Default [Q] How bad is it to leave my phone outside in -15C cold weather?

I have a bunch of old Android devices, and I was looking for ways to use them. My mother wanted a security camera for her front door, so she could see who was ringing the doorbell, and I immediately thought of my old Motorola Atrix MB860. I rigged up a little holster for it, and for the past 2 months it has been quietly chugging along as a semi-reliable security camera using the free IP Camera app (I say semi-reliable, because every 5-7 days or so, the phone seems to have rebooted itself for some reason, and one needs to go out there and restart the app).

Right now we're having the coldest night we've had all winter at -15c, and if you've ever lived in Toronto, you know that isn't very cold. According to my remote monitoring system, the Atrix's current battery temperature is -1c. The phone is plugged in, and I don't really care if the battery stops working, but I am curious;

Is leaving it out in the cold very likely to permanently destroy the phone? Or even just the battery? I have heard conflicting things about li-polys in low temperatures; some say that they work their best at low temperatures, running more efficiently, and there is no risk of damage because li-poly does not change its crystalline structure very much under temperature fluctuations. Others say they can be up to 40% less efficient in below-freezing temperatures. A few others say it will likely destroy the battery.

Again, I really don't care about the battery, but if there is obvious evidence/sources that say the phone itself will likely die, I would like to know so I can dismantle it.

DISCLAIMER: My post may be a repeat of a previously asked question. Please dont dismiss my question and tell me to "use the search". Sure, I may be able to find the answer by searching for it, digging thru dozens of locked threads, digging through pages of posts to find the one single answer I need...

But I have faith that there will be one decent human who is willing to save me the time of searching, and answer my repeat question.

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