I just got a 97 528i with 98k miles that was hit in the backend. We have been repairing it and now we are soon to finish, the battery is dead. I went to start it tonight to move it and it wont start. So we put the little jumper pack on and tried that and it wouldnt even turn over. So we put the bigger heavy duty charger on the battery and left it for a while and tried it again and still no turn over. All the lights on the dash come on as usual but just wont start. We tried jumping it with my dads car and that didnt help. im kind of stuck. We have the battery out now and going to leave it for an hour or so (I read something about an immobilizer). If that doesnt work i read something about a ignition switch also. My only concern is that the battery is a BMW one so im not sure if it is the original and just REALLY dead or what. But the light on it is green, meaning it is healthy so..im not sure where to go now. Any suggestions would be appreciated.

Update. Battery is in fine condition.

HELP! The battery is in full working order, but still nothing. I turn the key and everything lights up but just wont even turn over or make any noise.