Simultaneous failure of two 2400 batteries???

[Paul Nelson]

Hi, Listers,
	My friends have a 240 G3 2400 which came up with a problem after
working nicely on two batteries in a school situation for 4-5 months.  He
would charge the batteries every night, and the child would use the machine
on battery the next day.
	All of a sudden, both batteries register as dead, and the machine
still works nicely on AC. If it isn't the batteries, is there an easily
replaceable part which handles the power from the battery into the system?
	 Also, there has been a screw rattling around in the machine for a
while.  TIA.
Paul Nelson