Someone told me cold weather isn't good for cell phone battery. Unfortunately, my entire area lost power due to the snow storms this past weekend, and may not be back for some time. I can charge the phone at work, but when I'm home it's very cold and my cell phone, thus, gets cold. Am I doing any permanent damage? I left it in airplane mode over night and it went from 87% to 85% so I assume it's OK but I had left it by a window not thinking.