Will it explode?

[Crenshaw]

With all this talk of exploding batteries...i began to worry.

Heres something i just put together cos i thought it would be fun

basically, Q2 on star, a circuit pushing 700mah from 3 AAA batteries.No heat sinking apart from the star.All hot glued together

Its not really about the headlamp, but having a modifed light near my forehead did make me think...what if it exploded? would it? could it?

Which makes me very uncomfortable..

so my question is, under what conditions might, if at all, a light explode, NOT due to the battery..

edit: i tore out everything, and thermal epoxied the star to a largeish brass pump cap of sorts. then hot glued everything back again..shoudl be enough heatsinking for a bit of use now.

Crenshaw

 

[yellow]

wont give good results for some time because of extremely lacking heatsinking; even with that AAA batts, that give it a runtime of under one hour (when everything is the absolutely best value)

but dont fear exploding batts, that ONLY could concern uneven discharged CR123s in a multicell application and possibly Li-Ion cells
(but the latter ones only when heavily overcharged)


why didnt You use any means of focusing? :thinking:

PS: I would fear burning my face - from the 90 degree hot star that melts itself through the housing

 

[LukeA]

That won't explode. The emitter probably won't last more than 20-30 hours, but it won't explode.

 

[WadeF]

I think the question should be "Will it melt?"

 

[AndyTiedye]

If it's 700 ma from fresh-off-the-charger NiMH, it will be quite a bit lower once their voltage drops a bit (I don't see any regulation in there).

If you drive an LED too hard, it will just stop producing light.

 

[Illum]

your thinking of 5mm LEDs going if you drive it on AC
CREE/luxeons don't act the same, it'll cease to light one day...but you couldn't get it it even if you go as far as starting a thermite reaction beside it

 

[Marduke]

I think the question should be "Will it melt?"

Sounds like a great new sister series to "will it crush" and "will it blend" :thumbsup:

 

[Crenshaw]

Good to know that it wont explode then.

Lol, there was a series awhile back, will it blend? the guy blended an ipod, nasty!, he was about to do a crowbar too..

Actually there is regulation, its circuit pushing out 700ma...this one in fact..

http://www.dealextreme.com/details.dx/sku.4382

i dont plan to run it for long times, its more of just a proof of concept until i get round to buying artic alumina,or similar...
i am actually overdriving the circuit cos its a 3Vin,but 3 AAAs are 4.5v. As for any kind of focusing, im waiting on parts to arrive, but it makes a good flood/spill light as it is. Its pretty damn bright, might be pushing 100lumens....unfocused of course...

Crenshaw

 

[xevious]

Yeah, you might want to consider putting a heat shield behind the forehead pad.

 

[Monocrom]

I have that exact headlamp.... But only in stock form.

Why would you put something like that on your head? Wade brought up a good point. It might not explode, but do you really want it on your head, if it starts to melt?

 

[Crenshaw]

well, like i said it was more of a proof of concept then anything else. Its not going to be a headlamp i use much, i will probably get the new fenix one when it comes out for that purpose..

Actually this seems to be THE generic china brand headlamp design... i see it almost everywhere in various lamp formats..

Crenshaw

 

[LukeA]

I have that exact headlamp.... But only in stock form.

Why would you put something like that on your head? Wade brought up a good point. It might not explode, but do you really want it on your head, if it starts to melt?

It's going to be too hot to keep on your head well before it begins to melt.