One way to keep your water from freezing is to take it with you. This precludes keeping an extra supply of it in your vehicle, but at least you'll have what is in your water bottle or hydration bladder if things go bad.

If you want to keep an extra water supply in the car you could fill your own reused bottles only part way to allow for the ice expansion. Not as convenient but it could work, I wonder if anyone here has tried it with success?