3 batteries are very warm in the bag 2 @ 85.7 degrees and 1. @ 86.1 F GB degrees. The battery in the drone that I just brought in from outdoors reads 76.4° F. The outdoor temp. Is 30°F. As I was going to put the drone back in the bag I felt the warmth on my hand as it escaped the bag and I knew something was not right. The bag was not sitting next the a heater or radiator and such.. The only warm part of the bag was is the compartment where the batteries were stored. Any clues to this phenomenon?