Is something wrong with my ipod battery?

First, reset and restore, as bac suggested.

After that, you're looking at a hard drive or hard drive cable issue.

One of the best methods to diagnose a failing hard drive is to listen to the drive. If you put your iPod up to your ear, you should hear a smooth-sounding whirr of the hard drive spinning. Any loud clicking or grinding sounds may mean that your iPod's drive is failing. If you don't hear anything, the drive is not getting power or is very damaged and can't spin up. In this instance, replacing the hard drive cable first is a good idea. Then, if the problem persists, replace the hard drive. Browse our hard drives and check out our iPod ID page for compatible drives.

Good luck!