Do you keep your batteries in your multiple cell Li-Ion lights?

Guitar Guy

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I did find some old threads with some folks detailing how they checked for parasitic drain with removing the tail cap and testing with an ammeter, but I'm not really going to get into all of that.
 

letschat7

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@letschat7, that looks pretty nasty, but 20 years is a pretty long time. I think my oldest Li-ion cells are about 7 yrs old. I've only ever had one fail, and it just pretty much went dead all of a sudden. I think the protection circuit may have failed. There was no venting or event. When I tested it, nothing registered at all, so I got rid of it. I believe it was a Nitecore 18650. All of my Li-ion batteries are protected Fenix & Nitecore, and a few Acebeam & Imalents that came with the lights. Most of them have not really been charged very many times.
I bought it thinking it was usable went to charge it and was like fuuuuuuuuuu.
 

PaladinNO

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I keep all my lights loaded, but I equally keep the cap slightly unscrewed on all of them to prevent any parsitic drain, which most of my lights unfortunately have. And I do it on everything from my single-cell to the dodeca-cell (12-cell) lights.
 

vicv

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What exactly is the fear here leaving cells in lights in series specifically?
Is it worse to you than a single cell? Why?
As far as parasitic drain, why is it a worse issue in a multi cell light?
And on parasitic drain, if your light has an electronic switch, it has it. If it's a mechanical switch, it doesn't
 

Guitar Guy

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What exactly is the fear here leaving cells in lights in series specifically?
Is it worse to you than a single cell? Why?
As far as parasitic drain, why is it a worse issue in a multi cell light?
And on parasitic drain, if your light has an electronic switch, it has it. If it's a mechanical switch, it doesn't

This thread is a couple of months old, and my question pretty much got answered.

The reason for the question about multi cell lights was regarding if a light sat around for 6 months or a year without getting used, could there be a danger of one cell failing or rapidly discharging way more than the other(s), and would it cause the other cell(s) to try to charge the failing one, and somehow cause a safety hazard. If that were the case, I had wondered if it would be safer to remove cells from lights that seldom get used.
 

vicv

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Ah. Ok. Already answered then but ya, no issues. One cell cannot charge another one when they are in series, so no issue there. And if there is no parasitic drain, also, no issue. But in my opinion, if you were going to leave a light, unused for that long, I would take the cells out. Only so I can put a storage charge on them so they will not degrade.
 

PaladinNO

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My bad, sorry. Didn't mean to necro anything, this thread just showed up in the "similar thread"-feed, and I misread the month.
 

Monocrom

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Honestly, sitting around for 6 months to a year unused; grab your charger and top off those rechargeable cells before using the light.
 

Guitar Guy

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Honestly, sitting around for 6 months to a year unused; grab your charger and top off those rechargeable cells before using the light.
Yes, I do, but most of them do get used a little here and there. It's just that I have a lot of lights, so I try to use most of them a little in order to keep cycling the batteries, but it takes quite a while before they actually "need" to be charged.
 

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