How often to replace batteries siting in surefire?

Lester1965

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I have a Fury, X300, tlr1, and some scout lights that aren't used but sit with batteries in them. How often should I change them?
 

hamhanded

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10 years if you believe in expiration dates. But if they're not critical lights, just replace them when they don't work anymore. I have surefire CR123s from the mid 2000s that still seem to work fine.

Something changed with Surefire's CR123 chemistry over the years, though-- they smell different. I know, that's a weird thing to observe, but there it is. I don't know what it means for their performance. Probably nothing at all.
 

knucklegary

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That sweet ether smell from lithium batts, we get a whiff when opening tailcaps.. Don't make a habit sniffing that into your lungs. Leave that for the vape crowd to enjoy

@Lester1965, on flashlights stored, I loosen tailcaps to where there is no contact, just as precaution to make sure no drainage
 

bykfixer

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The only issue I think about when storing CR123's in a light for years is a gradual self discharge that may vary battery to battery. Especially non US made batteries that may not have been built with a thermal runaway protections. When in a series of say two or three, if one has a much lower remaining voltage than another, the cells try to balance each other out, the higher voltage one(s) trying to charge the other one(s).

Ordinarily this is not an issue, but it is a distinct possibility. If you feel the light getting unordinarily warm shut it off and remove the batteries, prefrably outdoors or in a well ventalated environment.
 

sween1911

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#1: Always write the installation date on primary batteries when you replace them, I like using the oil-based Sharpie Paint Pen. Both the CR123's in your Scout Lights and the coin cells in optics.

#2: For standby items, check them periodically. Hit the buttons, give it a few seconds and make sure it stays bright. How many times have you done a quick check, looked bright, then went to use it for a few minutes and it fizzled out? It's never a waste of time to take the batts out, give them a look, hit them with a digital voltmeter and get a good read on the voltage. If they're both not good, or if one looks low, especially in a two-cell stack, change them.

I'd say if they test good and are still bright but your date is over 2 or 3 years, swap them out. For serious usage lights, if you're taking classes and training regularly and running your lights frequently, you'll want to keep a closer eye on the batts. You might go so far as to maintain a set of fresh batts for ready storage, and a set for training. As you rotate them out, put them in a Ziploc bag in your range bag for training. Don't mix batteries of uneven voltage. Simple digital voltmeters are so cheap and ubiquitous, you could keep a little one with your training gear.
 

hamhanded

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Does storing them in the light cause them to last less years?
Only if there's parasitic discharge caused by the light. I'd be wary of e-switches for this reason.

The only issue I think about when storing CR123's in a light for years is a gradual self discharge that may vary battery to battery. Especially non US made batteries that may not have been built with a thermal runaway protections. When in a series of say two or three, if one has a much lower remaining voltage than another, the cells try to balance each other out, the higher voltage one(s) trying to charge the other one(s).

Ordinarily this is not an issue, but it is a distinct possibility. If you feel the light getting unordinarily warm shut it off and remove the batteries, prefrably outdoors or in a well ventalated environment.
Yeah this is a good point, I've mostly stayed away from 2xCR123 lights for this reason. Too many reports of unbalanced voltage causing voltage inversion and blowing up.
 
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aznsx

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I'm doing some catching up on things and just happened to re-read part of this thread, and thought it a good idea to bring out a pair of related points which could be overlooked by some; one which was at least partially overlooked (or not fully appreciated) by me until now.

When in a series of say two or three, if one has a much lower remaining voltage than another, the cells try to balance each other out, the higher voltage one(s) trying to charge the other one(s).

I understand that most will already be aware of this first point I'm highlighting, so please don't feel insulted by my pointing it out, as some might not be. If there is any 'balancing' or equalization of potential (voltage) between series-connected cells, it is a fact that such cannot occur when the series circuit is 'Open' (not completed). To the extent that it may happen, that can only occur when the series circuit is completed, which in the case of most conventional flashlights is when 'the button is pushed' / the light is turned on. To the extent that this equalization occurs, and given that such imbalance of cell voltage / potential has been suggested as a cause of out-of-bounds conditions leading to catastrophic failures or risk / danger to the user, this would mean that such a condition cannot occur in storage when the light is turned off. It could only occur following activation / 'switching on' of the flashlight.

Now that's a reassuring conclusion, isn't it....? This means that if such a catastrophic event occurs, which some would attribute to unequally charged series lithium primary cells in a flashlight. such will never occur when the light is sitting in a drawer unused. It will only occur when I grab the light and turn it on to use it, and thus while it's in my hand. The light will never blow up while I'm asleep, it will blow up in my face. I find that very reassuring indeed:)
 

thermal guy

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Grab a volt meter. They should be 3.2 volts. 3.0 volts and they are getting old. 2.8 time to change
 
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KITROBASKIN

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Speaking of freak accidents, thoughtful storage of loose batteries is important so as not to unintentionally complete a circuit resulting in saddening family and friends with your painful demise.

Are there protections against that in quality CR123 cells?

Many of us have unprotected batteries. Those would be painfully embarrassing (at best) to mistreat.
 

BillBond

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Replace then when the voltage gets low. I have had 10 year old Surefire batteries work fine.
 

aznsx

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BTW, just to clarify regarding my earlier post in which I was joking about a light 'blowing up in my face': I think such catastrophic failures resulting from mis-matched CR123A cells in series, while they have occurred, are extremely rare, and not something I lose any sleep over. Such failures are likely almost completely avoidable by simply using 'best practices' / due diligence (as others have mentioned), and in that case should only be a risk when there is a fundamental problem with a cell (which one might not catch just by using 'best practices'), and that itself is likely even more rare. Now for those who may throw partially used 123s in a drawer and just grab some randomly to use in a light, well, for such people there just are no good answers:).
 

bykfixer

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The US made CR123 cells have a built in thermal runaway protection so that they won't explode. Don't know about those made elsewhere. But it's pretty safe to say SureFire batteries are fairly safe.
 

Monocrom

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Nice thing about lithium primaries is that you can leave them in a light for years without any fuss.
 
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