Streamlight 4aa plus nimh=danger?

After searching through old messages here I gather that using non-alkalines in the Streamlight 4aa led flashlight would nullify the warranty in the case of it blowing up, but does using nimh actually pose a greater risk?

I use lithiums exclusively in all my SL 4AA lights, without issues.

Which one?

Of the 4AA Pro Poly models, the only one where I noticed a difference in output was with the incandescent lamp assembly. The output from a fresh set of alkalines was notably better than what I got from freshly charged NiMH or NiCD batteries. Never noticed any difference with NiMH batteries in either the 7LED or Luxeon models of that light, if anything, it's pretty much a consensus that you'll get a little longer run time using the NiMH batteries over the alkalines. Not sure that using NiMH batteries would necessarily nullify your warranty, I don't see anything in Streamlight's warranty that would specifically void your warranty if you used NiMH batteries, however I don't see where they would be liable if your NiMH batteries leaked any more than they would if alkaline batteries leaked. The only Streamlight product that had an explicit warning about using specific brands of batteries are those Streamlight products using the Lithium 123 batteries; there's a bright red sticker on the package with that warning.

ebony said:

After searching through old messages here I gather that using non-alkalines in the Streamlight 4aa led flashlight would nullify the warranty in the case of it blowing up, but does using nimh actually pose a greater risk?

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Brighteyez said:

Which one?

Of the 4AA Pro Poly models, the only one where I noticed a difference in output was with the incandescent lamp assembly. The output from a fresh set of alkalines was notably better than what I got from freshly charged NiMH or NiCD batteries. Never noticed any difference with NiMH batteries in either the 7LED or Luxeon models of that light, if anything, it's pretty much a consensus that you'll get a little longer run time using the NiMH batteries over the alkalines. Not sure that using NiMH batteries would necessarily nullify your warranty, I don't see anything in Streamlight's warranty that would specifically void your warranty if you used NiMH batteries, however I don't see where they would be liable if your NiMH batteries leaked any more than they would if alkaline batteries leaked. The only Streamlight product that had an explicit warning about using specific brands of batteries are those Streamlight products using the Lithium 123 batteries; there's a bright red sticker on the package with that warning.

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I have the 7-led model. My main concern is the use of nimh in the SL4AA. I have plenty of nimh AAs and would prefer to use them, and would use them even if I risked nullifying the warranty so long as there wasn't a safety issue with the nimh AAs--which so far it seems there isn't. Thanks for the reply.

With the 7LED model, if anything, you'll prolong life and lessen the possibility of damage to that light by using NiMH batteries. That lamp assembly tends to be a bit overdriven when it is used with alkalines. But it's a great light for short range flood though; probably one of the better LED lights out there for the price.

ebony said:

I have the 7-led model. My main concern is the use of nimh in the SL4AA. I have plenty of nimh AAs and would prefer to use them, and would use them even if I risked nullifying the warranty so long as there wasn't a safety issue with the nimh AAs--which so far it seems there isn't. Thanks for the reply.

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Brighteyez said:

With the 7LED model, if anything, you'll prolong life and lessen the possibility of damage to that light by using NiMH batteries. That lamp assembly tends to be a bit overdriven when it is used with alkalines. But it's a great light for short range flood though; probably one of the better LED lights out there for the price.

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Not necessarily since NiMhs sag a lot less than Alkalines even though nominal voltage is lower (actually not much since NiMh's come off the charger at around 1.43-47v too). If they designed the SL4AA LED to run on the Alkaline discharge curve, then it's not going to like the NiMh one.

But usually, just a little more volts never hurt anyone. Maybe it'll take a few hours off the LEDs 100,000 hour life. No biggie

When initially introduced, the 4AA Streamlight was apparently designed with a view toward the resulting power of an alkaline after a few minutes use. Lithium and rechargeable produced a flat loss that apparently could overdrive the lights for too long. Some on the forum damaged their lights during that initial period. Streamlight stood behind them, repairing them and adding additional resisters to the circuit. Later Streamlight began putting a warning on the package stipulating alkaline cells only.

I would imagine they've probably ironed out the problem by now. Mine is the older one though, so I'm only using alkaline in mine.

Theory is nice and I can see where a lot of it may end up on a board like this, but in actual practice I have managed to cause some damage to the 7LED head using alkalines, and in his review, it would appear that Doug also arrived at the same conclusions over at flashlightreviews.com.

Please do note that this is specific to the 7LED lamp assembly, not to the incandescent or Luxeon assemblies.

LEDcandle said:

But usually, just a little more volts never hurt anyone.

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Well, use at own risk....
Always follow manufacturer's spec if you don't know what you are doing... Don't listen to me!