With my Kia hybrid parked for the winter I have been starting it every few weeks but today I went out and it was dead. I did the 12 volt reset thing and it started and I was wondering if I should put a battery tender on the battery. The temperature has been below zero at night and on occasion during the day. I didn't know ifa battery tender would hurt something in the Kia's electrical system or not. I would appreciate any thoughts on the subject.