I pulled the long a complete charging cycle, at the end of the battery was full - but it is annoying uncommonly (you can not permanently look at the display so that the connection is still there).
Those who mind do not mind, is with the battery compartment secure well served (in this price) - but I send it back.
Allegedly come error and demolition only in iOS 7 (I can not judge, I could not test before the update).