When you lift the battery cover up, it may appear that there is damage to the plastics. This is not the case, it is simply the underside of the image silkscreened on the cover and is no cause for alarm.
If you look closely at the battery cover, you will see a small representation of the default desktop picture that appears on the iBook screen. The other colored plastics have no image behind them. This is normal, we wanted to give the battery cover a unique appearance from the rest of the plastics.
The following image shows the top of the battery cover. While the Tangerine iBook battery cover has been used for example purposes, the Blueberry cover has a similar image on it.
Figure 1 iBook battery cover