8 month old 6V battery dead

[JimNNN]

I (prematurely) bought a large 12 volt battery for a '72 Thunderbird I was about to buy last year...but the deal went south when the seller gave me a song and dance about the title status of the car (and fibbed a couple of times) so I'M stuck with the battery, and the only place to store it is on the floor of my storage unit. My head knows that the concrete floor vs. battery life thing is a myth, but my heart doesn't, as legends die hard for me. I have the battery on the floor, but it's resting on a half inch thick plastic grate (might've been a license plate holder of some sort) and have some black sheet poly material under that. I'll probably eventually put the battery in my '65 T-Bird or my '06 T&C minivan, whichever gives out first.