MacBook: won't startup unless plugged in

My MacBook sounds rather grimly like all of these. I wonder about those MagSafe adapters ...

Here's how it went:

1. Went to use it and it was shutdown! Surprise.
2. Pressed power, it started to boot, I heard the optical disk spin up, then nothing. This is the same behavior one sees when a battery is completely depleted -- the Mac starts on its internal battery, recognizes there's insufficient power to continue, and shuts itself down.
3. Attached adapter, glowed green, booted.

I went through a few of these cycles. Sometimes it would start unplugged if I pushed the power button a few times, sometimes on one push, but, after much back and forth, nothing would start it if unplugged. No response at all. At that point I'd drained the machine's internal battery.

Along the way I reset the PRAM and PMU to no avail and uninstalled Parallels RC 3.

Tonight I mirror the drive and tomorrow it goes to the Apple Store. I'll try leaving the battery out overnight for the heck of it. I assume it's a hardware issue. I certainly don't need this, but then, who does?

Update: Now the apple menu battery icon has a black X through it, and the drop down reads "No batteries available". The 'about this mac' profile showed "no battery".

Sounds like this is a common MacBook battery flaw. Sometimes it's a defective battery, sometimes a defective motherboard. I hope it's the battery of course, but when I push the battery charge button all five indicators light up.

Update 2/27/07: I work about five minutes from an Apple Store, so replacing the battery only took a few minutes. That did the trick. So what happened? Well, the battery might have simply been defective, but I wonder if there's not more to it. These LiOn batteries have internal computers and embedded operating systems that work to keep them on the right side of spontaneous combustion. Maybe that monitoring system detected some 'out of spec' behavior and shut down the battery -- for good. In other words, the noble battery terminated itself to save the mother ship. Mechanical apoptosis, in other words.

Or maybe it just blew a fuse.

Update 4/22/07: Rumor has it there's an association between battery death and running Parallels. Perhaps coincidence, but worth watching.

kw: apple, macbook, battery, adapter, adaptor, power, startup, start-up, bootup, boot-up