Good LED Light for Unprotected 18650s?

[funkychateau]

I've collected a number of good (and free) unprotected 18650 cells from scrapped laptop batteries. Usually they have only one bad cell, or a circuit problem, when they get replaced at my company.

I'm looking for some good (hopefully inexpensive) LED lights to mate these cells with, for my own use as well as gifts for friends. The cells are flat-top, but I can use some disc magnets on the positive terminal if necessary.

Obviously a direct-drive or resistor-regulated light will cease to draw current (and produce light) before running the batteries flat, but I'm wondering if there are any regulated alternatives out there for one or two 18650 cells that also incorporate low-voltage shutdown. I don't really like flashlights that dim noticeably while a substantial amount of charge is remaining.

I assume that any two-cell light will be buck-regulated, but don't know which ones (particularly amongst the poorly-documented offerings from Chinese web sites) might have some sort of low-voltage warning or shutdown.

Don't ask me if I'm looking for flood or throw, I don't know but I like both. Just show me some options and tell me the details - I'll read and research them, and probably try some of each if they're cheap enough.

thanks!

 

[Hondo]

Shiningbeam's L-Mini II uses a nice, flat-regulated curcuit that will step down when the battery is getting low, from high to medium, then medium to low. I am not so sure you couldn't continue to discharge the battery too far on low, but you can only hurt the battery that way, not yourself or the light. I have a bunch of these too, and I don't get too concerned about hurting a cell, I have more.

The L-Mini II will fit the unprotected laptop cells very nicely, but can be a bit snug with some protected ones from what I hear. These come in batches, which sell out fairly quickly, and we are waiting for the next ones to come in right now. You can find Shiningbeam's sales thread for them near the top in the Dealer's section on CPFMP right now.

Also, he sells the driver board alone, which I have bought a couple of too. It is a super low-medium-high three-mode with nice wide mode spacing and very flat regulation, and mode memory. Can be used in most 18650-compatible heads and pills (in the case of a P60 drop-in).

 

[funkychateau]

Hondo,

Is this the thread? http://www.cpfmarketplace.com/mp/showthread.php?t=197812&highlight=L-Mini

I read through the first two or three pages. The raw performance looks good, but the quality control sounds bad .... that light seems to have no end of problems. For the price, I'd expect to receive "Fenix Quality" - a debugged design and maybe a tested part. Appears to be pretty good dealer response time to the problems, though.

 

[Hondo]

Yes, that's the one. Your concern is understandable. I will go from memory here, but there have been three versions of this light. The first, the L-Mini, was a 5-mode with strobe and SOS. The next, which was the first batch of L-Mini II, was the new 3-mode circuit I mentioned, and with an option for a Turbo head, for more throw. Then a "second batch" of L-Mini II's came in, with a couple of "improvements". Those are the lights which generated all of the negative feedback. Shiningbeam got the message, made good on those lights and is trying to get more of the second version, or the original L-Mini II. The circuit he is selling is the same as was used on those lights.

That may be clear as mud, but I am trying to sum up what has transpired over the past 18 months or so with these lights. I have every confidence that the next batch of these will live up to the standards of my two L-Mini II's from the original batch. I also have one of the first Gen L-Mini's.

 

[Erayd]

You could also try Dereelight - as far as I'm aware all their pills have a low voltage cutoff, and they make good quality lights.

 

[jayb79]

I have 3-4 of this type:
http://www.dealextreme.com/details.dx/sku.16516
They come in a few different versions, the brightest are single 18650 only
Search DX for WF-502B
They have all worked flawlessly, it is a low cost light but they are quite rugged.

 

[funkychateau]

I have 3-4 of this type:
http://www.dealextreme.com/details.dx/sku.16516
They come in a few different versions, the brightest are single 18650 only
Search DX for WF-502B
They have all worked flawlessly, it is a low cost light but they are quite rugged.

Thanks Jay, that's a good reference, and the light is cheap enough to grab one just for the heck of it.

I'm not familiar with the R2/Q5 debate that seemed to be raging in the online comments. What's the deal, does the R2 have lower forward voltage to make it more suitable for single-cell applications?

By one of the users' measurements that seems to show declining current with declining voltage, this light would appear to be direct-drive rather than regulated. Is this the case with your samples? Do you know if there is a review somewhere with a runtime plot?

 

[funkychateau]

OK, based on runtime plots that seem to suggest good regulation on a single 18650, plus undervoltage warning capability, I've ordered a Tiablo A7.

Still want to look into good single-cell DX lights also, though.