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Why the Tesla Model 3 will look like the Chevy Bolt

I’ve been following the conversation around who will be first to market with an affordable 200 mile EV.  (Somewhere in the $30-40k range).  There has been a lot of rhetoric about who will do it, who has better engineering?  Can Tesla do it on time given that their track record for delivering on time is so poor?  Will GM do it?  Or do they not have enough organizational vision to get there?  Nissan seems to be serious about it, but the Leaf, with its 75 mile battery range seems a long ways away.

I have a much simpler case to make beyond people’s belief systems about who to trust in the BEV world.  Which is:  What will the first generation of affordable 200 mile electric vehicles look like?  Well pretty much like the Chevy Bolt.

No matter what side of the polarized view you may be on with respect to the Bolt.  Be it cool or hideous:  Your first 200 mile EV will probably take a shape very similar to it.  Let me explain in layman’s terms why.

1.)    Batteries are still very heavy and they take up a lot of room.

2.)    You want to be able to actually fit people in the car.

3.)    Oh btw:  Cargo room would be nice too.

4.)    Oh right:  The car needs to be affordable.  No all-aluminum or carbon fiber builds to compensate for battery weight

5.)    Wait a heavy car needs more batteries to move it?

So with today’s and I would even venture to claim the battery technology available in the next 2-3 years storage capacity, you have a fundamental design challenge.  Expect the Model 3 (That releases in the next 3 years) to look like a BMW 3 series?  Unlikely.  To understand why, let’s take a look at how different EV’s today have worked around the inconvenient challenge of the battery.

1.)     The Chevy Volt

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The Chevy Volt has a smaller battery (440lbs).  It puts it in a T shape, which means that passengers have somewhere to put their legs without making the car too tall.  That allows the Volt to have a sedan/hatchback design that still sort of looks like a normal car and fit 4.5 people (albeit tightly as a compact car would) and a little trunk room.

2.)     The Nissan Leaf

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The battery is under the car in a “skateboard” like configuration – it also is relatively “small” 660lbs.  So why does the leaf look like a small hot hatch and not a sedan?   Well, when you put the battery below the passengers, it’s an extra 6 inches of space that is taken away.  People still have to fit in the car.  So what to do?  Make the car a little taller, especially in the back to you can still fit people and little cargo in it.  Today’s battery tech means a small car like this with a 24KW-h pack only goes 75 miles.  There are marginal, but not major improvements in powertrain efficiency as you can see with the Volt improving by 25% or so, but nothing to get the car from 75 miles to 200 miles expect a bigger battery.

3.)     The Model S

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The Model S also puts the batteries under the car in a skateboard configuration.  So why does it look like a sedan and not like the Leaf?  Key engineering tradeoffs:  Very wide and longer wheelbase to put more batteries in.  That allows the Model S to get to 85Kw-h and get the 200 mile range.  To make up for this extra weight, the Model S uses aluminum in the body, but still weighs almost 5,000 lbs.  The longer wheelbase too means that there’s more room for people to fit in it, albeit in a more reclined position.  (Somewhere to put your legs)

A cool design for sure, but one that will not easily “shrink 20%” to a Model 3 size very easily.

The Punchline

Put another way, don’t expect the Model E or the Bolt or anything Nissan, Audi or BMW to put out to look like a sized down Model S.

Why?  Well a 20% smaller Model S (purely scaled down) means:

1.)    Nowhere to put the people.  (I have a Cadillac ELR, which lost 1 in of headroom from the Volt for design aesthetics and I barely fit in the front seat now and the back seat is basically non-existent)  Remember, this is with a car that has a T-shaped battery and not a skateboard battery)

 

2.)    Wait we have to use steel again to make it inexpensive?  That means we aren’t building as big a car or it’ll weigh too much.

 

3.)    20% smaller car doesn’t mean 20% smaller battery capacity to get the same range.  While weight matters, aerodynamics matter a lot more for distance driving.  A “smaller” car doesn’t always been less aerodynamic load, especially given how slippery the Model S is today.

 

The Bolt Concept is a demonstration of what it would take using today’s technology to package a 200 mile EV – it’s small and tall to make up for the fact that it needs some heavier materials and considers the fact that the battery will lift the entire car up by 6 inches, this is needed to leave room for people and cargo.  Maybe you don’t like the colors, or the use of chrome that GM has, but get used to the fact that an affordable 200 mile EV in the next 3 years will look closer to the Chevy Bolt than a 3 series BMW.

3 Responses to “Why the Tesla Model 3 will look like the Chevy Bolt”

  1. Jeff says:

    Very interesting comments – I agree with the size/weight/cargo space argument, but I wonder if in 2 years carbon fiber and aluminum vehicle manufacturing costs will have come down enough to help lighten the overall vehicle?

    I posted a link to your article over here to get some discussion going!
    http://www.mychevroletvolt.com/why-the-tesla-model-3-will-look-like-the-chevy-bolt

  2. Jeff says:

    Bah, sorry, wrong link.

    This is where I posted it: http://www.mychevybolt.com/forum/viewtopic.php?f=2&t=27

  3. MacDuff says:

    Yes, maybe so, but “punch line (2″ flies outta window if you take into consideration recent tech developments in metalurgy to this equation. Consider the following

    In brief: “The latest in a continuing series of research studies strongly suggest that steel auto body structures in the near future can be as lightweight as today’s aluminium bodies …”

    “Adding to a weight reduction of 35 percent in its initial FutureSteelVehicle design, the steel industry’s most recent studies boost the mass savings to 39 percent, compared to a baseline steel body structure carrying an internal combustion engine, adjusted for a battery-electric powertrain and year 2020 regulatory requirements. The optimized FSV body would weigh just 176.8 kg, putting steel on par with today’s aluminium production designs.”

    In terms of weight reduction utilizing aluminium, im also very curious to see what the F150′s aluminium body on steel frame fallout due to galvanic corrosion might turn into.

    Ref: http://www.worldautosteel.org/projects/future-steel-vehicle/steel-eliminates-the-weight-gap-with-aluminium-for-car-bodies/

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