firefightersink wrote:
Thank you all, I feel kind of stupid. I am used to sealed gel batteries and when I switched, I didn't realize they contained water. I froze them. New point on the checklist to remove batteries. Also found water in my battery cases. Added to the mayhem. Thanks again for the info and replies. Always valued.
It is the discharged state that allowed them to freeze, not just because they have water. A fully charged lead-acid battery will not freeze under typical winter temperatures.
http://www.progressivedyn.com/battery_basics.htmlCan my batteries freeze?
If your battery is partially discharged, the electrolyte in a lead acid battery may freeze. At a 40% state of charge, electrolyte will freeze if the temperature drops to approximately -16 degrees F. When a battery is fully charged the electrolyte will not freeze until the temperature drops to approximately -92 degrees F.
Although maybe the battery cases filled with rain water over the camping season and THAT water froze during winter and crushed the batteries within them? My old 12V cases didn't have any way to drain and I did find one filled to the brim with water once. I drilled drain holes in the bottoms of my 6V battery cases so that wouldn't happen again.