Dead Battery- Latitude D820

Hi,

The battery on my laptop died today and will not charge.  I can't unplug my computer from the wall without it shutting off, so it's running on AC power only at this point.  I was wondering if a new battery would be covered by Dell, and didn't know where to find that out.  I'd rather not have to pay $150 or more for a battery that (according to reviews and my own experience) doesn't last longer than 1.5 years.  I looked up my warranties and it says I have Next Day Business Support, so I don't know if that will cover it.  Sorry, I honestly don't know much about any of this stuff, I was just hoping that Dell would be able to ship me another battery free of charge.  Can anyone help me out with how I may find this info out?

Thanks,

Mike