BMW i

[JRP3]

For comparison the Model S battery energy density is 150wh/kg and it looks as if the i3 comes out to 96wh/kg. They had to take as much weight off the car body as possible if they couldn't improve the specific energy of the pack.

 

[WarpedOne]

Is there any info on i3 battery internals?

 

[JRP3]

No real specifics but this has some detail on the configuration and weight: http://www.greencarcongress.com/2013/07/bmwi3-20130710.html

The BMW Group has planned and developed this battery to last for the full life of the vehicle. The battery pack is mounted flat in the Drive module and weighs approximately 450 lbs (230 kg). The battery casing and its model-specific attachment systems were developed by the BMW Group to provide the high-voltage battery with extensive protection against environmental factors and in the event of a crash.

 

[Kipernicus]

No real specifics but this has some detail on the configuration and weight: http://www.greencarcongress.com/2013/07/bmwi3-20130710.html

This linear power delivery extending into high rev ranges can be attributed to a special electric motor design developed exclusively for the BMW i3. A specific arrangement and dimensions for the components used to generate drive produces a self-magnetizing effect only otherwise induced by reluctance motors. This additional excitation causes the electromechanical field formed by the current supply to remain stable even at high revs. The maximum revs of the motor developed for the BMW i3 – known as a hybrid synchronous motor on account of its specific combination of properties – are 11,400 rpm.

What does all that mean? And how does it compare to Tesla's motor?

 

[JRP3]

Tesla's motor is good to around 14,000RPM I think.

 

[qwk]

Tesla's motor is good to around 14,000RPM I think.

16k, and there was talk around the time that the Performance version first came out, that Tesla was working on increasing that a few thousand rpm.

 

[theganjaguru]

I just got an email from BMW today about the i's carbon fiber frame. It makes me wonder if carbon fiber frames are in the design for GEN III and maybe even model X...

 

[stopcrazypp]

I just got an email from BMW today about the i's carbon fiber frame. It makes me wonder if carbon fiber frames are in the design for GEN III and maybe even model X...

Unlikely. There was speculation that Gen III might even switch to steel frame to save cost from aluminum. But given Tesla's current familiarity with aluminum, they'll probably stick with aluminum in the time being.

 

[renim]

given that spaceX uses both carbon fiber and aluminium, I'm sure they have good expertise to judge the various merits.
However for automotive use, the toughness of aluminium would generally be more useful than the strength of carbon fiber.

 

[Doug_G]

Unlikely. There was speculation that Gen III might even switch to steel frame to save cost from aluminum. But given Tesla's current familiarity with aluminum, they'll probably stick with aluminum in the time being.

Yesterday Elon called the steel insert in the Model S B pillar a "kludge", and said they could have done it with just aluminum. So I doubt they'll do anything else on Model X

 

[tommolog]

Some new i3 interior pics:

 

[anticitizen13.7]

For comparison the Model S battery energy density is 150wh/kg and it looks as if the i3 comes out to 96wh/kg. They had to take as much weight off the car body as possible if they couldn't improve the specific energy of the pack.

It occurred to me that this means that Tesla could in theory design a Honda Fit sized EV with 200 miles of range. The Fit is about a foot longer than the i3, and Tesla would not have to accommodate a range extender. The superior energy density of the Tesla pack seals the deal.

The U.S. market generally tends to view small cars as econoboxes, but the rise of brands like Mini have changed that to some extent. I'd really like to see Tesla go after the subcompact hatch market at some point after G3. In much of the world, a small car that can navigate narrow streets would be welcome.

 

[gameon]

Some new i3 interior pics:
View attachment 25614

I like the trunk area in car, and backseat looks tight for 6 plus...

I think BMW i3 series has pretty chance competing with gen3 of tesla given 3-4 years of head start.

 

[stopcrazypp]

I like the trunk area in car, and backseat looks tight for 6 plus...

Well it's a 4 seater so that's to be expected. Trunk looks okay, but looks quite high. Do they have an empty compartment under there like the Model S?

 

[tommolog]

Don't believe so. The motor and power electronics are there as well as the range extender if the car is equipped with one.

 

[stopcrazypp]

Don't believe so. The motor and power electronics are there as well as the range extender if the car is equipped with one.

You are right. Looks like the rear of the car is too short to fit a compartment there with the motor being there; Model S can fit a compartment because it is much longer in the rear. But it looks like the i3 can probably fit a compartment in the front. Will the production version have a "frunk" like the Model S?

 

[tommolog]

Yes, I believe it will but it will likely be small. I suspect it will be about the size of a small to medium sized backpack. This is a small car. 157.4" in length. The Model S is 196" long so basically cut the front of a Model S at the base of the windshield! Very different cars but both will play an important role in EV adoption I believe. The Model S is already doing it but don't discount what the i3 can do to help expand public acceptance of EV's especially in Europe.

 

[gameon]

Well it's a 4 seater so that's to be expected. Trunk looks okay, but looks quite high. Do they have an empty compartment under there like the Model S?

most probably because small range extender generator will on back (top of the electric motor)

 

[tommolog]

The range extender will sit over the rear axle to the right of the electric motor, not above it.

 

[fastcars]

I think people are aware of EV long ago but price and practicality lagging.

Also i3 comes from known brand, and affordability makes pretty compelling argument (range extender is not hybrid but really good solution)