I ride year-round and found with my first set of battery gloves (most are lithium nowadays), when I REALLY needed them (sub 20* temps) they didn't work/shut off. Called Gerbing and they said, "Yeah they're not meant to be used that low". WTF? You can also try adjusting your Barkbuster a little. I leave mine a little loose so I can adjust on the fly. When my fingers start getting numb, I move them down a bit 'cause I find that it's my fingers sticking below the handlebar that gets the coldest.