Winter is already well underway for the northern latitudes and that probably means storing your aircraft for the duration of the winter. If you have not already done so, you might want to take a look at the detailed winter primer that AVWeb has which also comes with detailed instructions for the Lycoming and Continental engines. In fact, the article has step-by-step instructions for how to deal with engines to get them ready for winter.
In addition, a pilot named Josh recently posted a question on the Ask a Flight Instructor site about keeping an aircraft battery alive for the winter:
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.
John D. Collins responded by saying he uses a product called Battery Minder that has a temperature probe and adjusts the voltage for temperature while Bob Watson pointed out that there are battery warming wraps for cars that go around the battery, but these are usually already out of stock by the time winter comes. However, Brian responded by saying that unlike car batteries today, most airplane batteries are acid filled and are not sealed batteries. That means:
If the highly flammable acid gases are not sealed in tight and if that blank shorts…well let’s just say it might be worth doing some investigation before putting one on an unsealed battery.
Finally, Sam Dawson wrote a lengthy response pointing out that battery manufacturers recommend the use of a battery for start in cold weather because it helps warm up the battery plus they have a blurb that states if the battery is not used for start, it may not be sufficiently charged for emergency operations. Sam ended his comment by saying pilots should read the operator manual for their battery and that it probably recommends the use of a battery minder below a certain temperature.