I'd do what aspergerguy said, and see if it charges with the flasher utility. (I think I'd try that before disassembling it, but that's water under the bridge now.) The thread he pointed out has plenty of help in it to get started.

Unfortunately, I have to add that this is the manner in which my first N9 died, not to be revived. It would flash, but never turned on again. I was able to save important data with the "fixing MALF state" procedure and exporting and mounting the phone's partitions.