Originally Posted by greatlakes
What part of the country you in? My concern was being on the Michigan Ohio border I was afraid the batteries would freeze if we had a few days of below 0 temps. We haven't but my garage is a little bit warmer all the same.
I was in PA. Rarely below zero.
But, grew up in MN. My boat or car battery never froze. I always charged em up before winter. If it is a weak battery it may lose charge. I replace mine before that by hydrometer testing.
I understand that If the battery is dead, the acid turns more to the state of water which would start freezing at 32 degrees F.
On the web:
Battery freeze points depend on state of charge or discharge. A brand new fully charged battery will not freeze unless the outside temperature is - 77 F. A battery that's only charged to 75% will freeze when the outside temperature reaches - 35 F. A 50% charged battery will freeze @ -10 F. A 25% charged battery will freeze @ + 5 F