Eneloops in single digit weather

[Rossymeister]

Hi,

Im looking to consolidate my hiking/camping bag to use AA batteries only. Has anyone had experience using eneloops in temps as low as 2F?

Right now, im using a combination of Surefire cr123s and rechargeable li-ions. They seem to work okay in the cold.

Looking to power an HDS Clicky, Yaesu Ham radio, and a headlamp.

Thanks for any input.

 

[sim1tti]

This post came up in a different thread earlier in the week. @Schokokeks seems to have some experience:

The Official Zebralight Thread .

They do, however I've never used them on high output, only medium. 18650 Zebras require a higher amp draw that two CR123 (3.5amps each) can't provide. So to be safe, I've only used medium levels. Will using high output with two CR123s be safe? I’m not sure

www.candlepowerforums.com

 

[Schokokeks]

Oh, thanks for the mention.

Yes, I've done assorted outdoor activities, and always had great results with Eneloops. Panasonic rates them down to -4*F (-20*C), which conveniently is about as cold as you're probably going spend prolonged periods outdoors (since that's -4*F absolute temp, not with wind chill).

While they're often said to work poorly in something like -20*F, many people have noticed they seem to "warm up" with use, and then just kind of function as normal. That's likely going to be dependent on the light, the emitter, the driver, where you have it mounted, the body material, etc. So test that before you get stranded in on a glacier, haha.

Off the top of my head, I think Li-ion has a similar window. On the upside, at worst, you just get less capacity in the cold, so if you bring some extras, that's not much of an issue.

Some people prefer a headlamp that has an external battery pack, as you can tuck that under a hat and/or in your jacket.

CR123A's work fine, but they're just kind of expensive, so I don't use those...or any single use cells. Many people like the lithium primary cells, too (like the lithium 1.5V AA cells), but at $3/cell and single use...hard pass.

They appear to be out of business, but I had this great AA battery holder made by a company Malamute, and I'd just keep my spares in my jacket pocket. Usually putting warm cells into a light, turning it on, and letting it run has kept it warmer than ambient temp. Plus, you tend to get reduced stepdowns in the cold, which is a fun bonus! So, I'd recommend keeping your spares "inside your warmth envelope" when possible, and then you can operate below -4F.

 

[PaladinNO]

Yes, I've done assorted outdoor activities

You wouldn't happen to have a list of some specific cells of different size (AA, 16850, 21700) that you can recommend for cold weather?

I have a small variety of lights that I would like to keep permanently in my car in case of emergencies - one of which can be the engine stalling while driving due to the cold (which once was close, at -40ºC / -40ºF) - and I would like some batteries that can at least somewhat handle that temperature.

Some light would be better than no light if I for whatever reason would have to leave the car (also I got a "ready bag" to bring with me in the car for those days in the year, which can easily include backup cells).

Used to look at Nitecore cold weather cells, but I haven't bought any and I am currently looking at Molicel M35A (18650) and P42A (21700), which says on paper to be very cold resistent.

 

[bluflaam777]

Mate! You shouldn't be out in -40, doesn't matter what letter you put after that number. *brrrrr* You Norwegians are a special breed LOL

I can only add that you shouldn't charge cells when they're frozen. Using them below freezing is OK, but at -40 I don't know. They may lose some efficiency/life.

 

[Schokokeks]

You wouldn't happen to have a list of some specific cells of different size (AA, 16850, 21700) that you can recommend for cold weather?

I have a small variety of lights that I would like to keep permanently in my car in case of emergencies - one of which can be the engine stalling while driving due to the cold (which once was close, at -40ºC / -40ºF) - and I would like some batteries that can at least somewhat handle that temperature.

Some light would be better than no light if I for whatever reason would have to leave the car (also I got a "ready bag" to bring with me in the car for those days in the year, which can easily include backup cells).

Used to look at Nitecore cold weather cells, but I haven't bought any and I am currently looking at Molicel M35A (18650) and P42A (21700), which says on paper to be very cold resistent.

A shortcut you can do is, if it's REALLY COLD, is stick the battery in your jacket and let it warm up, then pop it in and it should be fine. You can essentially use almost any cell if you do that.

Most cells, below -20*C are going to have a dropoff of performance. Nitecore makes a battery bank that has warmers installed on it (like EVs have), so that is likely a good bet if you have a light that takes external power.

Technically, Eneloops lose even less energy when stored in the cold, so as long as you pop one in the pocket before using it, you've got a bit of a cheat code, there, haha.

That's how I'd do it, and I carry a Skilhunt E2A with an eneloop daily in winter (so I always have a spare, warm eneloop).

Of course, you can also just store more batteries than you think, and accept they won't be at full capacity.

Generally, though, Lithium PRIMARY cells (AA, CR123A, etc.) are rated to -40F/-40C, so those might be your go to for an emergency, AND they hold their charge in storage for a decade, which makes the few Krone per cell not as hard to swallow.

 

[PaladinNO]

A shortcut you can do is, if it's REALLY COLD, is stick the battery in your jacket and let it warm up, then pop it in and it should be fine. You can essentially use almost any cell if you do that.

Technically, Eneloops lose even less energy when stored in the cold, so as long as you pop one in the pocket before using it, you've got a bit of a cheat code, there, haha.

Of course, you can also just store more batteries than you think, and accept they won't be at full capacity.

So keep some batteries on me, and enter Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start. Got it. ^^
Damn, I had honestly forgotten about that trick. Thanks for the reminder.

Thank you, it sounds like I should be fine then. I got several lights attached on my daily backpack, and that is on the passenger seat all the time, and is getting warmed up while driving. Same with the lights I keep in the car.

And running the lights on medium output due to reduced capacity is fine. I would much rather have some light than none at all.

 

[Schokokeks]

So keep some batteries on me, and enter Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start. Got it. ^^
Damn, I had honestly forgotten about that trick. Thanks for the reminder.

Thank you, it sounds like I should be fine then. I got several lights attached on my daily backpack, and that is on the passenger seat all the time, and is getting warmed up while driving. Same with the lights I keep in the car.

And running the lights on medium output due to reduced capacity is fine. I would much rather have some light than none at all.

Yeah, a lot of people think that code only works on the Galuga archipelago. Nope. Chuck Tes...I mean, nope, it works anywhere on earth!

Sounds like you're set. If You REALLY wanted, keep something in the glovebox with a CR123A or Lithium AA primary as a backup, backup, but if I probably just use some masking tape to wrap a pair of Eneloops together, and stick them in a pouch in the backpack, and you've got a day or two of light on most medium modes, all together.

 

[PaladinNO]

If You REALLY wanted, keep something in the glovebox with a CR123A or Lithium AA primary as a backup, backup, but if I probably just use some masking tape to wrap a pair of Eneloops together, and stick them in a pouch in the backpack, and you've got a day or two of light on most medium modes, all together.

I think I am good. I haven't been on any longer trips in years, where packing extra cells would make any sense. But I have already bought portable carriers (actually meant for storing individual 12 gauge shells, but fits 18650's perfectly) for attaching to my backpack if I need it. 🙂

What I have in the car while driving is at the moment this:
Permanently in the car:
Streamlight PolyTac (16650 / 2x CR123)
Sofirn SP40 headlamp (18650)

With me, belt or pockets:
2x Nitecore TIP (built-in battery - got one on each car key, and I got both with me due to a fault in the driver side door lock)
Wurkkos FC11C (18650)

Attached to the backpack (which is with me everytime I drive anywhere):
Sofirn IF23 (21700)
Sofirn SF16 (18650)
Phone LED
(and there is no reason NOT to put a Fenix LR35R in one of the molle pockets I've recently hooked onto it)

Honestly, if I need more than this for just illumination on my commute, in the worst case scenario, I would need a light where I can program one of the special modes to change the SOS to RIP. Because I would be out of food and water long before my last light would be out of power.
And if I got my winter ready-bag with me too, I got a 30.000 mAh powerbank in it. Which also has a built-in LED-light.

Call it 50 % reduced capacity due to cold weather, and that's still ~10.000 mAh of capacity on low-medium light output. ~25.000 mAh with the powerbank.

But I do need some more 18650's for my latest light purchases (and there will be more), and I planned to buy some extra Molicel M35A (I keep mixing that name with M41A...) to have some spares. And some Molicel P42A 21700 to try them along my Samsung 40T.

 

[Schokokeks]

Another option is (I assume they're available in the EU) are these GooLoo brand "jumpers" for your car. They're essentially a Lithium ion power bank that has the cables to connect to your car battery, and they can jump enough amperage to turn the engine over.

It's a very cool winter emergency thing to keep in the car if you live in a cold place. You just stick it in your jacket to warm it up before using it, and it's awesome (It will also warm up VERY FAST the first time you use it, even though it won't work, but it'll generally crank over on the second go once it's warm). It can also be used as a regular powerbank.

Project farm has tested a bunch over the years, and a lot of these are essentially the same brand, but I'd picked up one of these for maybe $80 from Wal-Mart years ago, and it's absolutely gotten my engine started on days that dropped below -20*F (-29*C) when my couple-of-years-old battery wouldn't crank the engine over (I replaced my battery after having had to use this, haha):

If it turns over an old diesel tractor, whatever you drive is probably fine, haha.

 

[Monocrom]

I would never trust rechargeable anything as my only source of power for lights. Especially those used for backpacking or hiking. Yes, you can use rechargeable AAs.... But bring along a good, sealed pack of AA alkalines in case you need them.

 

[Schokokeks]

I would never trust rechargeable anything as my only source of power for lights. Especially those used for backpacking or hiking. Yes, you can use rechargeable AAs.... But bring along a good, sealed pack of AA alkalines in case you need them.

Really? Still, in 2025? I could see that maybe 20 or 30 years ago. Eneloops hold a charge for years on end, and Li-ion cells hold a charge for a pretty decent time, too.

For me, I feel WAY more comfortable recharging cells before I go out. I'd sure hate to count on my primary cells, only to open them up and discover some manufacturing or storage defect has rendered them junk.

I've never run into a major issue with a rechargeable cell in decades, whereas I've definitely had more than one dud and/or failure with primary cells. I feel way better that I can verify a rechargeable cell is good before I need it.

I wonder if being a gun owner colors my view here, because with guns, you NEVER trust things until they've been tested, and you kind of assume ammunition will be your primary source of failure, as it's impossible to test beforehand, and it's a single-use item. For me, primary cells fit into the same nebulous "mystery reliability" as ammunition; you'll never know 100% if it works when you need it, so be prepare for failures.

 

[Monocrom]

I'm probably one of the oldest CPFers to make the switch to rechargeables in my primary EDC lights for one simple reason, up until about 2 or 3 years ago, I tried making the switch numerous times before. Miserable failure each and every single time! To a ridiculous degree! Finally, battery prices for CR123 primaries got too high. Even if you knew the tricks to getting great deals on them. (Buy online, in bulk, from a trusted seller.) So, gave it one more try. Finally encountered some reliability. To the point I could live with. 20 or 30 years ago?? More like 2 or 3 years ago.

Except for the rare leak, never had a single issue with an Alkaline primary of any sort not working properly. Toss them in, they work! But yeah, even nowadays I still prefer using lights that run off a single 18650 instead of a single 21700. Why? With an 18650, almost every single such flashlight will take two CR123 lithium primaries if needed.

 

[bluflaam777]

I have "known good" alkaline cells try to ruin my flashlights. They were OK and then within days (not a hyperbole) leak. 🖕 those cells as backups.

lithium primaries. All fine. Rechargeable of any sort has been OK fine. (granted I don't use/store in extreme conditions) Brand/storage/usage/age etc all play a part in value per $ and value per need

 

[Schokokeks]

I'm probably one one the oldest CPFers to make the switch to rechargeables in my primary EDC lights for one simple reason, up until about 2 or 3 years ago, I tried making the switch numerous times before. Miserable failure each and every single time! To a ridiculous degree! Finally, battery prices for CR123 primaries got too high. Even if you knew the tricks to getting great deals on them. (Buy online, in bulk, from a trusted seller.) So, gave it one more try. Finally encountered some reliability. To the point I could live with. 20 or 30 years ago?? More like 2 or 3 years ago.

Except for the rare leak, never had a single issue with an Alkaline primary of any sort not working properly. Toss them in, they work! But yeah, even nowadays I still prefer using lights that run off a single 18650 instead of a single 21700. Why? With an 18650, almost every single such flashlight will take two CR123 lithium primaries if needed.

It's always interesting how, because we only have our own small samples, we can end up with opposite experiences, haha.

I guess, to be fair, I mostly use Eneloops. I have Li-ion cells, but they're not the bulk of my batteries. I very much like that Eneloops can be charged and just stored in a light for years on end. I have some very occasional use Maglites with Eneloops, and they've been in there for...probably 5+ years, haha. They still work for the few seconds I need them in that area. If I'm going out for a walk or something, I'll either bring a spare Eneloop or two if I don't feel like recharging one in advance. Slipping a small case in a shirt pocket, or taping two together with masking tape is easy enough, and takes almost no space.

Mostly, I'm just really frugal, so the fractions of a cent per charge is just the bee's knees over their decade-or-so lifespan, haha.

 

[leeholaaho]

I would never trust rechargeable anything as my only source of power for lights. Especially those used for backpacking or hiking. Yes, you can use rechargeable AAs.... But bring along a good, sealed pack of AA alkalines in case you need them.

What are alkalines😀

 

[PaladinNO]

I would never trust rechargeable anything as my only source of power for lights. Especially those used for backpacking or hiking. Yes, you can use rechargeable AAs.... But bring along a good, sealed pack of AA alkalines in case you need them.

Wow, I am the complete opposite. I would definitely not trust a pack of alkalines. Knowing me, I would end up not using them and ultimately forget about them, only finding them randomly after 8 years, where half have leaked and ruined the other half.

That said, depending on the situation, I wouldn't trust only a single or a pair of rechargeables either. I would bring additional known good, recently recharged spares, and double the amount that would be in use. And if it would potentially be critical that the batteries work, I would also bring a battery bank.

If I may ask, how many rechargeable batteries would you bring, to reliably last you whatever duration you expect to need them?
Aren't Eneloops rated to hold a charge for years, if stored properly?

I'm probably one of the oldest CPFers to make the switch to rechargeables in my primary EDC lights

But yeah, even nowadays I still prefer using lights that run off a single 18650 instead of a single 21700. Why? With an 18650, almost every single such flashlight will take two CR123 lithium primaries if needed.

Sounds like me and my switch from CRT- to LCD-monitors at the local LAN-parties. I was the second to last to make that switch in 2007. ^^

I agree with you on 18650 vs 21700, but for a different reason. Technically, I would say 21700 every time due to higher capacity, but practically...ready-made boxes for carrying spare (protected) 18650 cells are easily available to me, but I have not been able to find the same for protected 21700 cells.

 

[PaladinNO]

What are alkalines😀

You know every AA / AAA cell that cannot be charged, and does not say 'Eneloop' on the wrapping? That's an alkaline. ^^
I haven't touched those things in years. 🙂

 

[Rossymeister]

Thanks for the input everybody. I got everything switched over to AA in my hiking bag. Ill update if i have any problems.

 

[RWT1405]

I would never trust rechargeable anything as my only source of power for lights. Especially those used for backpacking or hiking. Yes, you can use rechargeable AAs.... But bring along a good, sealed pack of AA alkalines in case you need them.

I agree with you right up to the use of AA alkalines in my flashlights

Instead, I use Energizer Lithium AA's

I am slowly beginning to use rechargeables in some primary use flashlights, but always have CR123's or Lithium AA's with me, as back-up

I still continue to use only CR123's and Lithium AA's in flashlights kept in my vehicles, work bags, BOB's, etc..