Tested it with another usb cable, same problem
Strangely, the battery icons looks fully charged, and everything works as it should when plugged on usb or power cord, but if i unplug the power source [puff] it shuts down immediately
At first i thought it was some software problem that could be fixed with a firmware update, but now I am starting to believe that is indeed a battery problem. Any more suggestions?
Thanks for all the answers by the way.