How do regular rechargeable batteries do in cold temperatures?

How would regular 1.2V rechargeable batteries do in extreme cold temperatures like -40, even if they were receiving a charge in that temperature? They would be kept in an air tight container.

Thanks in advance.

I don't have anything to back this up as proff, but I know that batteries don't do well in cold. Just like a car battery has a normal and cold cranking amp, I'd say smaller batts work along the same lines. As for charging in the cold I'm sure it is effected in a simlular way.
.  +1. Chemical reactions slow down at lower temperatures. Output decreases and recharging time increases.
.  Not sure where "regular 1.2V rechargeable batteries" freeze, but it's probably above -40.