I was wondering, on the PHEV display, the battery is shown to be located under the seats. As it actually sits in the back, is it displayed like this for aesthetic reasons, or did they first plan to mount it there?

Good question. The first hybrid L405 (the short-lived, non-plug-in version with the 3.0l diesel rather than 2.0l petrol) had the batteries under the front seats, IIRC. But that was a while ago - the infotainment has had lots of new stuff since then.