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GM ... flatten the battery pack. The Volt is already small ... the T design just takes up valuable room in the cabin (and the 5th seat is really a joke IMO).
 

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They did. It's called the Bolt EV.

I'm sure they never thought of that :)
btw, your PM box is full, but the buyer of my Spark wants to keep the Bosch unit. Sorry.
 

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I think in the future, we will all look back on the T-shape for batteries and say, "Not sure why they didn't put the pack under the cabin". I think in 2008 the only way GM could see how to build a strong pack management system that was relatively efficient was to do so using a relatively stocky cell, allowing for the coolant to get to all parts of the cell with little extra plumbing.

I saw a picture of an early automobile and it had a tiller like a sail boat instead of a steering wheel. Early designs frequently aren't optimal moving forward. But pretty soon the engineers realize the benefits of one particular design and everyone coalesces around it. Hence the Bolt following in the footprints of Tesla.
 

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I'm guessing going forward from the Bolt that will be the configuration of choice. I saw a Tesla chassis and just stood there and was amazed at how elegant and functional it looked. Dare I say it, is was "dam sexy".

Not sure if it cost more to build one over the other (if that's any consideration) but the skateboard design seems to be the future.
 

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Early designs frequently aren't optimal moving forward. But pretty soon the engineers realize the benefits of one particular design and everyone coalesces around it. Hence the Bolt following in the footprints of Tesla.
GM designed the "skateboard" many years before TM copied it. It took years to develop the right sized cell to fit in that design.
 

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Actually, the T-pack is a follow on from the EV1. I feel the T-pack is a superior layout over the flat-pack below the floor. If your interest is in protecting the battery from collision damage, having it in the center of the vehicle is ideal. The deep center tunnel also adds a great deal of body stiffness to the Volt. This higher body stiffness also balances out the large opening for the rear hatch, which I feel makes the Volt much more useful over a small trunk opening.

The rear "T" section of the battery is protected by the body stiffness present for the rear suspension attachments. Most modern vehicles put the fuel tank near this same location for similar reasons.

The T-pack also allow the designers to drop the passenger space down keep the height of the vehicle lower for improved frontal profile and a better aerodynamic design. The flat-pack probably moves at least the front passengers higher requiring a taller roof.

If I recall correctly, having the battery low to the road surface has created some damage issues for Tesla which pushed them into adding some shielding to prevent compromises to the battery pack (I won't type the F word).

To me, giving up a low use center rear seat is a small sacrifice for a better overall design. I just wish there was more rear seat leg room to make the other two rear seating positions more comfortable.

VIN # B0985
 

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The issue as I see it is the Volt uses a standard vehicle chassis that was modified to accommodate a battery. GM felt that a T shape was the best way to accomplish this without compromising the crash performance of the standard vehicle chassis.

The Bolt EV on the other hand is designed from the ground up to be an EV. The battery is designed to be part of the vehicle structure.
 

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GM designed the "skateboard" many years before TM copied it. It took years to develop the right sized cell to fit in that design.
Well, GM's skateboard was a hydrogen fuel cell design, not BEV, and they never commercialized it. I'm not sure it's fair to say Tesla just copied it. And the type of cells Telsa uses (18650) have been around in laptops since the 90's... it wasn't a size issue. Tesla waited until the energy and power density (and cost) of those cells made it possible for a decent electric car.
AZ EV Driver said:
The T-pack also allow the designers to drop the passenger space down keep the height of the vehicle lower for improved frontal profile and a better aerodynamic design. The flat-pack probably moves at least the front passengers higher requiring a taller roof.

If I recall correctly, having the battery low to the road surface has created some damage issues for Tesla which pushed them into adding some shielding to prevent compromises to the battery pack (I won't type the F word).
I park next to a Model S at least once a month. Somehow, their roofline is actually a tad lower than the Volt, even with their pack in the floor. They did a great job on packaging! And that battery road damage event was a pretty freak accident (hitting a large chunk of a broken/detached tow-hitch just right), and I think only cars with the air suspension were really susceptible (car lowered it at high speed for aero reasons)... heck, I've heard of people running over tree branches and rupturing their gas tanks, can't protect against everything! I do agree the T-design is probably safer, but I think a floor pack can be made pretty close to it and allows more cabin space... there's a reason most EVs have chosen that route. What I'd love to see in Volt gen3 is 1/3 of a Bolt pack in floor. Since it's only 1/3, you could position it in the center of the car so it would be just as protected as the T, yet allow more cabin space.
 

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The issue as I see it is the Volt uses a standard vehicle chassis that was modified to accommodate a battery. GM felt that a T shape was the best way to accomplish this without compromising the crash performance of the standard vehicle chassis.

*snip*
Perhaps that's the case for Gen 2, but was it the case for Gen 1?
 

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The issue as I see it is the Volt uses a standard vehicle chassis that was modified to accommodate a battery. GM felt that a T shape was the best way to accomplish this without compromising the crash performance of the standard vehicle chassis.

The Bolt EV on the other hand is designed from the ground up to be an EV. The battery is designed to be part of the vehicle structure.
My only argument to this is the Spark EV was built on the Spark ICE chassis, has a flat floor and more EV range than the Volt...Spark EV was offered before the Gen2, many had hoped the T-Shaped battery was replaced by the flat floor forever...With all that being said, if GM released the Gen2 with the only difference with today being no rear floor hump, I don't think it would drastically change sales figures...

At that silent Bolt EV driving event that you went to, there was only one criticism which was that it's a very narrow car...Many who are excited about the prospect of going from a Volt to a Bolt EV for the increased rear room might be disappointed...
 

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The OP has a great point and goes along with what we all already know. The Volt is a small car, and even though the Volt is AWESOME, it is still a small car. Using the T pack only exacerbates the problem by making a small car smaller. This is why many of us have been clamoring for a larger vehicle similar to the Volt in an SUV form for the added space. I really, really, like my Volt, but having the same setup in an SUV would allow for much more space. Personally, I believe they don't want to cannibalize sales so that is why it is only in small cars at the moment.

And yes, I am fully aware of other offerings like the Pacifica and the never arriving Outlander...
 

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The cell dimensions used by the Volt would require a rather thick floor if used in a skateboard configuration. This is OK in a CUV like the Bolt but would not in the Volt. Teslas are able to use the skateboard configuration because they use much smaller cells derived from laptop battery packs.

The Cadillac CT6 Plugin has a conventional floor even though it uses the same battery as the Volt. This was accomplished by stacking the battery vertically behind the rear seat. The downside of this is it reduces trunk volume.
 

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Yeah redesign a car that was just redesigned. That's the ticket.
With the 4-6 year life span of many vehicle designs nowadays, wouldn't now be about the time to start design on Gen 3? (Hint, hint, GM!)

A Bolt style, 70-80 mile pack, that only sits under the rear/inside portion of the car, I think would be ideal for Volt.
 

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Hence the Bolt following in the footprints of Tesla.
GM demonstrated a skateboard design well before Tesla was a thought.

I kind of like the airplane-cockpit style of ELR. The open design of Model 3 is just too modern for my taste.

I like a lot of cubbies and such for stowing my gear. And my laptop fits perfectly behind the driver's seat. Having stuff slip-sliding around is no way to run a ship.
 

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Unveiled at the 2002 Detroit auto show, it was supposed to be GM's radical vision for a truly futuristic car. Freed from the tyranny of the internal combustion engine, GM was going to revamp the entire automotive paradigm with this, it's most audacious concept car ever. Behold, the billion-dollar Skateboard! GM actually called it "Autonomy," even using nonsensical capitalization to help the dim-witted understand that the first four letters of autonomy spell "auto." That billion-dollar number was thrown around to convince people that GM was serious about making some sort of play in the green vehicle space – which, if you'll remember – didn't actually exist in January 2002, nearly two years before the second-generation Toyota Prius ignited the category.

A drivable concept car, the Hy-wire, was unveiled later in the year.

GM autonomy-skateboard.jpg
 

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The cell dimensions used by the Volt would require a rather thick floor if used in a skateboard configuration. This is OK in a CUV like the Bolt but would not in the Volt. Teslas are able to use the skateboard configuration because they use much smaller cells derived from laptop battery packs.

The Cadillac CT6 Plugin has a conventional floor even though it uses the same battery as the Volt. This was accomplished by stacking the battery vertically behind the rear seat. The downside of this is it reduces trunk volume.
Pretty sure the Bolt is using similar cells as Volt and they fit the pack in the floor. Leaf too (though lack of a real thermal system made that easier), and Fit EV, etc. Almost every other BEV than Tesla uses the large flat pouch cells and yet manages to fit them in the floor...

I mean, surely the Bolt pack was in development when gen2 Volt was. I'm really surprised they didn't work together on the pack... full version for Bolt, 1/3 version for Volt. Guessing gen2 was too far along in development when Bolt started though...
 
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