Real World Test - COLD WEATHER

Real World Review - COLD WEATHER

This week has seen the weather go from the high 60's/low70's down to the 20-30 degree range. However the wife and I have continued to do our evening walks (albeit with a LOT more warm clothes on now). Our walks cover 2.5 miles and the terrain covers a well-lit neighborhood, an unlit bike trail, and a badly lit neighborhood. We usually take between 35-45 minutes to complete the walks and the flashlights were exposed to the elements for the duration (no warming up in the pockets, etc).

I have covered the general charistics of these lights on other "real world" reviews so this time I'm going to limit myself to cold weather related comments.

Gerber LX 3.0 - Still easy to handle/use with bulky gloves on. I use 2300mAh NiMH batts in it. The NiMH's suffer BADLY from cold. Within 5 minutes of starting the walk I would estimate the light had dimmed down about 10-15% from it's usual brightness. The light stayed at roughly the same level through the rest of the walk but the performance change was obvious.

Night-Ops Gladius - Still easy to handle/use with bulky gloves on. No surprise here as it was designed with that in mind. Lithium cells seemed completely unaffected by the temperatures. Flashlight performance seemed unaffected.

Inova T4 - Still easy to handle/use with bulky gloves on. The large cut-out for the switch and the large switch were of benefit for use in these conditions. The Li-ION power pack seemed completely unaffected by the temperatures. Flashlight performance seemed unaffected.

Surefire 6P - I found the smaller size of the 6P to be a little more difficult to use with bulky gloves. Not too bad though. Lithium cells seemed completely unaffected by the temperatures. Flashlight performance seemed unaffected.

As I cold-weather test more lights I'll post the notes.

Do you have any AA NiCd cells? I'd be interested in what you think of their performance in the cold.

I live in Maryland and used gloves today for the first time this season. I'm going to have to enlarge the hold of my flashlight's lanyard so that it fits over my gloved hand. In fact, I'll have to got to an adjustable lanyard so I can use it with or without gloves.

When wearing gloves, I think that a bezel-mounted switch like the Stinger's would come in handy.

Hey Paul in Maryland,
Yeah I forgot to mention the lanyards as well, thanks for the reminder. The nice thing about most of my lights is that I have adjustable lanyards attached to them (a-la-surefire's lanyards).

BackBlast - I do have some AA NiCd cells (they power my radio scanner) I'll try and remember to pull them out and try them on tonight's walk but past experience (with my MagCharger) is that NiCads ARE affected but not usually as badly as the NiMH seemd to be. I was really surprised at how great the impact was on the NiMH cells!

From my person experience and testing I would like to throw in a few comments as well:

Lithium primary cells do very well in the cold. It isn't until about -20F that you can visually tell that performance is suffering.

The rubber boots on most Surefire tailcaps, maglites, Streamlight lights and others really start becoming stiff and difficult to use in the -20F to -40F range. It becomes more difficult with gloves on to boot.

In the -40F to -60F range you really start getting lithium cells hammered. This is where plastic bodies, or lights with a plastic sleeve (Gladius) really start coming more useful as they insulate the cells and help keep the cell temperature up.

A surefire 6P at -80F to -110F becomes difficult to use. The tailcap becomes difficult to turn if there is any lubricant, and the rubber stich on the boot becomes very stiff. Running Lithium 123a cells, I have not run into a light that would not come on at this temperature. Incan's are generally yellow and weak, but still produce light. LED's typically act like the battery is low.

The magnetic switch on the Gladius works extraordinarly well in the cold.

My general conclusion is that for Lithium 123a powered lights, cold is a non issue for functioning until you get to the -20F to -40F range. At these temperatures there is usually snow and dry air, so less light is more effective.

UVvis get's my "Flashaholic of the day" award...-40 to -60 or worse... and he's still testing flashlights!
:rock:

Heck, by -10 I've packed it up and gone home

Um, UVvis, where exactly were you whilst you were testing flashlights at those temperatures? :wow:

the Gerber is a direct or resistor driven led i think

In a nichia datasheet you can find information that @ cold ambiente temp. the Vf @same current level increase. Lumileds iám sure act same way.

This and the decrease of the voltage of your rechargable are the reasons for that behaviour.

Thx a lot for sharing your experiance with us!

I believe that you are correct that the Gerber is a resistor driven light. One of the things I plan to do is test the voltage on fresh off the charger NiMH batts, and leave them on an outside window sill while I do my evening walk and then test them again after they've been cold for a while. I'll post the results.

I should probably do the same with some NiCad and Lithiums just for comparisons sake.

My residence is in the US, but for a while I'm in the super deep south, in the Antarctic.

I play with the lights when I'm here in colder/darker months, and in the cold labs.

UVvis said:

My residence is in the US, but for a while I'm in the super deep south, in the Antarctic.

I play with the lights when I'm here in colder/darker months, and in the cold labs.

Click to expand...

Very cool! (pun intended, sorry) But aren't you headed into "summer" down there, with the midnight sun? The flashaholic in me shudders to think...

I have not done a real world test, it was more like a real freezer test. I have put my Aurora 2AA with 2 alkaline batteries inside a freezer at -35 degrees Celcius. After hours there was ice all over the flashlight, but it still worked and it was brighter than ever before

Amadeus93 said:

Very cool! (pun intended, sorry) But aren't you headed into "summer" down there, with the midnight sun? The flashaholic in me shudders to think...

Click to expand...

Yes, 24/7 daylight till March. 2am is normally just a little darker than 2pm.

@erasmus

-35 degree WOW
but that´s also not untypical! take a look in the lumiled datasheets http://www.lumileds.com/pdfs/DS45.PDF Page 10
by the way it´s a good sign for the regulation

UVvis said:

My residence is in the US, but for a while I'm in the super deep south, in the Antarctic.

I play with the lights when I'm here in colder/darker months, and in the cold labs.

Click to expand...

Or you coulda just come up North and hung out with us Canucks for a bit, we have good beer! :rock:

Firebladz.

Update on the cold weather tests (though I feel a bit silly after UVvis)

I took out the following light/battery combinations...

Inova T4 (rechargable Li-ION)
Gerber LX 3.0 (NiMH rechargables)
CMG Reactor III (NiCad rechargables)
Princeton Tec Impact XL (Standard Alkalines)
Night-Ops Gladius (CR123A Lithiums)

It wasn't quite as cold as the first test (about 36 degrees) but I still got similar results.

The T4 and Gladius, once again, completely ignored the cold.

The Impact XL dimmed a slight bit but I only really noticed when I metered it. The same was pretty much true for the CMG Reactor III.

Once again the NiMH batts in the Gerber dropped abruptly about 10-15% but then stayed there for the duration.

This actually is consistent with my findings for using NiMH batts in my cameras when it is cold. The camera would quickly start giving me low batt warnings, but continue to operate for a long time thereafter. It does seem that something in the NiMH chemistry is heavily influenced by the cold. It doesn't seem like it affects the capacity too much but does seem to slow down the rate at which the battery can deliver power.

I for one say "Thank You" for the different data points, both moderate cool temps from 'zespectre' and the "OMG-ccccooooollllddddddddd" info from 'UVvis'.