I’ve got 500+ cr123 batteries. What are some good flashlights that use them?

VeritatisVox

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A couple of years ago I responded to a Craigslist ad offering "lots of cr123 batteries for free". Turns out it was a research team at MIT that used them in a submersible research vehicle (a submarine). The batteries powered a low-draw component of the communication system, but for safety purposes they replaced the batteries after every dive. They have 95% charge remaining but the team would risk a very expensive sub on batteries that weren't brand new.

so now I have a big box with a zillion of these batteries. I'd like to find some good flashlights to use them with. Ideally I'm looking for something very high powered (think Cree XHP 70.2), something good for walking the dog, and something good for the glove box or emergency kit.

it's been a while since I was really keeping pace with flashlight gets and I know the technology has evolved a lot over the past decade, so any suggestions would be a big help.

thanks!
 
Plenty of choice from Malkoff MDC line that take this cell, single or multiple depending on your needs.
 
The problem is, that flashlights that use CR123 cells are generally designed to be sold to government, like law-enforcement, etc. They're expensive, and usually under-powered compared to lithium-ion equivalents. But the clients don't want to be bothered with recharging, so using disposable cells makes sense, even if they aren't the best option for enthusiasts.

10 years ago, CR123 flashlights made sense for flashaholics. Nowadays, not so much. You'll get more output and longer run-time in lights that are designed for 18650 lithium-ion batteries.

IMO, I wouldn't buy expensive lights (which all government lights are, because they'll pay it) just to use up some old CR123's you don't have a use for. But I might get a light that uses a wide range of voltages, such as 2.8v - 6v, and use the CR123's (maybe with a swapable battery holder) as a back-up to 18650's.

CR123's will work in extreme cold (down to -40 degrees), so they do have a niche application. Lithium-ions will die very quickly in that kind of cold. So, military or law-enforcement might still have a need for them, even if recharging was an option.
 
Are you certain that all the cells were drained at the same time, at the same rate? Are you certain they all contain the same capacity and voltage reading? Because if not, then I don't believe sticking a bunch of randomly discharged CR123's in series into lights, especially one's with the kind of current draw we have nowadays, is a very good idea. I would expect our members to know better, rather than give out dangerous advice like that.

I recommend using them in single cell lights, where there is no danger of having mismatching cells. The market is flooded with single CR123A lights, but keep in mind many, like the Acebeam TK16, require a Li-ion cell in order to achieve max output.

Funny that Li-ion gets such a bad rep for being dangerous (they are, not undermining it), when it's the Lithium primary cells, especially when mismatched and run in series, that are the really scary stuff.
 
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Make small 'lots' of cells within .1V for starters.

...then find a light like the SX25L3 on closeout & ceiling bounce it for your home lighting needs.
(and start giving some away.)
 
If he knows that they are all at 95% and we're all used the exact same way then he knows to check voltages or at least I would assume that. Assumptions do get people in trouble though. I agree with batching out the batteries. I assumed OP would know to do that
 
I have a big box with a zillion of these batteries. I'd like to find some good flashlights to use them with
I do not recommend using lights that take more than 1 battery unless you really know they are voltage matched.

It is imo, far safer to use lights with only one battery.

There are many many options in single CR123 lights. Some of my favorites, that are available off the shelf today, are:
Jetbeam RRT-01
Nitecore EX11.2
Olight S1 Mini Baton
 
A good thought about single-celled fixtures, although I and my friends and I have never encountered problems mixing them, but these were not very powerful lamp lights SF M4/M6.

As I understand it, there is no point in saving energy, then good one of this, depending on what type of beam is required: Elzetta Alpha, SF E1B, Malkoff MDC HA SHO or CR123 body with head E1 / E1 Hyper Throw - in maximum modes they will drain your batteries in about 25-30 minutes.

By the way Jetbeam RRT-01 which jon_slider mentioned, can be modified with a more powerful diode and get a very good thing. Exist are 3 volt versions XHP50.2 it's nice beam and very bright
http://kaidomain.com/Flashlight-DIY...e-XHP50_2-K2-1C-White-6000K-6500K-LED-Emitter

https://www.youtube.com/watch?v=uXdc1JHTSLE
 
I do not recommend using lights that take more than 1 battery unless you really know they are voltage matched.

It is imo, far safer to use lights with only one battery. There are many many options in single CR123 lights. [...]
+123 on the above, lol.
I don't even have complete faith in attempting to voltage-match cells from mixed lots - just too many possibilities for different discharge behavior throughout the inventory; reverse-charging, & kaboom.

Risks are low overall yes, but risk should be balanced with reward; what is the reward by making significant revisions to a previously-sound flashlight repertoire just to make the most use of free cells?

(Another consideration is that the cost of a single dedicated flashlight is comparable to a complete LiIon setup.
If the LiIons are well monitored, they will end up being more reliable IMO & can last an exceedingly long time.)

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Risks will also go up with drain rates; high-drain applications can overheat CR123's, pressuring a marginal cell into becoming an unstable one.
For high drain rates, a quality IMR cell is exceedingly reliable and very economical over the long-term.

Another reason I like LiIons is that once a cell has been cycled a few times, it can be considered pretty trustworthy; who's to say that the 'next' CR123 cell won't be defective or even marginal ? Defective or marginal by itself, no problem; but once in series in a larger flashlight, can make for a much larger problem.

There are great 1xCR123 configs out there; my two choices are the relatively thirsty single-cell Malkoff M31, and the SureFire L1.

-----

In short; yes I would be all over an inventory of free CR123's. In fact I was the recipient of qty.100 partially used ones many years ago; I gave away something like half, and used the other half in various single-cell SF's. But please keep in mind that they did become less reliable when they got to their ~10-yr age dates.
 
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For sure drain rates is a very important factor.

Higher voltage setups (9V or more) draw much lower amps to get your watts,
as compared to a single or even double cell, screaming for mercy.

I picture 15 years ago guys w/ cr123 power trying to push 300W for a incan setup:poof:
 
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A couple of years ago I responded to a Craigslist ad offering "lots of cr123 batteries for free". Turns out it was a research team at MIT that used them in a submersible research vehicle (a submarine). The batteries powered a low-draw component of the communication system, but for safety purposes they replaced the batteries after every dive. They have 95% charge remaining but the team would risk a very expensive sub on batteries that weren't brand new.

I have a friend who is a surgeon with a similar supply of lithium primary AA cells. He uses them in battery powered orthopedic surgical tools like drills and saws. By local procedure they can only be used once and then 'discarded'. The patient is billed $40 a cell :eek:, insurance pays the contracted in-network rate of $3 a cell and the hospital takes it.
 
You can find an hds for a decent price, used. This is the reason cr123 batteries were invented. Built like tanks and tuned around the cr123 battery, you will probably use the whole supply before you need another one
 
Lots of good suggestions here (especially the part about single-cell use only)

I use a Peak Logan for most of my partially-discharged primaries.

With the way Peaks are (semi-)regulated, any substantial quantity of CR123A will last, to a first approximation,... forever :candle:
 
A CR123 can be used in a Nitecore EX11.2 to produce

lowest 0.02 lumens
highest 150 lumens

llUBnfrl.jpg
 
If you could use a headlamp, the Fenix HL50 can use either 1xCR123a, or, using the included extender, 1xAA, and the led has a neutral tint. Although I have lights that use mutiple cells, in your particular case, I agree with those that suggest that a single-cell light might be the way to go.

It would be a challenge to use up that many cells in 10 years!
 
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Man, one-at-a-timing on 500 cells in efficient lights will last you a lifetime. If you could be reasonably certain the cells are well matched, it would be fun to look for a beater SF M3, M4, or M6 just to use for kicks and burn though cells having a good time.
 
Man, one-at-a-timing on 500 cells in efficient lights will last you a lifetime. If you could be reasonably certain the cells are well matched, it would be fun to look for a beater SF M3, M4, or M6 just to use for kicks and burn though cells having a good time.

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For sure,,
people have to stop being babies, cells within .01~.09V are plenty close to actually have some fun.

I do stuff w/ LiPo batteries that generate huge amps and actually have 'balance' leads to ensure voltage is similar.
After using them VERY hard and checking the voltage , they can be .2~.3V difference in a multi cell config, again after being pushed really hard.
Yes a different chemistry, but you have to understand, they are being used well over 50A.

Put a few of the cr123s' of same voltage together & enjoy light funnessss

== With all the Li-ion & LiPo batteries I have, I'v never had a single problem
 
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Man, one-at-a-timing on 500 cells in efficient lights will last you a lifetime.

Maybe, if you're willing to use most of their capacity. (Or maybe not, if you're a heavy user.)

The problem with disposable batteries, is that they're almost never fully charged in your flashlight. Unless you know they're almost fully charged, you can't really take the light out on a long walk, unless you replace the batteries with new ones. You can use the light around the house, for short periods of time, but again, unless you know the batteries still have a good supply of energy left, you can't really depend on the light if you need it. Battery indicators help, but don't really solve the problem.

So, you're stuck throwing away disposable batteries well before they're drained. Or, you use them in a battery vampire, just for fun.

With rechargeable batteries, you can top them up after any significant use, so your flashlight is always ready-to-go.
 
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