Your account sounds different from what GP describes (ie. descending from full charge in a few minutes, without any activity). I live an a region that regularl

Your account sounds different from what GP describes (ie. descending from full charge in a few minutes, without any activity). I live an a region that regularly stays below 0F for months on end and have never seen or experienced such extremely accelerated loss of charge. However, I have certainly seen phones lose charge more quickly once they get below 50% or so--I never correlated that with the cold, but maybe there is a connection.