Battery relocation- Does anyone know of an actual hydrogen sulfide explosion incident?

I have had a couple cars with trunk mounted fuel cells, fuel pumps and batteries. Both definitely had aluminum firewalls between the trunk and passenger compartment. A box is then not required, but a very strong battery mount IS! My hold downs are welded to the battery tray (j-hooks are not legal) and the tray is thru bolted to the frame, not just the trunk floor.
The trunk mount battery also requires a rear shut off, and since moronic nhra rulez mandate it on the stupid (pos) side, I had to have a solenoid to shut off the one-wire alternator.