And have some longevity in a desert climate....there's nothing you can do about your garaged car (a "five year" battery generally only lasts 2 out here), but I learned the hardway to NOT store my Makita batteries out there. I've made room in the sock drawer.
Heat kills batteries, fershur.
good call...most don't know that when a bettery dies in the winter, it's usually because it took a beating during the summer