"Daryl" wrote in message
...
...I have never had a case break open on an AGM. Daryl

Then you haven't looked very hard.

http://nissandiesel.dyndns.org/viewt...60ab1 12d039d
"Problem: APC UPSs sometimes have a float charge voltage that is too
high and tends to cook batteries. Here's a pair of gel/AGM batteries
from a SUA1000 (not an XL) that have swollen so badly that I had to
disassemble the case and pry the batteries out of the metal cage: "