Battery pairing in multi battery lights

Poppy

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I cleaned out the trunk of my car recently. In it was a 21 inch traffic safety wand that hadn't been used in years. When I hit the switch, nothing happened, so I tossed the batteries.
Later I pulled out an 8 pack of Rayovac D cells that I bought as replacements for the multiple 3D lanterns I have. They were dated 2030.
I put two into the traffic wand, and it very dimly lit.
I figured there was a bad connection somewhere.

I decided to check the voltage of the batteries.
One was 1.5xx and the other was 0.4xx !
I checked the remaining 6 batteries and they were all 1.5xx volts.
So I tossed the bad one, and the wand works as it should, it is back in the trunk, ready for duty.

I know that there are those among us who diligently keep their eneloops paired for their multi battery lights. I guess the best I will do is to check their voltages before installing them.

The 2 D traffic wand is in the background.
1688777724399.png
 

Stress_Test

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I always check voltages on batteries even straight out of the pack, for that very reason you encountered. Never know when you might get a dud.

Also, as frequently as I've seen alkalines spring leaks in recent years, I don't store light with alks inside. In your case with the wand, I'd be checking it every two weeks or at least monthly, but that's just me.

Also, on rechargables (NiMH) I do the following to make sure they will perform as expected:

After they come off the charger, I let them sit for a day or two (separate from my stash of others). Then I take each one and put it into a single-cell light with the tail cap off (Quark AA R5 typically) and measure the amp draw at full power. I know a healthy AA will deliver about 1.5 amps in this case. So I hold the connection with the multimeter about 10 to 20 seconds and make sure the amp delivery doesn't sag.

If the cell passes that test, then it goes in the "ready" stash. Some of the cells that have gotten old will only deliver ~1 or 1.1 amps.

In my early flashaholic days, I really got fooled a few times by under-performing batteries. They'd charge up fine, voltage looked good, but wouldn't power the light to full brightness.
 

IMA SOL MAN

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Most of my NiMh use is in radios. Right after they are charged, back into service in the radio they came out of they go. I do use a few in Mini Mags, too, and those I try to keep paired up, too. I may rotate a pair or two, but I'm so short on Eneloops at the moment, that generally they have to go back into the device they came out of immediately, and back into service.
 

MidnightDistortions

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Usually I don't have this issue, but cheap batteries in a pack sometimes may have a dud or weaker cell. I don't have this problem with Eneloops. I like the Nitecore lights that let you know if there's a weaker cell by the switch controls flashing if it still illuminates so you either turn down the brightness or just get a better set.
 

lectraplayer

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Typically for something like that wand that will sit in standby for an extended time, I would consider putting fresh batteries in it every so often, maybe every 6 months and using the ones that come out of it for other purposes, epecially something that I will use on a regular basis. I regularly find duds that must be weeded out, including from fresh packs, so I've gotten to where I suspect them anytime I'm having power problems. ...and as often as I see batteries leak, no sense in risking your standby gear on questionable batteries.
 

Poppy

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Typically for something like that wand that will sit in standby for an extended time, I would consider putting fresh batteries in it every so often, maybe every 6 months and using the ones that come out of it for other purposes, especially something that I will use on a regular basis. I regularly find duds that must be weeded out, including from fresh packs, so I've gotten to where I suspect them anytime I'm having power problems. ...and as often as I see batteries leak, no sense in risking your standby gear on questionable batteries.
@lectraplayer this sounds like a reasonable recommendation. Unfortunately, I don't have any use for D cells, except for in lights. AND they are rarely used, so they will last for years after purchase. I do occasionally check for leaking cells in things that I have alkaline cells in, but probably not more often than yearly. Occasionally I'll find one that just started leaking, but that is actually a rare find.

A few months ago, a megaphone that was out in my shed, for the last three years, and in a non air conditioned garage for three years prior, was destroyed by alkaleeks. Usually leak damage can be repaired with a little oil and vinegar. The megaphone was a piece of crap when it was new, and after I attempted the restoration, it wasn't as good as new, so I tossed it.

For the most part I keep AAA alkalines in our remotes, because they last longer than duraloops, and they get changed out often enough that leaking is not a concern.

For the most part my duraloops and eneloops are 6 -10 years old and are self discharging. I don't know if they ever held a charge for more than a year. So I don't depend on them for long storage. I do keep them in my rayovac 2AA light that is my go to light in my car, but I top them off every 6-12 months, and I have back up lithiums.

A few years ago I bought a LiitoKala charger that will charge/discharge, and measure capacity of batteries. I never read the instructions. I suppose that I should use it to test my NiMH, and Li Ion cells, most of them are now aged.
 

IMA SOL MAN

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I recently read the thread about the member that got poisoned when his 2xCR123A light had the batteries pop. Like the other members that posted in that thread, the story scared me. Right now, I only have one light that I keep CR123As in, and that is a 3 cell SureFire. Now I keep that light in my bedroom closet--if it popped off in the middle of the night while we were sleeping, we would really get poisoned. I'm wondering if I should be checking the batteries periodically so I don't have an imbalance. What do you think? How often should I check it?
 

Toulouse42

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We on CPF know the dangers of 2 x CR123 configurations. The rest of my family have no clue so my solution was to get rid of them completely. Nowadays the only flashlights that my family have access to are either single battery or 2 x energiser lithiums or eneloops. That was possibly a little drastic but an accident that can hurt you badly can happen in the blink of an eye.
 

TIFisher

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I recently read the thread about the member that got poisoned when his 2xCR123A light had the batteries pop. Like the other members that posted in that thread, the story scared me. Right now, I only have one light that I keep CR123As in, and that is a 3 cell SureFire. Now I keep that light in my bedroom closet--if it popped off in the middle of the night while we were sleeping, we would really get poisoned. I'm wondering if I should be checking the batteries periodically so I don't have an imbalance. What do you think? How often should I check it?
I wouldn't sweat it. My 9Z sits on a shelf with 3x Surefire's in the tube (married from the same package). It rarely gets used anymore. I don't worry about parasitic drain because the light is mechanically locked out via the switch, and cell self discharge is negligible. I think I've metered those cells once in the last five years...still had matching voltages.
 

LED User

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What? CR123's can blow up and emit a poison?
Please tell me where I can read about this this.
And are there other hazards with any other rechargeables we are using?
I use an Opus BT-C3100 to charge my AA and AAA, 18650, and CR123 batteries that I use in everything from our computer mouse, smoke alarms, and half a dozen flashlights, etc.
 
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Galane

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What? CR123's can blow up and emit a poison?
Please tell me where I can read about this this.
And are there other hazards with any other rechargeables we are using?
I use an Opus BT-C3100 to charge my AA and AAA, 18650, and CR123 batteries that I use in everything from our computer mouse, smoke alarms, and half a dozen flashlights, etc.
Olight discontinued* all their dual cell (or more) flashlights some time after a man died holding one of their dual 123 cell lights in his mouth. He was not using 123 cells from Olight, so that may have contributed to the thing blowing up.

*Except the Javalot series where the flashlight body is separable from the head and tailcap, and contains more than one cell sealed within. Replacing the Javelot battery = replacing the light body. I assume the light may have cell balancing built in.

Lithium-Ion cells pack a lot of energy inside.

Years ago I read a blog post (IIRC nobody was calling online journals "blogs" yet) by someone who blew a crater in his concrete apartment balcony and shattered the glass balcony doors with a dual 18650 flashlight. IIRC he said he'd had the cells on the charger, put them back in the light and screwed the cap on. A bit later he heard a hissing, realized it was the light, had just enough time to chuck it out the open door onto the balcony and duck behind his kitchen counter. There were pics to prove it happened, including of the twisted remains of the light.

These days with cells that have built in protection against over-charge, over-discharge, and reverse polarity/charge and/or such features built into the light, or just not using more than one cell (due to big improvements in white LEDs) make it far less likely that a Li-Ion flashlight will convert itself into a frag grenade.

I do love my Javelot. Could probably mount the thing under a Cessna for a landing light. :)
 

bykfixer

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The US made CR123 cells have built in thermal runaway prevention built in. Can't speak for non US made one's though.

There was a time when one of the big battery maker companies had a meter on the alkaline where you held each end and strip along the side would glow to show how much life was left. I remember how inconsistent some of the cells were right out of the package.
 

LED User

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Right bykfixer, that was a Duracell thing. I remember that as well. In fact I still have two I need to throw out. I just looked at them. They have the same copper top, but a red body below, rather than the black body.

Wow guys, I still have an Olight I-20 that I run with 2 ICR123.
Pulling them out, they were made in China, and state "IC Protection Built In"
They're made by- AW.
I use the light only occasionally so its still basically like new.
 

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