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Can I fit a 10W heatsink in a zippo? Answered

I want to put a cree XM-L LED in an old zippo, and I want to know if anyone knows how to fit a big heatsink in the top part of a zippo lighter, not in the base, and preferably able to buy everything from a hardware store, not ordered online.  Also, does anyone know how to anodize aluminum for added heat dissipation?


Anodizing doesn't increase heat dissipation. You Anodize aluminum to prevent corrosion and in most cases change the color of the aluminum with a die.

I take it the base of the lighter will have the battery and power switch. Well if the case of the lighter isn't a sufficient heatsink then you will need to add some in the lid with the light but it won't do any good unless you can get air to circulate through the heatsink. In which case you would need to vent the lighter casing so the heat has somewhere to go.

Ah, I see for the anodizing, but will making the top of the lighter into a set of fins, then extending one to the LED below the top. Airflow will be provided by just moving the flashlight around. And as for rickharris, yes, I do want 10W, for the sole purpose of being super super bright. Yes, the battery and switch will be in the case.

Fins out the top will be good but you may not find a heatsink that can handle 10W ant will fit on the top of a zippo. The Fins may have to stand an inch or 2 of the top.

i was referring to out the bottom of the top. Basically, the top will be attached to aluminum that goes into the body when closed, but sticks out when open.

I've got a few flashlights...
as leds go...

1 watt is pretty bright
3 watt is really bright
10 watt is unimaginably bright, and my 10w takes 2 large 18560 lithium batteries (like long C batteries). After running for more than 30 seconds in a proper flashlight housing (thermal greased joints) the outside of the flashlight gets up to 40 degrees C (uncomfortable to touch). After 10 minutes its above 55C. My flashlight is 30cm long and about 8cm wide at the head with heatsink fins protruding for about 8 of those cm behind the head.

...so what you're asking is possible if you only intend to 'flash' the light for about a second every minute - or it will burst into flames.

Okay... the battery isn't an issue. My question is whether or not sheet aluminum fins in the top of a zippo will be enough to keep a 10W LED below 100C for 2 minutes. Also, the aluminum, steel, and air will have a decent thermal mass, so it will be able to go more than a second. Heck, if it strobes at 1hz, it probably wouldn't even get too hot with just a single extended fin.

I'm curious what batteries you think you're going to use for a 10W light.

Even at 100% efficiency, it's going to draw at least three amps from whatever battery you find to fit in the case (you'll only be able to fit up to about 3V worth of cells). If the efficiency is lower, then it'll draw even more current to get 10W of output. You'll need to carry around a lot of batteries with you!

An LR44, for example, delivers 150 mA-h at 1.5V. Putting two in series gets you a total of 300 mA-h at 3V. That means you're going to be changing batteries every six minutes. You can get that up to about every twenty-five minutes by using the PR44 (zinc-air) version.

If you have other, higher capacity, batteries in mind, it would be great to know what they are.

I'm using a 3.6V rechargable li-ion battery from a toy helicopter. It can sink about 4A, but at a 3A output, it lasts jsut 8 minutes. I'm not looking for battery life, but insane output from something that size. Also, I want to make a heatsink from sheet aluminum, so that it can be customized to fit in the zippo.

Okay, so your battery has about 200 mA-h, consistent with the numbers I found for LR44.

Good luck with the heatsink. A Zippo lid isn't very large. If you really need something big, you may have to remove the lid and replace it with an external heat sink surrounding the LED.

Oops, I calculated that for a different battery. My battery will only last maybe 2, as it is 50mAh. Also, I probably won't run contiouous duty cycle, and I'm aiming to keep the case itself unmodified, so that it still looks like a regular ol' zippo.

1. What are you trying to do

2. 10 W is a lot are you sure

3. On the basis of your question as it is - Maybe.

how to calculate the correct heat sink size.