The carbon fiber tanks are a little bit bigger and heavier than gasoline tank, is that what you mean?
They put them under the rear seat now because it's the safest place and they really don't want the PR from a car exploding after a crash, but it's not so big there aren't other places it can go.
What hydrogen system are you talking about? The ones I've seen all involve bulky tanks still, with really poor options for placement.
The carbon fiber tanks are a little bit bigger and heavier than gasoline tank, is that what you mean?
They put them under the rear seat now because it's the safest place and they really don't want the PR from a car exploding after a crash, but it's not so big there aren't other places it can go.
The designs I saw had like 3 severely limiting other capacity.