I have a PA-24 Comanche and I live in Maine. The temps here are often near zero in the winter even if its sunny. I just put a new battery in the plane but the cold weather is too much and I am finding myself hot proping the airplane to start it, which doesn't excite me on an icy ramp. What could I do to keep my battery alive? I have a float charger on it, but it doesn't seem to be cutting it. The battery is in the tail of the plane.