Do you mean why there is wiring to the LCD segments inside the battery icon? Well, if there was not, these segments wouldn't be too useful.
This is something typical for all LCD screens. You integrate visible and invisible wiring on the same plane. Hence you need some openings in the visible parts, if you have something controlled separately inside them. There has to be a small opening between the segments of a 7-segment digit, for example, or you can't turn the center bar on.
If you look at the top display of a 40D, for example, you'll see that there's something else, since the image quality icons are completely enclosed by a frame. There's not a single opening in that frame. But turn the camera off and the trick becomes visible immediately, since you can then see that the frame is printed, not a part of the LCD itself.