It's a 120 liters fuel cell, made of aramid or kevlar with a dry safety disconnection system.
They are asking for tenders for a new cell. I saw something among the Car of The Future proposals they're asking for developing the car in time for 2013 and they mentioned specifically they allowed aramid and asked for filler foam. Don't know if the foam is used today (they should if they don't).
I wonder if the fuel tank is behind the axle (or something very strange happened during that crash). I know some American cars used to have this layout, The Ford Pinto did that until 1980, that I know. Some GM trucks had the same problem until the end of the 80's. I don't know if people here remember the lawsuit against Ford because of that, but I'm sure there was one.
Here's the vid:
http://www.youtube.com/watch?feature=pl ... wUvMKUlFLo