Replaced the battery and did everything suggested. Problem was fixed not by putting a new battery, nor inserting it while plugged and all that. I had to do a hot re-set on Windows losing many settings and programs. Problem solved? Yes, but today after a week working fine, it started doing the same thing!! Digging into this, I suspect a Windows update. When resetting windows, it tries to download updates, and one of these screws the battery issue, as reported by somebody on another forum. Asus techs have no idea why or what to do. A bummer.