iPod Shuffle 4G won't charge.

Hello, well, a friend gave me an iPod Shuffle she never used. She had it for four years in its box without open it. Since yesterday it's been plugged in to the computer and nothing but a orange light is showing, I can sincronize it with iTunes, use it as a storage device, but when I unplugged it the orange light fades. (Which I know it's because it's no longer used by the computer). So my question is, is the batery death because the long nap`of four years? By now it's been charging like 18 hours. Thank you!