A fully charged battery in good condition will not be harmed by
extreme cold. I leave my batteries on the tender all year round and
never remove them from the trailer. I realize we don't have the cold
in KY that you do but my answer stands.
I'm allergic to work in general and heavy lifting in particular.
I see no good reason to carry those heavy suckers if I don't have to!
Do check water every few months. My battery fluids are still OK after a
year on the tender and that includes several camping trips.
Randy, if you don't have power at the trailer you can bring the
battery into your shed or basement.
A battery on a tender in your basement will outgas very little.
Also don't fall for the old wives tale about batteries being damaged
by sitting on concrete. It's not true anymore. Today's plastic case
batteries don't care if you sit them on the concrete.
My 2 plain old 12v marine RV deep cycle/crank batteries worked
just fine when we dry camped 5 days this summer.
They are 4 years old.
I'm still on my original truck battery and it's going on 9 years old.
Battery tenders really help prolong the life of batteries in vehicles,
RVs, boats, etc that only get occasional use.
You can find battery tender Jr online in the $25 range.