# Lithium Ion below freezing temperature performance



## jzmtl (Jan 13, 2009)

When I went to ski last weekend, it was -18C (0F). I had my cellphone in an outside pocket. About an hour into skiing it started low battery beep. I just charged it a day in prior, so I suspcted it's because of the cold temperature. When I went inside to take a break, the charge level indicator shows red empty. After it warmed up, I restarted it and now the charge indicator shows full charge (which was later confirmed because recharge after I got home was done quickly) . 

So my question is how much is lithium ion cells affected by temperature? -18 isn't that cold (well for people in the north anyway). I have a zebralight h60 on order too which will be used outside, and if li-ion suck that much already at this temperature it's definately not good since the whole thing is exposed with no way to insulate. :duh2:


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## Pöbel (Jan 13, 2009)

have been using an AW on my bike @ -19°C, no problems. Capacity seemed to stay within normal levels.


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## VegasF6 (Jan 13, 2009)

There have been several threads on performance at low temps, or at least I thought. But, anymore I just check what battery university  has to say. 

*Lithium-ion* works within the discharge temperature limits of -20°C to 60°C (-4°F to 140°F). The performance is temperature based, meaning that the rate capability at or below -20°C is reduced due to the increased impedance of the electrolyte. Discharging at low temperatures does not harm the battery. Lithium-ion may be used down to -30°C (-22°F) with acceptable results. Larger packs will be necessary to compensate for the reduced capacity at these temperatures. 

Doesn't say just how much performance will be decreased, but the good news is you aren't doing any permanent harm to the cell apparently. 

Have read a couple threads about keeping cells in the freezer and it seems the answer was don't, you would damage them, but that seems to contradict this. Most home freezers are operating somewhere between 5 and 30 farenheit, right?

This doesn't address the protection circuit, but I don't imagine that a solid state device would be harmed, unless maybe there is a mechanical change, like flexing or something?


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## balou (Jan 13, 2009)

VegasF6: electrolytic capacitors have fluid in them. they could be permanently damaged if frozen (as ice usually has greater volume than fluid)

but cellphones didn't have electrolytics in them for years now - they're just to big. I dunno about the various lights though.

jzmtl: keep your light inside your clothes until you need it - the batteries have some time to cool out. and then just hope that the waste heat of the light will keep them reasonably warm. Or just rotate two batteries - use one while the other warms up.
I do this in winter when shooting with my DSLR. I keep the battery under my jacket just until I need it, then after shooting I immediately put it back. (by the way, the fact that the camera itself is cool is an advantage - most of the sensor noise is thermal, so you get lower noise in winter)


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## ltiu (Jan 13, 2009)

Curious.

I know when using batteries, the thing heats up because some of the energy is lost as heat.

So then, will the process of using a battery result in the battery capacity increasing or voltage and current increase the more you use it because more heat is generated and the battery gets warmer and warmer?

This assumes the battery heats up more than is being lost to the cold air.

I would then think that if you have a flashlight that draws a lot of power from a battery, then the heat generated will result in the battery giving more power as the light is left on longer.


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## Buck91 (Jan 14, 2009)

I've noticed a lower capacity in various li-ion and lipo batteries both on my bike (rcr123 and 14500 li-ion) and my cell phone (li-po) when used in cold weather. These effects start becoming noticable around freezing (32F) and by the time you get down to zero are quite pronounced.

This is all empirical observation without any technical data to back it up. But I've had much better luck with quality NiMH cells holding their charge during cold weather.


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## Therrin (Jan 17, 2014)

A couple weekends ago I went camping in NW Wisconsin. There was a few feet of snow on the ground and the one day it actually warmed up to -20*F (-29*C). 
At night it was closer to -40*F(this program says -40*F = -40*C...wierd), on the day it only warmed up to -25*F, the windchill was -52*F.

On the day it was -25*F, I was slogging through some snow when my phone rang. After pulling it out of various layers I noticed it had 3/4 charge. After talking for about 6 minutes it went dead in the middle of the call; and I couldn't get it to start back up. I later warmed it up in my sleeping bag while I was (trying to) sleep, and then it worked fine.

That night my headlamp was running at a significantly decreased rate (running on my 1S2P custom 18650 pack with 2x2200mAh cells), but didn't die completely. High mode only draws 1amp (R5). 

I had a number of ICR18650H 2200mAh cells with me, a 15.6Ah Limefuel, a ICR26650, my cell phone, and some SolarForce 2600mAh cells. At one point most of those were in my backpack, which was at the lower camp site; their heater ran out that night and everything in that location thoroughly froze solid (and the people staying there left that night). It was somewhere around -40*F/*C that night, give or take a few degrees. 
The next day when it was -25*F, those of us at the upper camp site said "screw this" and hiked back out further up to the vehicles, and came back a week later for the gear we had left at the lower camp site.

I let everything thaw out slowly, as it had spent a week in some pretty bitter cold. My limefuel works just fine, as does my phone and most of my other cells.

The only problem I've noticed so far is with my ICR26650 cell (4000mAh). When I checked it later at home, it wouldn't run my SST50 on high output; and it was only showing 3V when I pulled it out and checked it, but had barely been used on the trip. After giving it several days to warm back up, I tried charging it. It was drawing a continuous high amperage for a couple hours but the voltage was still very low when I checked it. It didn't seem right so I pulled it off and it's been sitting for another week. Now it's showing 3.6V again and works fine. :duh2:

Perhaps when it deep froze at -40* it just took a lot longer for something inside to thaw out because it's a larger diameter cell? Not sure what the exact issue was.

I'm heading out to MN tomorrow for a week and will be using many of my lights extensively throughout the week. I think the high temp is supposed to be 15*F or 18*F; so I'm making some extension wires for my packs so I can keep them under my layers while my headlamp is in use on my helmet.


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## markr6 (Jan 17, 2014)

I always had the habit of sleeping with electronics when backpacking in the cold. Then I remembered people storing batteries in the freezer or refrigerator, so thought maybe I don't need to go thru this effort.


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## LEDAdd1ct (Jan 18, 2014)

-40 degrees C and -40 degrees F are equivalent.


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## inetdog (Jan 18, 2014)

markr6 said:


> I always had the habit of sleeping with electronics when backpacking in the cold. Then I remembered people storing batteries in the freezer or refrigerator, so thought maybe I don't need to go thru this effort.



But they generally give them time to warm up before using them.

Sent from my XT1080 using Tapatalk


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## Curious_character (Jan 18, 2014)

balou said:


> VegasF6: electrolytic capacitors have fluid in them. they could be permanently damaged if frozen (as ice usually has greater volume than fluid)
> 
> but cellphones didn't have electrolytics in them for years now - they're just to big. I dunno about the various lights though. . .


The freezing temperature of the liquid in electrolytic capacitors and batteries is much, much lower than the freezing point of water. I've dealt with a great deal of electronic equipment rated (and tested) to storage temperatures as low as -60C which contain electrolytic capacitors of several types. And I've stored batteries in the freezer for many years without harm. Freezing of electronic components is seldom a concern.

c_c


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## jasonck08 (Jan 22, 2014)

@ Therrin.

Did you charge any cells below freezing? Never charge Li-ion cells below freezing, it can destroy them.

Secondly, some cells maybe have about 50% of their full capacity at around -10C, and even less at lower temperatures. Some battery electronics/circuits may have a temperature sensor that shut off your phone for example.


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## Lampbeam (Jan 25, 2014)

I used to take pictures in the cold in Kansas. I put my camera in a bag afterwards when I brought it into the house to keep condensation from getting into it. I don't think this would hurt a flashlight but it might be something to consider with a cell phone. I think a cell phone should be kept in the pocket of an inner layer of clothing to help keep it warm.


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## Therrin (Jan 30, 2014)

Lampbeam said:


> I used to take pictures in the cold in Kansas. I put my camera in a bag afterwards when I brought it into the house to keep condensation from getting into it. I don't think this would hurt a flashlight but it might be something to consider with a cell phone. I think a cell phone should be kept in the pocket of an inner layer of clothing to help keep it warm.



The bag thing is so that the condensation forms INSIDE the bag, not on the camera. Most of the good cameras that people do this with are *somewhat* weather sealed, or have their charging ports up on the side of the body somewhere. If you were to try this with a phone, the phone would sit flat in the bottom of the bag, and condensation could dribble down the sides of the bag and ?possibly? make their way into a charge port? 

I'd be more inclined to bed it in some rice in a bag while doing this....

You keep your cell phone deep under your layers when moving about, yeah. While *using* it... hard to do the same 



jasonck08 said:


> @ Therrin.
> 
> Did you charge any cells below freezing? Never charge Li-ion cells below freezing, it can destroy them.
> 
> Secondly, some cells maybe have about 50% of their full capacity at around -10C, and even less at lower temperatures. Some battery electronics/circuits may have a temperature sensor that shut off your phone for example.



Well, I didn't charge any of my round LiXx cells out there, so that wasn't an issue. I just went to use that 26650 cell while I was out there, and it wouldn't work. (works now)
I *did* use my Limefuel to charge my phone several times, but that was usually in-doors w/heater or in my sleeping bag. After my phone froze I thawed it in my sleeping bag (erm... between my thighs actually ), before recharging it the next day.


Strangely enough, I have a new issue now.... 
I recently went on ANOTHER outdoor foray in Minnesota, out in the Fergus Falls area, and once again it was ~ -25*F while I was romping around outdoors. (I seem to have found a knack for finding the crappiest temps and then going outdoors to do things in them )

My SolarForce L2p w/ Thrunite XML dropin just up and died when I went to use it. Swapped 3 different 18650's in and out of it...no bueno.

Brought it home and rang out the switch, works fine...
Tested all the batteries, all fine...
Hooked up my external power supply and fed 4.2V to the dropin itself, no bueno...
Pulled the reflector off and lifted the insulator around the emitter; carefully, briefly touched the + and - pads and FLASH!!!!! ... blinded myself. :duh2: Score!

So I guess my driver died??? It had worked fine the day before, then temps dropped again and I went to use it that morning and just didn't work. I've had that dropin for about 3 years and never had any trouble with it at all. Windchill was somewhere in the -50*F's again that morning. 
The cold is the ONLY thing I can attribute to that driver just up and dying on me. Unless, it just chose that moment to wear out?? 

I'm working on disassembling the driver pillar to play Mortuary Tech on it, but I gotta go get some wicking braid tomorrow to get the pillar partition board out; then maybe I can figure out what failed.


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## HKJ (Jan 30, 2014)

Therrin said:


> The bag thing is so that the condensation forms INSIDE the bag, not on the camera.



Not inside the bag, but on the outside of the bag.

A explanation: Warm air usual contains more water than cold air. When the warm air hits something cold it will be cooled down and the water is left on the cold stuff.
By leaving the camera in a closed bag, you keep the warm air away while the camera is warmed up.

I have left out anything about humidity (%RH) and dewpoint from the above, but that is what leads to condensation.


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## Therrin (Jan 30, 2014)

Now I'm just all kinds of confused. My g/f does this with her Canon D5 MkII and winds up with condensation inside the bag. I thought that was always what happened.... *scratches head* 

Have you ever heard of cold temps killing driver boards or dropins??


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## HKJ (Jan 30, 2014)

Therrin said:


> Now I'm just all kinds of confused. My g/f does this with her Canon D5 MkII and winds up with condensation inside the bag. I thought that was always what happened.... *scratches head*



Sounds like see is doing it the wrong way. The bag and the air in the bag must be cold when the camera is put in and the bag sealed.
Then the bag must not be opened before the camera is warm.



Therrin said:


> Have you ever heard of cold temps killing driver boards or dropins??



No, electronic usual works fine in cold temperatures (Except LCD displays), but condensation can kill it.


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## Therrin (Jan 30, 2014)

Thanks, I'll make sure she does it that way for sure next time!

I hadn't considered condensation inside the light, perhaps that was it. I'll try to figure out what fried when I get it apart and post back.


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## HKJ (Jan 30, 2014)

Therrin said:


> I hadn't considered condensation inside the light, perhaps that was it. I'll try to figure out what fried when I get it apart and post back.




I forgot one thing: Large temperature changes, it can crack solder joints or other stuff due to differences in thermal expansion


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## markr6 (Jan 30, 2014)

Therrin said:


> So I guess my driver died??? It had worked fine the day before, then temps dropped again and I went to use it that morning and just didn't work. I've had that dropin for about 3 years and never had any trouble with it at all. Windchill was somewhere in the -50*F's again that morning.
> The cold is the ONLY thing I can attribute to that driver just up and dying on me. Unless, it just chose that moment to wear out??



I've been noticing in the cold that the burst mode on my two PD32UEs isn't any brighter than the mode below. I alwasy figured it was the batteries. So I took some 18650s from indoors and put them in a cold light. Still no go! So I guess it's something to do with the driver or LED itself. Once it warms up everything is OK.


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## Therrin (Jan 30, 2014)

HKJ said:


> I forgot one thing: Large temperature changes, it can crack solder joints or other stuff due to differences in thermal expansion



This thing looks like crap inside. I got tired of waiting for the RadioShack to open to get some desoldering braid, so I tooled at it with some scrunched-flat stranded 28awg; then I got impatient and grabbed my Dremel box and browsed through a plethora of bits till I found one that looked good and attacked it. Took about 4 seconds after that. 

It's two double stacked boards with SMD's. One of the solder joints that stacks the two boards looks really crummy.






One solder riser is measuring 0.6ohms and the other one is reading 1Mohms. :huh: That can't be good.

I think I'm going to get a replacement driver board off Fasttech and rebuild this thing for a little higher output. Fun little project, either way.

Didn't mean to derail this thread. I THINK this all kind of applies, but I'll cease and desist now.


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## Max Ohms (Jan 31, 2014)

I took 4 CGR18650CG's that I have been abusing.........uh.... testing outside one morning a few days ago and put them on some ice in a chair for about 15 minutes (temp was about 30F.......I'm in Texas!!).

I immediately put them behind T6's for a run test, and all 4 ran on high for 2h, 15-20m (from 4.2v to 3.2V +,-).


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## HarryN (Feb 3, 2014)

I built an LED "boost driver" a few years ago, mostly following a chip supplier's design. One of the very interesting things I learned is that the properties of both active and passive components change pretty dramatically over the temperature range you are discussing.

For example, most controller chips are not rated at even 0 F, much less lower. For this to be "certain", you have to buy ones which are specially rated for that temperature range. (sometimes called automotive temperature range, mil spec, or COTS) depending on (-40 F or -55 C)

The properties of simple passives such as resistors and capacitors (which control the levels and other aspects) change dramatically over the indicated temperature range, unless you pay for very high quality ones. As an example, a solid state capacitor which is rated to work with similar properties down to (-40 C) might cost $ 7 each vs. $ 0.20 / each for ones rated to operate down to maybe freezing.

If the LED driver in your flashlight cost less than $ 100, it is frankly unlikely to have been designed, or contain components, that are designed to work at (-40 F).

The exception might be if it is a simple resistor limited light, which is one place this approach can really shine.

The same thing is true for your cell phone, its design range is most likely 32 F to perhaps 100 F, not (-40 F).

Of course, the cold affects the battery / cell performance as well.


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## HKJ (Feb 3, 2014)

Normal components are usual not rated for lower temperature than 0C, but they do work at much lower temperature.
Resistors do not change much. Some capacitors do change significantly with temperature.


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## Pöbel (Feb 3, 2014)

yeah, super late follow up but I would still like to elaborate

not every fluid increases it's volume when frozen (quite the opposite actually). We might think that as the most common fluid in our lives has that anomaly but that is misleading.


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## HarryN (Feb 3, 2014)

HKJ said:


> Normal components are usual not rated for lower temperature than 0C, but they do work at much lower temperature.
> Resistors do not change much. Some capacitors do change significantly with temperature.



Do you consider a 50 percent change significant? That is how much a conventional resistor or capacitor properties can readily shift from room temperature to -40 C. For DC it might not be much, but for drivers running at 1 kHz or 1 MHz it sure does.


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## moldyoldy (Feb 3, 2014)

The comments about temp ranges of the components are needed inasmuch as most consumer electronics are certainly not qualified for sub-zero F operation. COTS (Commercial Off The Shelf) components may well be whatever did not qualify for lower temps such as Automotive or Mil-Spec. IOW, the left-overs from a production run. Good luck!

However there is another factor which has not been mentioned: The in-rush current at startup. That can be devastating to a circuit and especially capacitors below their qualified operating temp. Flashlights use two types of components more susceptible to cold temps: capacitors and inductors, and by inference, the solid state devices driving the inductors, usually DC-DC converters. The better electronics are designed with a 'soft turn-on' to avoid the in-rush problem. However that takes more electronics and a lot of environmental chamber testing - always expensive. 

As an example, think back to the early compact fluorescent bulbs with electronic ballasts. They failed rather quickly when turned on in sub-zero F temps. Yet if you could turn them on daily - only once - before the temp plunged, they would run all night long w/o problems for weeks. Specially designed CFLs were available - for a price - to operate in outside temps. The problem was not the high temps, rather the low temps. They were designed with special soft-start circuitry. Now most consumer CFLs will operate in outside fixtures and not fail too often.


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## HKJ (Feb 3, 2014)

HarryN said:


> Do you consider a 50 percent change significant? That is how much a conventional resistor or capacitor properties can readily shift from room temperature to -40 C. For DC it might not be much, but for drivers running at 1 kHz or 1 MHz it sure does.



A ceramic capacitor can have very wide tolerances, it can even change value with voltage. There is a reason that one of the standard tolerances for capacitors is -20% to +80%
Resistors will only change a few percent, many of them are rated to -55C or -60C 

There is nothing magical about going below 0C, but parts are usual rated at 25C and down to -40C is a 65C temperature change, this will change component values, but seldom enough to make electronic stop working.


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## Curious_character (Feb 4, 2014)

Designing a circuit so it'll operate properly over a specified temperature range is one of the challenges faced constantly by design engineers, and it's one of the things that separates their designs from hobbyists'. Electronic circuits are commonly designed to work properly at temperatures several tens of degrees below zero C. But it doesn't come without some compromises, or without a fair amount of knowledge and experience.

About ceramic capacitors -- they're made with many types of ceramic with very different properties. Ones designed primarily for bypassing are physically small due to the high dielectric constant of the ceramic used. Type Z5U is typical. These have the very poor temperature coefficient, and change with applied voltage as well as HKJ says. And they're microphonic, piezoelectric, and hygroscopic. But they are small, so you get low reactance and a high self-resonant frequency. Type X7R is much better for general purpose, since they're much more stable at the cost of being larger. And C0G (NPO) capacitors are hard to beat for stability by any other kind of capacitor.

c_c


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## Therrin (Feb 4, 2014)

I'm not on your folk's level here; but how would you design soldered junctions to not be (as) affected by drastic temperature changes? 
My light went from a warm hotel room to ~ -25*F in a matter of minutes, and I hadn't even considered what that could do to my electrical components. 

Those temps are not uncommon in those parts of the country, but I doubt people purchase electronic products that are rated any differently for normal use. 

The (-40*) stuff was a bit extreme even in those areas, and at those temps MOST people are inside their heated houses, not mucking about out-of-doors like we were... so perhaps such things wouldn't be noticed.

But even then, such temps aren't abnormal in places like Alaska and Canada and other parts of the world. 

I guess if it's a military or other high-end or scientific application, those things are taken into effect. Otherwise on the consumer level whenever something doesn't work right or dies outright, the user just goes "awww damn" and goes and buys another one.


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## moldyoldy (Feb 4, 2014)

Therrin said:


> I'm not on your folk's level here; but how would you design soldered junctions to not be (as) affected by drastic temperature changes?
> My light went from a warm hotel room to ~ -25*F in a matter of minutes, and I hadn't even considered what that could do to my electrical components.
> 
> Those temps are not uncommon in those parts of the country, but I doubt people purchase electronic products that are rated any differently for normal use.
> ...



Solder comes in many types. non-lead-based solder has mostly taken over. There are some special silver solders, etc. such as for space-qualified electronics which may be required to meet a 20 year deep-space lifetime requirement. 

ie: Voyager 1 and 2 were launched about 1977 and operate on an Intel 8008 or 8080 (intro'd in 1974). Voyager 1 was in NASA news that it has entered interstellar space - beyond the Sun's Termination Shock and probably now beyond the Heliopause - meaning "out there", beyond this Sun's solar system.

note: a 20 year deep space requirement is why many such electronics do NOT employ the latest high-density ICs. Molecular migration will cause those devices to destruct well before 20 years have elapsed. As always, testing is long and strenuous on the electronics as well as the designers since test results might only be known 6 months later. 

If the PCB is large enough, a tech puts on a hood or a zoot-suit with positive pressure airflow, goes in to a sealed spray booth with a strong exhaust system, and sprays the boards with a non-conductive epoxy-type coating which seals the PCB, components and solder joints. That is commonly used for military electronics, most automotive electronics, and maybe the better consumer electronics. 

Otherwise if the electronics module is small enough, the entire assembly is potted in an epoxy resin. That reduces the susceptibility of the design to sudden temp changes. The correct epoxy will also facilitate heat dissipation. I recall someone reporting that Zebralight is potting some of their electronics.


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## moldyoldy (Feb 4, 2014)

Apologies to the OP for going so far off topic. 

Back to the original question: It has been my experience that the size of the Li-Ion cell makes quite a difference when taking a light out in the cold, meaning well below freezing if not below 0 deg F. The larger the cell, the longer it can survive with some sort of decent runtime. that also depends on how many other cells are positioned next to each other. ie: 10440 or 14500s do not last long because of low thermal mass. The 18650s have not failed me on hour walks in temps below -18C or 0F. On single 18650 lights, the high is not so high any more, but still brighter than the next level down. I do not have a 26650 light, but am watching the Olight R40.

As always, let the Li-Ion cells warm up before charging.


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## HarryN (Feb 5, 2014)

I guess I was thinking more about lights that will work after "soaking" at low temperatures overnight than ones that just are moved from a warm house to outdoors.

It is true that professional electrical engineers can design circuits to compensate for wide temperature ranges. I know of two methods - compensation balancing and buying higher quality parts. I really doubt that either are actually being done in a flashlight that sells for under $ 200 though, but maybe I am wrong.


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## rwfishman (Nov 8, 2014)

*Rechargeable Li-ion batteries*

Thread Merge

I'm new to this site (and to good flashlights) and tried to find an uncomplicated answer to this question online with no success. Hopefully someone can help me here.

I just purchased a Nitecore SRT7 flashlight and 3 of their rechargeable Li-ion batteries. From my experience, regular lithium ion batteries work well in very cold (under 32 degree F) temperatures. What are the temperature ranges of the rechargeable lithium ion batteries? Specifically the Nitecore NL189 3400mah Li-ion rechargable battery? Since it can get below 0 degrees fahrenheit in New England, can I store my flashlight in my car during a New England winter and have the flashlight work dependably? Is there anything else I need to know about proper storage?
Thanks in advance for your help!


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## ven (Nov 9, 2014)

*Re: Rechargeable Li-ion batteries*

:welcome:Lithium cells do loose charge and performance at a quicker rate the colder it is subjected to. Have a little search as lots of info on here regarding temps and li-ions
http://www.candlepowerforums.com/vb...um-Ion-below-freezing-temperature-performance

My advice would be to keep the light in something to insulate it in the car,something to keep the cold off basically . Also long term storage is not ideal at 4.2v so maybe a happy medium of 4.1v (90% charge) although many have issue free trouble at 100% charge . Just check cell/s regular (ie every 2 or 3 months) if its for emergency use:thumbsup:


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## NoNotAgain (Nov 9, 2014)

*Re: Rechargeable Li-ion batteries*

Since the SRT7 comes thru with a CR123 adapter, I'd look at getting one of Surefire's battery storage containers, SC-1 or SC-2 and keep some primary lithium batteries with the light. 

I use a film insulated cooler bag to store my light in. Keeps it from cooking in the summer and freezing in the winter.


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## RI Chevy (Nov 9, 2014)

*Default Re: Lithium Ion below freezing temperature performance*

Welcome to the forum! :welcome:

Check out http://www.batteryuniversity.com/ for a lot of useful information and safety tips using Li Ion batteries.


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## Zoroff (Feb 19, 2017)

*Re: Default Re: Lithium Ion below freezing temperature performance*

I did a simple test at home with an Armytek Wizard high CRI in the freezer with
two different ICR batteries just to see how the higher performance is affected by
the high current capacity. The 30A did better at delivering 
One good thing from the e-cigarette/vaping community is that high drain batteries
are becoming common, at good prices too. I bought mine at nkon.nl.


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## Phlogiston (Feb 24, 2017)

*Re: Default Re: Lithium Ion below freezing temperature performance*

Here's a link to a post where I was suggesting how to assess the likely performance of different cells (mostly Li-Ion 18650s) at very low temperatures.


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## Gauss163 (Feb 25, 2017)

*Re: Default Re: Lithium Ion below freezing temperature performance*

You can also find discussion of low-temperature Li-ion performance in threads on Li-ion powered hand and foot warmers.


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