battery charging and death

[Ed Kellock]

My Coupe GT had a new battery last July.  Over the last couple months the car has sat unused for longer periods of time.  It required a jump and then would be okay until it sat again for several days.  This is generally not a common problem for the car.

According to Mike LaRosa and "Tony & Lillie", 12.8 is the baseline heathly battery charge.  After charging mine to about 13.03 on a 2-amp charge, it settles to about 12.3 when the charge is removed and then slowly starts to trickle down, the last reading was 11.85.  So I'm think it's dead, Jim.

So did I kill it?  I was going to use the KnowledgeBase item to check for a drain on it, but I figure that's moot until I get a battery that will hold a charge first.  

Do peiods of inactivity kill a battery?  Or just an already compromised battery?  Would a constant slow drain kill it?  Did I just get a bad battery from the get-go?

I've removed it and will be heading out to exchange it later today.

Thanks,
Ed