18650 light with built in protection circuit?

Mjolnir

Flashlight Enthusiast
Joined
Dec 19, 2008
Messages
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I recently found an old laptop battery with 8 18650 batteries (unprotected) inside it. They all seem to work fine and don't seem overdischarged (most were at about 3.5 volts; 2 were at 3 volts).
Are there any 18650 lights that have built in protection circuitry (mainly for overdischarge protection)?
 
L-mini. Cuts off at 2.7V under load.

Do note that you should be able to cut off the protection circuitry from a protected cell and adapt it to any light. This way the light is protected, and you can use whatever cells you want. Some DIY skills would be needed though.

Check the 3V cells repeatedly; they should all be at the same voltage inside the pack. Since those weren't, they are probably bad.
 
Yeah it seems like those 2 were bad, as they won't charge past about 3.9 volts. Is 2.7 the standard lowest voltage that 18650's should run at to avoid overdischarge, or is it different between batteries? In other words, would it still be possible to overdischarge them?
 
Hmm, that could be a good excuse to get a Spear...
However, I don't think saving a few bucks by using laptop batteries makes up for buying a 130 dollar light that I don't really need (want is a different story though...)

Where cant the L-mini be bought? I looked on shiningbeam, but it seems they don't carry it anymore. Are there any other light with a similar size as the L-mini with built in protction?
 
Yeah it seems like those 2 were bad, as they won't charge past about 3.9 volts. Is 2.7 the standard lowest voltage that 18650's should run at to avoid overdischarge, or is it different between batteries? In other words, would it still be possible to overdischarge them?
2.7V is under load; after the load is removed, the cells quickly (as in, a few seconds) rebound to 3V or higher. At a resting voltage of 3V or higher the cells aren't being harmed.

Where cant the L-mini be bought? I looked on shiningbeam, but it seems they don't carry it anymore. Are there any other light with a similar size as the L-mini with built in protction?
They should soon have it again, as far as I know.

There's the Trustfire TR-801, but I'm not sure if it has protection. However it's easy to mod, so you could replace the stock driver with one that does have protection.
 
many 18650 lights have protection circuit, the majority of them. very basic feature...
 
many 18650 lights have protection circuit, the majority of them. very basic feature...


I think you are incorrect. I have a lot of common 18650 lights including DBS, T10L, Jet IIIst, L900M, M30, DX crud, etc. None of them have protection circuits that I am aware of. :poke:

That only two or so flashlights have been listed in this thread so far demonstrates they are not so common.
 
My T10L definitely does not have protection. If you look at the specs for it, it says "Ideal operational voltage range 2V to 4.3V." Protection circuits seem to be 2.7 volts, so it is too low to have over discharge protection.
 
I think you are incorrect. I have a lot of common 18650 lights including DBS, T10L, Jet IIIst, L900M, M30, DX crud, etc. None of them have protection circuits that I am aware of. :poke:

That only two or so flashlights have been listed in this thread so far demonstrates they are not so common.
Well, my Dereelight DBS and CL1H do have protection circuits.
 
Well, my Dereelight DBS and CL1H do have protection circuits.

Well, this is a bummer for me as the circuit on my DBS V2 doesn't seem to work. Actually the Dereelight website is a little confusing on this as the DBS V3 says it has a protection circuit, the CL1H V3 make no mention and the V4 states the 3SD has protection.

I still don't think the majority of 18650 lights have protection circuits. I did just notice that the Tiablo A10 has this feature though. Hope I am wrong and the list on this thread grows, I would love to use IMR batteries for everything.
 
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I have protection in me, when light goes down, stop, thats all !
I have some unprotected 18650, i work for years with them. Most problems are only with cheap protected 18650.
 
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I think you are incorrect. I have a lot of common 18650 lights including DBS, T10L, Jet IIIst, L900M, M30, DX crud, etc. None of them have protection circuits that I am aware of. :poke:

That only two or so flashlights have been listed in this thread so far demonstrates they are not so common.

I don't think that epea deserved the poking. Wait till you have been around here for awhile before you are so critical.

Bill
 
I don't think that epea deserved the poking. Wait till you have been around here for awhile before you are so critical.

Bill

I would respectfully ask why not? I have all the 18650 lights I mentioned, and more, and none of them have proven to have an effective protection circuit. The person I poked said that "many 18650 lights have protection circuit, the majority of them. very basic feature...".

Given that all of the 18650 lights I bought are mainstream popular lights here on CPF, shouldn't at least a few of them have a working circuit if xpea was correct? Granted there are protected lights out there, and maybe my DBS should be one of them.

Maybe I haven't been here on the forum very long, but that also means you know nothing about me. I mean c'mon, is using a poking emoticon that big a deal? I haven't noticed "being critical" as being against the TOS, particularly when accompanied with an example of why I think someone is wrong. I think you need to calm down... Better yet, prove me wrong and help a "newbie" learn something.
 
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Darktort DT-E1.0 has over-discharge protection. At 3.0V it will drop into an extremely low regulated moon mode. At 2.7V it will switch off. That's one of the best implementations of over-discharge protection that I've seen imho.
 
Darktort DT-E1.0 has over-discharge protection. At 3.0V it will drop into an extremely low regulated moon mode. At 2.7V it will switch off. That's one of the best implementations of over-discharge protection that I've seen imho.

Nice! Despite not agreeing that protection circuits are currently common I am very happy to see the trend changing. I really like the IMR batteries and would use them even more as protected lights find there way into my collection. The Darktort has me hovering over the paypal button but I am hoping to hear how the new switch design is working out.
 
I would respectfully ask why not? I have all the 18650 lights I mentioned, and more, and none of them have proven to have an effective protection circuit. The person I poked said that "many 18650 lights have protection circuit, the majority of them. very basic feature...".

Given that all of the 18650 lights I bought are mainstream popular lights here on CPF, shouldn't at least a few of them have a working circuit if xpea was correct? Granted there are protected lights out there, and maybe my DBS should be one of them.

Maybe I haven't been here on the forum very long, but that also means you know nothing about me. I mean c'mon, is using a poking emoticon that big a deal? I haven't noticed "being critical" as being against the TOS, particularly when accompanied with an example of why I think someone is wrong. I think you need to calm down... Better yet, prove me wrong and help a "newbie" learn something.

Just me probably, but I saw the poking emoticon being used here as a disparaging statement. A little more critical use of it than I usually see it used. Mostly it is used in a light hearted manner between CPF'ers who know each other,, and are ribbing each other. I do apologize for my jumping on you about it, as true, I do not know you, and you probably meant nothing by it.

Bill
 
I have protection in me, when light goes down, stop, thats all !
I have some unprotected 18650, i work for years with them. Most problems are only with cheap protected 18650.
The thing is, my T10L is regulated, so the batteries will probably die before it gets dim. With protected 18650 batteries, it does not get dim at all; it simply starts flicering rapidly for a few seconds then goes out. I have a cheap ultrafire light that I have been using these batteries in, but right now I have 6 working unprotected ones, and a few other laptop battery packs laying around that i haven't removed the batteries from yet. I will probably end up with upwards of 10 batteries with one light to run them in, so I sort of makes sense to get another light to use them with (and I can't turn down an excuse to get another light). The L-mini seems more reasonable, as it is only 30 dollars and does what I need it to. However, it doesn't seem available anymore, for whatever reasons.
 
The thing is, my T10L is regulated, so the batteries will probably die before it gets dim. With protected 18650 batteries, it does not get dim at all; it simply starts flicering rapidly for a few seconds then goes out. I have a cheap ultrafire light that I have been using these batteries in, but right now I have 6 working unprotected ones, and a few other laptop battery packs laying around that i haven't removed the batteries from yet. I will probably end up with upwards of 10 batteries with one light to run them in, so I sort of makes sense to get another light to use them with (and I can't turn down an excuse to get another light). The L-mini seems more reasonable, as it is only 30 dollars and does what I need it to. However, it doesn't seem available anymore, for whatever reasons.

I am in the same boat. 12 Sanyo 18650s itching to be used. I am also waiting on shiningbeam's L-mini II.:candle:
 
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