Chevrolet Bolt: 55 Pre-Production Cars Made And Exceeding 200 Mile Range Target

[JohnSnowNW]

Without other cars to compare to, there is not much I can say. For eg. for such a large car, it has inadequate headroom. We don't know if that is the best possible or it could have been better.

The headroom limitation is a design element that is unrelated to battery placement. Yes, there is a lack of EV sedans, but I think it's pretty telling that the 85D isn't taking much of a hit compared to the other EVs on the market. The 85D is only 24MPGe (combined) less than the i3, despite weighing nearly 2000 lbs more and having far greater performance.

 

[ebwb]

The headroom limitation is a design element that is unrelated to battery placement. Yes, there is a lack of EV sedans, but I think it's pretty telling that the 85D isn't taking much of a hit compared to the other EVs on the market. The 85D is only 24MPGe (combined) less than the i3, despite weighing nearly 2000 lbs more and having far greater performance.

The battery in Model S takes up vertical cabin space, and as a result, I find it more claustrophobic in the back than with comparable sedans like E-Class or 5-series. Most cars have rear seats with "wells" to put your feet in; with Model S, my knees become uncomfortably high. If you measure the distance from the floor mats to the headliner, it's a lot less in Model S. Of course, the upside of a flat -- albeit high -- floor is that the middle passenger doesn't have to contend with the transmission tunnel hump.

For a small car, a tall-ish hatchback is the way to go, IMO. A sleek coupe-like profile is cool, but it's hugely impractical on a small car--ever try sitting in the back of a Mercedes CLA?

 

[EVNow]

Exactly. Maybe there is a better way to organize the batteries than a skateboard design - something that increases passenger comfort by placing some cells under the seat instead of under the feet.

Flat battery is great for battery exchange - which aren't popular.

 

[stopcrazypp]

S is not exactly an efficient car. Not sure what we are talking about here.

It is one of the largest (both outside, inside, and cargo-wise), highest performance (no low rolling resistance tires for example), and has the highest capacity battery of the EVs out there (pack alone weighs roughly 1300 lbs). For the specs, it is actually quite efficient. The 70D now gets 101 MPGe, edging out the 2011-2012 Leaf at 99MPGe. You have to look for cars 2-3 size classes down to look for significant improvements.

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Without other cars to compare to, there is not much I can say. For eg. for such a large car, it has inadequate headroom. We don't know if that is the best possible or it could have been better.

A quick look at the design already tells you the reason for the lack of headroom. It has the same sporty shape of coupe-like sedans like the CLS and A7. If Tesla went with a traditional sedan profile (like an E-Class/S-Class or A6/A8) it would have better headroom.

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For a small car, a tall-ish hatchback is the way to go, IMO. A sleek coupe-like profile is cool, but it's hugely impractical on a small car--ever try sitting in the back of a Mercedes CLA?

While I am okay with a traditional hatchback shape (like Mazda 3 hatchback for example), I do not want a "tall-ish" one like the Bolt. It simply looks ugly (and if the Model 3 looked like that I doubt it can sell 500k copies a year). I do not expect Tesla will go with a coupe-like style for the Model 3 like with the Model S, but rather in the worse case go with a sedan-like profile (like the 3-series it targets).

 

[JohnSnowNW]

The battery in Model S takes up vertical cabin space, and as a result, I find it more claustrophobic in the back than with comparable sedans like E-Class or 5-series. Most cars have rear seats with "wells" to put your feet in; with Model S, my knees become uncomfortably high. If you measure the distance from the floor mats to the headliner, it's a lot less in Model S. Of course, the upside of a flat -- albeit high -- floor is that the middle passenger doesn't have to contend with the transmission tunnel hump.

For a small car, a tall-ish hatchback is the way to go, IMO. A sleek coupe-like profile is cool, but it's hugely impractical on a small car--ever try sitting in the back of a Mercedes CLA?

It's been touched upon, but as I said, the flat battery is not negatively impacting the interior space. That is simply due to the design of the body. Nothing was stopping Tesla from going with a different design than the sleek sporty hatchback. If the battery is not flat, you are going to lose interior space somewhere...you can minimize the loss by placing it in "dead" areas inside the cabin...but there aren't enough places in the car to store batteries in an EV that gets 200 miles, and is the size of a sub-compact.

There is very little doubt that an EV designed from the ground up will be more efficient (all-around) than one that was designed as a shared platform.

 

[EVNow]

There is very little doubt that an EV designed from the ground up will be more efficient (all-around) than one that was designed as a shared platform.

In theory yes - but not necessarily in practice.

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A quick look at the design already tells you the reason for the lack of headroom. It has the same sporty shape of coupe-like sedans like the CLS and A7. If Tesla went with a traditional sedan profile (like an E-Class/S-Class or A6/A8) it would have better headroom.

They can get better backseat space by reorganizing the battery to be not flat. No need to reshape S.

 

[JRP3]

If they took out the cells in the rear foot well area and just made the top of the pack dip down in that area they could drop the rear seat a few inches, but I bet most buyers would rather have the extra range.

 

[SmartElectric]

There is very little doubt that an EV designed from the ground up will be more efficient (all-around) than one that was designed as a shared platform.

Disagree.

My Smart ED is an efficiency king in the city, not because it was designed as an EV in mind, but that the shared platform it sits on is perfectly designed for the task of short city commutes and trips.

A shared platform can be designed with every bit as much functionality, practicality, performance and other metrics as an EV with dedicated design, provided the manufacturer has the battery technology necessary to do so. That is the primary differentiator.

Where to put a large capacity battery is a consideration when manufacturers decide to compete with Tesla. Hopefully soon.

 

[JohnSnowNW]

Disagree.

My Smart ED is an efficiency king in the city, not because it was designed as an EV in mind, but that the shared platform it sits on is perfectly designed for the task of short city commutes and trips.

A shared platform can be designed with every bit as much functionality, practicality, performance and other metrics as an EV with dedicated design, provided the manufacturer has the battery technology necessary to do so. That is the primary differentiator.

Be that as it may the Smart ED is less efficient than both the BMW i3 and Nissan Leaf...two vehicles built specifically as EVs. Then there is the fact that two shared platform vehicles, Fiat 500e and Chevy Spark EV, both have less interior volume than their ICE counterparts. The Smart doesn't, for some reason, but that seems to be the exception rather than the rule.

Any battery technology that would allow greater performance/efficiency in a shared platform, would do the exact same for a dedicated one.

 

[stopcrazypp]

They can get better backseat space by reorganizing the battery to be not flat. No need to reshape S.

That's changing the subject. You were talking about headroom. No amount of reorganizing the battery will help that on the S because the styling is the core problem. Even if they don't have a battery at all, the slope of roof makes it so you simply will never match the headroom of a typical sedan.

You can improve knee room and seating position by scooping out the foot well as michaelwb mentions, but that doesn't really help you on headroom. The rear seats already have a charger under them, so the area you scooped out will have to take up space elsewhere, so doing so doesn't change overall interior volume.

I should note however, this is a separate discussion from the whole dedicated vs non-dedicated thing (you can have a dedicated EV platform that doesn't have flat batteries).

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The Smart doesn't, for some reason, but that seems to be the exception rather than the rule.

The Smart doesn't because it has a "sandwich" platform design, which already had an area under the floor (designed to let the engine slide under in a crash). Such a "sandwich" design is naturally fit for EV usage because it is a perfect space to put the battery. However, again, what it doesn't have vs a dedicated platform is it doesn't use the battery as a weight saving stressed member.

 

[JohnSnowNW]

The Smart doesn't because it has a "sandwich" platform design, which already had an area under the floor (designed to let the engine slide under in a crash). Such a "sandwich" design is naturally fit for EV usage because it is a perfect space to put the battery.

Ahh, wasn't aware of that, thanks.