I haven't heard of that. We were on a 3 week cruise from Rio to Valparaiso. My brother was the photographer of our group and he took hundreds of pictures. We were 4 days in Antarctica. He did take a backup battery but there was no problem and as I said he took hundreds of pictures over the course of the cruise. I think it may be a little different if you are on a land expedition being exposed to the temperatures for a much longer period of time.

I worried about this before our trip to Antarctica last year, but it turned out our camera batteries didn't suffer at all. We used a Canon 1D Mark III and a Canon 40D with a battery grip, and both cameras' batteries performed exactly like they always do in warmer weather. My Mark III was getting 2500-3000 shots per battery, and the 40D with two batteries was doing about 2000-2500 shots. This was in conditions where the cameras were outside in the cold for extended periods of up to 4 hours on shore landings.
The official literature from Canon indicates that at 32 degrees you should expect a hit of about 30% on battery life, but that definitely was not the case for us. In fact, our Canon cameras performed flawlessly in every respect throughout the trip, through temperature and humidity changes, light rain, snow, sea spray, and getting knocked around in the zodiacs!
Hope this information helps you.
Chris

As an addendum to the above post, my wife and I took over 26,000 pictures on our trip, so we had lots of opportunities to study the battery life of our two cameras.

Chris

I'm currently packing for Antarctica (yay!!!), and I'm bringing plenty of those hand warmer packets to stick in my internal pockets along with my camera batteries.

thanks guys for your ideas, I feel better now!
I'll carry at least a set of 2 batteries, hoping they will last enough for each landing.
I'm preparing also psychologically for the big cold!
happy travels
Nik

Nikosk - We were there in January and although it was cold it wasn't that bad temperature wise - it was the wind that got to you. I would be sure to pack something that is extremely wind resistant. We just wore regular jackets underneath. I would recommend a jacket that has a hood that you can tie tightly.

On my last trip, I had 3 batteires and I have never used more than two on any given day. (I have a Canon 50D) Just have to remeber to recharge the abttery every night before dinner

Most days, I used only one. Mind you, I have turned off review so the batteries will last longer! I don't travel with my battery grip any more as it was too much to carry. I have also cut back on the lenes too. I only bring my cheater lens (18-200) and left my tele and wide at home. DW gets cranky when I carry too much gear