while installing a new battery it exploded why would this happen?

Dave, thanks for your answer I'll try this if I don't pay somebody else to fix it. I am not even going to open the hood anymore.Heck does anyone blame me?

No, I don't blame you. I was watching a poor tech years ago do a load test on a battery that happened to be frozen. I was about 5 feet away, he was under the hood. You don't soon forget that...and I wasn't the guy under the hood! Glad you are not injured. Good commercial for safety glasses...

I WAS ABOUT 2 FEET ABOVE THE BATTERY AT THE TIME OF THE EXPLOSION. GOT A SLICE ACROSS MY CHEEK AND BRUSED MY WHOLE LEFT HAND. A NICE SHADE OF YELLOW, PURPLE, AND GREEN. AND THE WORST WAS ON MY RIGHT HAND. IT TOOK A CHUNK OF MY FINGER (KNUCKLE SECTION) AND A SMALL CHUNK OF THE END OF MY PINKY FINGER. AND A WHOLE LOT OF ACID IN FACE (RIGHT EYE, MOUTH AND UP MY NOSE BURNING IT ALL) JUST LEFT A BAD TASTE IN MY MOUTH AND FEEL ON MY TEETH)AFTER SEVERAL BRUSHING AND THE EYE AFTER A LOT OF FLUSHING QUIT PUSSING UP. AFTER 3 DAYS AND IS FINE NOW (95% ANY HOW)

Goodness gracious. I spoke too soon about not being injured. What you experienced will stick with you physically a bit, but mentally far longer. Sorry to hear. I understand entirely. The explosion I witnessed was in 1994, and I remember it like yesterday...

no that's not it because before I put in the battery I had to replace the positive end, connecting to the battery. the ground was never disconnected at all. all I can think is that while trying to put the starter wire and the other power wire from the fire wall, one must of slipped out causing a electrical spark causing the battery gas fumes to go boom. But I just don't know. I 'm not going anywhere near that van for awhile. but thanks for your time, I'm glad some people will try to help others like you do.

what does your battery shored out mean ? or do you mean shorted out?