A friend of mine just upgraded to the iPhone 6 from the Apple Store. He took the device home only to find out the battery was completely dead out of the box. On top of that, the iPhone had iOS 8.1 on it! Obviously the batter has been dead for quite some time. Is there a chance for any adverse effects on the battery since it was probably sitting dead for quite some time? Or will it be fine once he charges it up and starts using it?