Do laptops need a battery to run? No, they don't. One of my old work laptops had a bum battery that couldn't hold a charge, so it basically was a desktop. Now as far as the hardware being in place, that I'm not sure about. I know I've started up my laptop without the battery installed when I was trying to determine if the battery was shot, but I don't know if there has to be a battery connected, good or bad, for you to install the OS.

Have you tried checking on eBay for a used battery?