational Fluid Dynamics supports thermal optimisation and technical product design. So let’s explain the theoretical approach, the proof of concept, and what and how improvement with ceramic heat sinks can be achieved.

LEDs are known to be efficient and are loved for being tiny. But they are only really tiny as long as heat management is not involved.

[Ronin42]

Do you want the LED cool, or the Battery cool, it is a challange ot have both (using our crazy circuit designs)

or like this?