What I refer to as "T-Bone" battery packs have been a popular battery layout in several electric vehicles.
The Tropica had the batteries right down the middle like that, as do several NEVs.
The
XR3 - a home-built Hybrid or Electric, from plans, has a tube straight down the middle, with spare batteries across the front.
Batteries have to go somewhere.
The most popular configurations tend to be:
1) T-Bone/center tube
2) Floor Pan/undercar
3) Sunken trunk/gas tank replacement (great for conversions)
A t-bone or center tube battery configuration is nice for hybrids, because it still allows for room next to or around it for the fuel and exhaust systems the engine needs.
For a Battery Electric Vehicle designed from scratch, a flat pan of batteries under the car works great. There's no exhaust system or anything else to get in the way of a battery case.
Home conversions usually put batteries in/under the trunk, or where the gas tank was. May as well make use of what space you can!
Cars like the Tesla Roadster have the batteries right behind the seats. Even though the Tesla is all electric, it is so low to the ground (and the body is designed by another company) that the batteries couldn't go under it. (My Metro has a bigger trunk than the Tesla!)
So, I would have to say that the battery configuration of the Volt is definately a compromise. The batteries have to go somewhere, and the hybrid design limits battery location, due to ICE components. Other EVs with t-bone batteries tended to be two-seaters. Who cares if the console between the two front seats is a little large?
Can't seat a fifth person in back or have as much fun at a drive-in? Might be a problem.
Here's the Tropica t-bone.
As you can see, the center console is a bit thicker than on most gas cars, but it doubles as an arm-rest, rather than being obtrusive.
