To clarify my last post. This is not a battery issue, but an operating issue. From Medtronics view, the device must be at least 32 degrees to properly operate. Bringing it from a very cold vehicle into a warm house does not count, the device itself is still to cold to operate. They go on to say that the device may be stored at -22, without batteries or electrodes. Reading between the legal lines, a lifepak below 32 degrees should not have a battery in it. If it does not work, the manufacture has no liability. That being said, I'd rather have a cold AED then no AED.