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blythe · Nov 9, 2003, 03:35 PM

Would anyone happen to know if there are any adverse affects of exposing PB batteries to cold temperatures? I am going to have to leave my PB in my car for about 8-10 hours about three days a week this winter. Aside from condensation problems, is the battery life shortened when used after exposure to the cold? Will the permanent capacity of the battery also be decreased?

smitty825 · Nov 10, 2003, 01:41 PM

I personally would be more worried about the LCD displays. While I'm far from an expert in LCD technology, I do have some experience using them in the (very) cold weather as an astronomy.

It is my understanding that LCD stands for "Liquid Crystal Display". If temperatures get too cold, the liquid can freeze and expand, breaking the pixel. This happens on people's telescopes occasionally, and it usually ends up with someone having to buy a new hand controller!

However, I don't know if it is a problem with the powerbook, and exactly how cold your "cold temperatures" are :-)

Originally posted by blythe:
Would anyone happen to know if there are any adverse affects of exposing PB batteries to cold temperatures? I am going to have to leave my PB in my car for about 8-10 hours about three days a week this winter. Aside from condensation problems, is the battery life shortened when used after exposure to the cold? Will the permanent capacity of the battery also be decreased?

petehammer · Nov 10, 2003, 01:51 PM

Originally posted by blythe:
Would anyone happen to know if there are any adverse affects of exposing PB batteries to cold temperatures? I am going to have to leave my PB in my car for about 8-10 hours about three days a week this winter. Aside from condensation problems, is the battery life shortened when used after exposure to the cold? Will the permanent capacity of the battery also be decreased?

From my experience with camcorder batteries: not a good idea. I'm sure google can answer your "long-term" effects questions, but when I exposed camcorder to sub 30 degree temperature (not that cold) battery life was at least halved. The only solution we could find was wrapping the camcorder in a fleece blanket to increase the heat.

My advice? Put the PBs in cases, then wrap the cases with a blanket. You want to keep them out of the freezing range and preferably above 40 degrees.

blythe · Nov 10, 2003, 10:42 PM

Thanks for the help. I found a pretty useful link that answered my question. It seems that long term capacity won't be affected by the cold, whereas the immediate discharge of current would be affected.

http://chemistry.about.com/library/weekly/blbattery.htm

Now the frozen LCD problem is worrying me. I'm thinking that the tempterature range will be from 10 - 32 degrees F.

dreamBweaver · Nov 11, 2003, 01:39 PM

I go to school in Rochester, NY (lake effect snow) so your post is of interest to me. I have read the iPod wasn't meant to be exposed to temps below 32 F...but that's ok as long as you realize the battery life that time will be reduced. I am not sure about the PB. btw I have a PB12" and always keep it in a carrying case when i'm not indoors.

xylon · Nov 11, 2003, 01:47 PM

Hmm, this makes sense. My mother read somewhere that to extend the shelf life of new batteries, you keep them cold. So we used to have a ton of batteries chilling in our refridgerator. Sure enough, it worked. Batteries that came out of the refridgerator and put into use after their "best if used before" date did better than their non-chilled counterparts (we had a camping trip and loaded all the flashlights/radios). So, I guess these results informally support the idea that chilled battery output is reduced.

petehammer · Nov 11, 2003, 01:50 PM

Originally posted by blythe:
Thanks for the help. I found a pretty useful link that answered my question. It seems that long term capacity won't be affected by the cold, whereas the immediate discharge of current would be affected.

http://chemistry.about.com/library/weekly/blbattery.htm

Now the frozen LCD problem is worrying me. I'm thinking that the tempterature range will be from 10 - 32 degrees F.

Just don't try this trick:

I'm in Minnesota shooting a movie for school during the winter at night. It's at least 20 below zero. Vidcam is filming and then suddenly, for lack of a better term, seizes up. The motor stops rolling, the LCD flickers, and the zoom toggle stops working. The autofocus starts going a little journey of focus/don't focus... and eventually (after about 20 seconds) shuts off completely.

In horror, I rush the thing inside. Luckily it all worked fine the next day. But at the time... dear lord, a 3-ccd vidcam that wasn't mine. D'oh!

I had wrapped the thing in a blanker and had a special lens covering the normal lens. Still not enough heat though. And not something I'll be trying again soon.