Mine was starting to act strangely. I have it on the wireless charger and it would take forever to charge. So I plugged it into the wall charger and it charged a little faster but still not as fast as I remember it charging before. So I took it out and replaced it with a new backup. After ten minutes on the wall charger, it was over 40% charged. When I looked at the old battery, I noticed it was bulged out top and bottom at lease 2 milimeters. That bulge didn't look good. I wonder if wireless charging is to blame or is just wore out. Any thoughts?