I just came back from a holiday, and booted up my MacBook, which had been shut down (or so I thought at least). When I started the computer, it booted as if from safe sleep (with blurred screen and progress bar) and then shut down immediately. When I tried to start it again, it booted normally, but it didn't recognize the battery (shows only an 'X' on battery meter). The charger led glows green and none of the lights on the battery are on, neither when the battery is connected nor when the charge-checking button is pressed. I've tried removing the battery a few times and resetting the PMU, but neither worked. Any advice on this? Should I just contact a dealer for a new battery?