Well that absolutely sucks for most of North America.
Interesting. -25C is only -13F. In my bit of the world, thats about the average winter temp.... I wonder if sticking to AGM, fabing up some heated blankets, and using a more old school method is going to be the way to go for those of us in colder climates. Obviously there is a solution seeing as how many rigs are on the north slope....This sensor will allow charging of lead acid batteries down to -25degrees C. PDF attached.