I believe Trojan is adding the cover your rearend with deny deny deny warranty claim options.
With the price of lfp cells now and some homework a nice size battery bank can bebuilt at a very reasonable price equal to or less than lead batteries. Even this concern of cold temps is something that can easily be figured into the build/ placement of batteries and if that can't be overcome than lfp isn't a good fit for your wants and stay with tried and true batteries already on the market.
I thought I had colder temp readings but I don't. Last Nov I had outside temps of 7f with compartment temps of low 40s and my cells dropped to 32f which stopped charging but had no problem still using them. I took my small heater I have and throw it in the compartment within 20 minutes all cells above 35f. I think having the ability to monitor cell temps is important because going off ambient temps is just that ambient temp.
Here was just mild temps of 29f in the morning.
