Model S specs

[TEG]

They said 7800 cells for both 230mile range and 300 mile range...
7800/6831*53kWh = ~60kWh if the 230 mile range pack uses similar cells to the Roadster.

300 mile range / 230 mile range = 1.3x more energy needed.

2400mah * 1.3 = ~3120mAh per cell...

You can get 3000mAh cells today.
I guess with 7800 of them it would be ~1.25x or 287 mile range with ~75kWh.

(Still just guessing that current pack uses 2400mAh cells).

It doesn't seem much of a stretch to assume that 3200mAh would be available soon.
But can they stand up to the same stresses as the current cells?

 

[vfx]

Click through to the NYT story - lots of interesting nuggets.

Some sweet bits. love the deja vous in the naysaying. (but now each with a hint of backpeddling)

 

[dpeilow]

You can get 3000mAh cells today.

Nice. I bet there are some people on here that would pay ~$35k to upgrade to those.


In the NYT article, JB says:

The pack is within “technical reality,” given the experimental high-density cells Tesla is now working with, Mr. Straubel explained, adding that these cells could, with today’s technology, give the Roadster a range of 280 to 300 miles.

Yet 3000mAh comes out at 305 miles EPA already (simplistically).

 

[stopcrazypp]

Nice. I bet there are some people on here that would pay ~$35k to upgrade to those.

In the NYT article, JB says:
The pack is within “technical reality,” given the experimental high-density cells Tesla is now working with, Mr. Straubel explained, adding that these cells could, with today’s technology, give the Roadster a range of 280 to 300 miles.

Yet 3000mAh comes out at 305 miles EPA already (simplistically).

3000mAh cells still aren't very common yet, and it's unsure if the performance can match the more common 2400mAh cells. I don't think any big name brands are making 3000mAh cells yet. However 2800mAh is made by a couple of big name brands and 2900mAh cells are made by Panasonic.

2800-2900mAh means 285-295miles of range if you take 244 miles to be the range of the Roadster with 2400mAh cells. I think that was what Straubel was referring to (280-300 miles).

 

[Joseph]

"They said 7800 cells for both 230mile range and 300 mile range..."

I know very little about battery pack design, but I'd imagine the 230 mile and 300 mile range battery packs are not interchangeable.

The 300 mile range pack would need better cooling since it would have to deal with longer trips (probably taken at highway speed). Also, there are tradeoffs in cell design: energy density generally trades off with power capacity and a multitude of factors. Possibly, the higher energy cells require better care (and cooling) than the 230 mile cells because of these sort of trade offs in design.

Maybe they'll over-engineer the 230 mile range pack to leave room for improvements in the future - like 300 mile range cells?

And maybe I was exaggerating that they'll need "exponential" improvements. I'm a doubter!

 

[TEG]

When they say "experimental" it is possible that they mean commodity cells that haven't yet been tested in this particular application.

 

[dpeilow]

I found this quite funny:

Dick DeVogelaere, chief vehicle engineer for Magna International on the Ford battery car project, scheduled for 2011 production, was quoted saying “It would take a pickup truck to haul that battery around. It would probably weigh in excess of 1,000 pounds, maybe 1,200.” Mr. DeVogelaere also predicted that the cost would be three times that of a standard pack. “It’s all about mass,” he said. “If Tesla has a way to make it very light, maybe they can get there. But they would need some major breakthroughs — it would be difficult based on existing technology.”

Now, the existing Roadster pack is 450kg. Given that 1000lbs is 453kg, I hardly think you are going out on a limb there with that prediction, Mr DeVogelaere...


Furthermore, haven't we previously heard that the new battery improves the packing efficiency in terms of space and the mass of auxiliary systems?

The new cells that TEG found are 46g each, which means that 8000 of them weigh 368kg. Assuming even the same cell to total pack ratio for this Model S pack, that comes out at 550kg (coincidentally that's 1200lbs - I get the feeling someone has been doing their homework).

Now, given that the Jaguar XF weighs 1820kg, the Porsche Panamera weighs 1800kg and the Aston Martin Rapide is reckoned to weigh >1900kg, even with a 550kg pack the Model S has a lot of headroom against the cars in its class. A V8 with drivetrain weighs in around half that - so, a challenge, but hardly needing a pick-up truck.

As for the quote from the man from Aptera, that has to be way off.

 

[dpeilow]

Also, there are tradeoffs in cell design: energy density generally trades off with power capacity and a multitude of factors. Possibly, the higher energy cells require better care (and cooling) than the 230 mile cells because of these sort of trade offs in design.

Ah, the pesky power density.

Well, TEG's link says these cells have 0.5C max discharge. That would give a 44kW pack (I think), so I'll invoke the usual ultracapacitor buffer. :biggrin:

See, it could be built now. :wink:

 

[Cobos]

Still this does make it sound like the 300mile pack is probably going to be the most high-tech or cutting edge of the packs. And getting it ready just within a year after the regular Model S starts production sounds a bit iffy. I am so glad I only need the 160mile pack.

The big problem though for Tesla is in the image of the 300miles pack. Those buying that pack want the long range capability which I dare say is going to be ON the highway. Hence the difference between actual usefull range and claimed range is probably going to be biggest for that pack.

Cobos

 

[malcolm]

Should be optimised for EPA Highway rather than Combined? But that immediately suggests adding an extra 20-30% to the pack capacity!

 

[dsm363]

Just talked with someone from Tesla. Sounds like the 300 mile pack is at 50/50 for making it to production the first year. There will be a credited upgrade path for first year buyers to upgrade the next year, I was told at least.
Also, he said not to expect the options and such to be available until 4-6 months before production.

 

[Palpatine]

Based on my history with Tesla Motors (and the executive leather package) you cannot count on the options until the car is actually delivered. They are not guaranteed and there is no refund even if they end up as 1/3 of what the picture showed.

Tesla produces a great car and I am sure that I will love the Model S also. But at this point there is nothing to even discuss about the Model S. It is a total blank page and we are flying blind. The fact that I am a Model S customer, even after the executive leather issue, should tell you how much I like my Tesla Roadster.

It is just a killer car and I am willing to overlook the "little" issues.... like a $6,000 executive leather bait and swtich.

 

[dpeilow]

Plastics News - Tesla turns to metal for sedan

 

[Cobos]

Tesla produces a great car and I am sure that I will love the Model S also. But at this point there is nothing to even discuss about the Model S. It is a total blank page and we are flying blind. The fact that I am a Model S customer, even after the executive leather issue, should tell you how much I like my Tesla Roadster.

Though some are flying more blind than others Out here in Europe we don't even have any idea of the price of the Model S. Still to be determined.

I wouldn't like to buy any of the Signature edition Model S for that very reason, you don't really know what you end up with, and even with a full deposit they can change the price on you. Well that and the fact that the Signature is just too expensive as well.

Cobos

 

[Cobos]

Though I'd post some here.
I just got a flyer from Topline, what seems to be the current Oslo distributer of Tesla cars. I'm not sure if they want a full Tesla shop as well here in Oslo but currently they seems to be representing Tesla. They recently had a VIP event which I unfortunately was unable to attend. But a bit of time later I got a flyer with a good offer for the Roadster and some more information for the Model S.

It's in Norwegian so I've translated the whole list.

Model S starts delivery to the US market next year and for Europe it will be availbable from Q2 2012. It will be delivered with 3 different battery options 255km, 370km and 480km.
Specifications:
7 seats
Manufacturers estimated price: 500 000 kr ($84 750)
Aluminumchassis based on MB E-class
680L storage area (not sure if that is just rear or rear + front?)
0-100 in 5,6 secs
5 min battery swap
Foldable rear seats (60/40)
45 min quick charge allowing 80% recharge
17” touch-screen
1735 kg

Some of this was new to me like the chassis and the exact weight and storage space. The price as well was a bit unwelcome surprise, as that is above my original max level I can afford Hopefully that includes a lot of equipment or it comes down a bit.

Cobos

 

[Albern]

Thanks for the info Cobos.

If it isn't too much trouble for you, do you think it's worth scanning and posting the flyer; any interesting any new pics of the car?

That's an interesting point about Mercedes E-Class chassis.

Also, I know Tesla have been touting the ~$55,000 price tag (after government rebates); is that price of $84,750 been expected for the European market? I figured it would be a bit more expensive but not by that much.

 

[T@oo]

I think the US prices are always without VAT. Those $84.750 are including 25% VAT for Norway? If yes, that will bring it down to $67.800. Still a lot more. How about the luxury tax in Norway for cars?

I thought only the first prototype was based an MB chassis. I'm still 40 years too young to drive MB ...

 

[svaamaas]

There are no vat or any taxes on EV cars in norway atm, but I guess it will change when the goverment find out everyone are buying a tesla :biggrin:

Have been lurking around in the forum for a while; Hello everyone!

 

[Cobos]

I think the US prices are always without VAT. Those $84.750 are including 25% VAT for Norway? If yes, that will bring it down to $67.800. Still a lot more. How about the luxury tax in Norway for cars?

I thought only the first prototype was based an MB chassis. I'm still 40 years too young to drive MB ...

As Svaamaas mentioned there are no VAT on EVs or any pigouvian taxes on EVs. Which is why I'm a bit curious why it's so much more expensive. Obviously when the price is listed with 5 zeroes that is not the final price but I had hoped it would be closer to 400 000 and not 500 000. Regardless I suppose we'll see when it does get a final price.

Albern: No new pics and since this is a non-public flyer only intented for the VIPs invited to the event I'd rather not post all of it online.

Cobos

 

[TEG]

...Aluminumchassis based on MB E-class...

OK, so perhaps the concept car is closer to production intent than some of us thought. I had heard before that Tesla had planned for the chassis to be their own design "from the ground up", but using an existing / proven chassis could be more expedient.

1735 kg

3800+ lbs is starting to get a bit heavy considering the use of lightweight materials (aluminum chassis, li-ion batteries, etc.) but probably not too surprising considering all the luxury features they want to include.

This spec page for an existing E-class variant shows 1650 kg, so it sounds like the Model S expects to be around the same weight as the MB gasoline counterpart.

I guess an aluminum variation of an E-class chassis would be something special as the standard seems to be steel...

2010 Mercedes-Benz E-class / E550 - First Drive Review - Auto Reviews - Car and Driver

...Under the new skin is an entirely new steel unibody structure. A few sprinklings of aluminum are present in the front fenders, hood, radiator support, and steering column bracket, but the E-class remains a steel-intensive vehicle. Not surprisingly, overall weight is expected to increase from the 3740 pounds the company claimed for the previous E350...