MacBook stuck at boot time

Over the weekend my MacBook starting acting up; it remained stuck at boot-time, before graying up the display.

I've managed to start it by removing the battery and booting with the battery removed - what I've noticed that later on, after adding the battery, the battery menu listed over 1000 hours of usage time remaining.

So I'm not what sure what the problem is, once I've got the MacBook running and disconnected the charger to drain some power out of the battery, it boots without problems.