The Top 11 Discoveries From the BMW i3 and i8 Unveils

By · August 02, 2011

BMW i3 and i8 concepts

As part of a small contingent of Americans who made it to Germany last week for the official unveiling of the BMW i3 and i8--the first cars set to be released under the new BMW i subbrand--I was given a tired and jetlagged glimpse into the incredibly complex world that is BMW i. In short, the subbrand represents a paradigm shift of everything from how cars are built, to what materials they use, to what kinds of impacts their construction has on the environment, to what kinds of tools they offer drivers.

While that may sound grandiose, after attending 7 hours of workshops and press conferences immediately after flying for 14 hours with no shower or rest to speak of for more than 28 hours, I can tell you with reasonably good clarity that it's true. If BMW pulls it all off, the launch of both the i3 and the i8 and all of the BMW i subbrand will represent something brand new in the automotive world.

Who knows how expensive these cars will be, but for many people--namely the young, affluent, urbanites, as BMW likes to point out--the cars will be worth it at any price.

There are many recent articles out there about the i3 and i8 unveils at this point, with's Tom Moloughney and Laurent Masson offering up a couple of the better ones, but after taking some time to let all the information settle in my own mind, 11 discoveries rose to the surface.

1The i3's Battery Pack Will Be Between 20 and 25 kWh

BMW i3 powertrain

To this point it has been assumed that the i3 would sport a battery pack in the realm of 16-18 kWh. However, according to BMW electric car engineer Patrick Mueller (and corroborated independently from another BMW representative for whom I did not catch a name), the all-electric i3 will have a battery pack that has a capacity between 20 and 25 kWh. Mueller also said that the allowable utilization of the battery pack will be much higher than 80%, likely close to 95%.

Given that the i3 has an estimated range of about 95 miles on a full charge, that puts it in the realm of 4.75-3.8 miles per kWh for efficiency. While those numbers are very good to reasonable for an electric car, they are nowhere near the efficiency of 5-6 mpkWh that some had been expecting. This has the potential to be especially disappointing to those of us who take it as common knowledge that a car built with an incredibly lightweight carbon fiber frame should excel in efficiency.

2The BMW i Connected Mobility Package Is Truly Forward-Thinking and Innovative

BMW i connected mobility

One of the workshops BMW offered after the unveils of both the i3 and i8 showed off the connected mobility package that BMW will include with every vehicle from the i lineup. This package takes the idea of navigation systems and driver assistance and blows it out of the box.

Not only does the software have the ability to calculate several different routes and options for charging stations along the way, as well as detours for traffic, it will also tell you when the car isn't likely to be the fastest route and when public transportation is. Suggested routes from a given starting point can consist of all public transportation to mixture of driving and public transport with a parking spot for your car at a charging station while you're traveling by bus or train. That's right: it's a system from a car company that happily proclaims that cars aren't always the best way to get around.

On top of this out-of-the-box thinking, the system also includes parking assistance that will park the car for you (something that Ford has started offering recently), traffic jam assistance that combines active cruise control and steering assistance up to 25 mph to steer and move the vehicle by itself, automatic braking and pedestrian crash avoidance, and remote conditioning (heating, A/C, charge timer, and battery preconditioning).

BMW has also started an investment fund called BMW Ventures to help developers create smartphone applications that connect directly to the BMW i mobility system and provide extended functionality, such as restaurant searching and reservation assistance, movie times and ticket purchase, sharing of parking spaces and much, much more.

3The i3 Will Have Incredibly High Visibility, But Not Nearly as Much Glass as the Concept

BMW i3

The i3 concept is a study in how much glass can be fit onto a single vehicle. According to Adrian Van Hooydonk, BMW's SVP of Design, the goal was to create a vehicle that allowed for unprecedented visibility: it has a glass roof, mostly glass doors and a glass rear hatch.

However, as much as that amount of glass is ultra cool in that futuristic sci-fi sort of way, there isn't a chance in hell it will make it through to production. In fact, in another workshop BMW was showing off the carbon fiber roof panel they plan on putting on the i3. Van Hooydonk did admit that the production vehicle won't have nearly as much glass, but said that regardless, the goal was to create a vehicle with higher visibility than any on the market.

4The i3 and i8 Are the End Brackets to an Entire Lineup

During the unveil, several members of the media pointed out that the i3 and the i8 are great for their own niche markets, but asked if BMW was planning on releasing plug-ins that would meet the needs of an average family.

Although BMW was tight-lipped and pretty cagey on the subject, they did offer up that the i3 is technically a four-seater and could carry most families, but eventually admitted that the storage space in the i3 wouldn't likely be enough. However, Dr. Klaus Draeger, BMW's Board Member Responsible for development, did remark that, "In between 3 and 8 there is quite a lot of room for additional vehicles." Apparently BMW is planning some sort of family vehicle in the i lineup for the future.

5The BMW/SGL Carbon Fiber Plant Is Quickly Scalable to Meet Whatever Demand Exists

Although BMW representatives couldn't be tempted to provide volume predictions, they did say that no matter how many i3s and i8s are demanded by customers they will be able to scale to meet that demand as required. According to Bernhard Dressler, Director of Body Development for the i3, the carbon fiber plant being jointly run by BMW and SGL Carbon in Moses Lake, WA, is very flexible.

"Although we cannot predict demand for electric cars in general, we have designed the carbon fiber manufacturing process to be very flexible on purpose," said Dressler. "So we could easily double the volume of carbon fiber output in just a couple of months."

6The i3 Consists of Two Distinct Modules Surrounded in Thermoplastic Skin

BMW i3 modules

Given the novel materials and design being used in the i3, BMW had to develop manufacturing techniques that previously haven't existed on the same build line or in the automotive industry at all. The base of the i3 is its all aluminum welded "Drive Module." This drive module also includes aluminum front and rear crumple zones.

BMW i3 thermoplastic body panels

A completely carbon fiber composite frame, called the "Life Module," sits on top of the drive module base and is attached to it by copious amounts of glue and a scant four screws. BMW says they have extensively crash tested this configuration to ensure it will remain intact in even the worst accidents. The carbon fiber frame itself consists of many different pieces of individually molded components that are glue-welded together and, in the case of a crack from an accident, can be cut out and replaced with the same glue welding process.

On top of this joined "LifeDrive" chassis, BMW hangs advanced thermoplastic body panels and glass.

7The i3 and i8 Will Have Parts Made From Hemp (and Other Renewable Resources)

Although the bulk of the i3 and i8 will be constructed of aluminum and carbon fiber composites, BMW has made a gigantic push to ensure that many of the vehicle's other components are made from renewable material using renewable energy wherever possible.

Eighty percent of the i3's aluminum is either recycled or produced with renewable energy and 25% of the weight of plastics used is replaced by recycled or renewable raw materials. Some of these raw materials include hemp (yep, the kind that's related to marijuana) sourced from Bangladesh.

In addition to the materials, BMW chose to site its carbon fiber plant in Moses Lake, Wash., in large part because the energy there is almost 100% hydroelectric and making carbon fiber uses a lot of electricity. That area of the US also happens to have some of the cheapest electricity on the planet at less than 4 cents per kWh.

8The i3 and i8 Are Better for the People Who Build Them

In addition to, and as a result of, the novel construction techniques, the workers who will be assembling BMW's i cars will be exposed much quieter work environments. There is no stamping of sheet metal and very little welding of metal at all. In fact, except for the aluminum drive module, the rest of the car has almost no metal in it.

Pushing this low impact work environment to the limit, BMW says the factories that will make the components for the i cars will have "optimized" workplace conditions with 50% less noise than a tradition assembly line and be infused with natural lighting.

9The i3 Will Be Able to Be Ordered as Either a LEAF or a Volt

It has been rumored for some time that BMW was planning on selling the i3 with a small range extending combustion engine as an option. Now that has been made officially official, and it's called 'REx.' REx will be a tiny, low displacement engine.

If ordered as an option, the range extender and fuel tank will be mounted in the rear of the vehicle next to and underneath the electric motor. It will not be connected to anything but a generator which will supply electricity to the battery and allow the car to be driven beyond the 95 miles of range between charges.

BMW wasn't able to address if the addition of the range extender would result in a decrease in size of the battery pack or whether or not the range extender option would be available in all markets, but nonetheless the addition of this feature as an option is something that sets the i3 apart from any competition. BMW representatives also couldn't tell me if the range extender would be available at launch, or if it would be coming later.

10With Carbon Fiber, BMW is The First Automaker to Become a Major Textile Manufacturer

Carbon fiber must be woven into textiles before being encased in plastic to make the composite material. BMW has constructed a gigantic textile factory in Wackersdorf, Germany, that exist for the sole purpose of making all the different types of carbon fiber textiles that BMW needs to build the panels for the i3 and i8.

BMW's Dressler, said that there are two different types of fabrics in four different thicknesses that the factory has to make depending on strength and weight requirements. The two fabrics have either crisscrossing patterns or unidirectional orientation of carbon fibers depending on what type of directional strength each structural piece needs.

In order to meet the legal requirements of Germany, BMW has now become a major member of the Bavarian Textile Manufacturing Association as well. What other car manufacturer can claim that?

11The BMW i8 Has Become a Bit Tamer

BMW i8

As Laurent Masson pointed out in a recent article, the i8 concept is less of a performance monster than it used to be.

BMW has removed one of the two electric motors from the vehicle and downgraded the combustion engine from an efficient diesel to a heavily turbocharged 1.5 liter, 3 cylinder engine putting out 220 horsepower. That combustion engine is hooked up exclusively to the rear wheels. The remaining electric motor is the same 129 hp motor found in the i3 and exclusively powers the front wheels.

Even with the reduction in power, together both powerplants can pump enough power to all four wheels to get the vehicle to 60 mph in about 4.5 seconds.


· dpeilow (not verified) · 6 years ago

Point 1 just shows how aerodynamics play the bigger role at highway speed.

· · 6 years ago

Well done Nick. Your line "In short, the subbrand represents a paradigm shift of everything from how cars are built, to what materials they use, to what kinds of impacts their construction has on the environment, to what kinds of tools they offer drivers." is something that I have been really impressed with. It is true. In the past two years, I've had the opportunity to talk and work with people at BMW that are working in the electric vehicle program and they are dead serious about a major paradigm shift in how they do business. I've written about this on various sites and usually get mocked pretty good,(laughed at actually) but I only know what I see and hear, and unless they are putting on some grand rouse, this is really the direction they see the industry going and they want to be leaders.
Also, your point #4 is definitely correct. They currently have at least 2 other electric cars in development, but chances are you won't hear about them for a couple years, or at least until these two are close to release.
I'm a bit surprised they went into detail about your #2 point. I didn't think they would talk much about this for a while, but I guess they wanted to introduce it and get people wondering about what it's all about. I'm thinking they just scratched the surface here on what i mobility is really going to do, but hey what do I know? :)

Funny, that picture of the i3 powertrain looks a lot like the one I posted on my blog six months ago:

· · 6 years ago

Lots of info, thanks!
I wonder about the range extender. I don't think a car engine could fit, and it would add a lot of weight in that light car. Maybe a motorbike engine, or something completely new.

· · 6 years ago


I tried to get the info out of them on REx, but I don't think they've fully made up their minds on the option yet and so weren't able to provide any specifics. I think it would make the most sense to have some kind of tiny (less than a liter) turbocharged engine that was optimized to run at consistent, high rpm and was tuned to be quiet at that rpm.


Thanks man! Yeah, those pics do look incredibly similar... you definitely have the inside line on BMW EVs :) I'm sure it's good to get some corroboration on how you feel about BMW's i program. What do you think about the 20-25 kWh battery claims?

· · 6 years ago

For me, the downside with a carbon fiber reinforced plastic body is that it figures to be difficult to recycle. Steel and aluminum are a lot easier to deal with when the vehicle is scrapped. I don't know that plastic cars are much of a leap forward when one considers life-cycle impacts.

Lighter weight vehicles help with efficiency a bit, but it pales in comparison to other design elements, such as Cd. And regenerative braking reduces the weight effect considerably compared to ICE cars, since much of the energy used to accelerate the mass of the vehicle can be recovered on slowing it down.

So, I don't get the fuss over carbon fiber plastic cars. Such materials make more sense for aircraft, where weight and strength are absolutely critical. IMHO, of course.

· · 6 years ago


It's true, the type of CFRP that BMW is using (Thermoset Resins, generally a liquid mixed with a catalyst under high temp which then causes it to harden) are notoriously difficult to recycle. BMW told me they have tried to weight the front end by having almost no waste from the molding of the plastic frame and the scant cuttings they do make are themselves recycled into non-critical CFRP applications. Barring a serious accident, CFRP frames should last longer than the rest of the vehicle which may mean they go to the scrap heap less frequently, but even so it is a problem. BMW did say that they have developed a pyrolysis procedure that can recycle thermoset resin CFRP, but that it's not yet cost effective or at a scale to be industrialized... although they do plan on doing more research into that method and think they will have quite some time to perfect it after the cars start hitting the market and it becomes needed.

Another option is CFRP based on thermoplastic resins. Thermoplastics can be melted out of the carbon fiber over and over and all materials can be reused. There aren't many companies that are using thermoplastic resins right now b/c they are more expensive, but prices are coming down. CFRP pioneers, Fiberforge are one of the only companies working on it.

· · 6 years ago

Thanks for all the information, Nick. I have a couple of questions: will the i3 rear doors remain as "suicide" doors? The Honda Element has a few issues because of these, and I would imagine that this would make side impact resistance much more difficult.

The REx sounds like it will be a true serial hybrid -- this would make it quite possible to just add it on as an option. Otherwise, they would have to add a multi-gear transmission and maybe a planetary gear type CVT like Prius et al. They probably would have to reduce the capacity of the battery pack, to fit in the genset?

I agree that aerodynamics are absolutely key to low energy consumption. The prototype Edison2 VLC (v3) electric managed to use just ~108Wh/mile at about 44MPH average on a 90 mile run. (Check their latest blog post.) The SIM-LEI prototype used ~134Wh/mile, and the Illuminati 7, the EV1 and Dave Cloud's Dolphin all have set marks at 150-165Wh/mile at highway speeds; and all have good to excellent aerodynamics.


· · 6 years ago

It is too bad that the i3 isn't front wheel drive, so that it can get more regenerative energy. The weight shift under deceleration means that the front wheels generate ~70% of the braking energy. This is a missed opportunity.


· · 6 years ago

Not just recylce problems, CFRP will make any body shop work expensive & a long wait. Someone had to wait a week just to get the bumper replaced on Leaf recently.

· · 6 years ago


I think it's pretty much set in stone that the production i3 will keep the coach style doors--aka suicide doors. REx is indeed a true serial hybrid. It's actually very unclear if they will have to reduce the battery pack size to fit it all in. My guess is yes, but it seemed like there was a lot of room in that rear area where the motor goes to add a small engine, small gas tank and genset. We'll find out soon enough.

· · 6 years ago


BMW doesn't seem to think that's the case. They think that body work will be simpler because there's no "banging it back into place." All it takes is cutting out a piece and glue-welding a new one back in. The glue-welding is done in a matter of minutes. It seems the longest wait would be for the new CFRP part if it wasn't in stock. Given that everybody overnights these things and they are so light, it probably wouldn't take that long. Also, the thermoplastic exterior panels are incredibly easy to fix--think Saturn. Likely the hardest thing to fix would be the aluminum crumple zones, but that would be on par with most modern vehicles. CFRP parts would likely be more expensive, but it might not cost as much in labor.

Why did it take a week to get a LEAF bumper fixed? It's not made of anything special, is it? It's certainly not CFRP, so I don't know how that relates to the BMW i3.

· · 6 years ago

I don't think they should reduce the battery size to go with the REx. It's not about cost, it's about the vehicle dynamics. The ICE would add weight at the very back of the car. If you reduce the battery, that would likely remove weight over the front wheels. That could make the i3 more fun to drive, but also more difficult to drive...

· Lad (not verified) · 6 years ago

Nice informative article; appreciate it. As many know BMW is very much about performance. Most of the cars that show up on track days are BMWs. So, I think part of their thinking about rear wheel drive is about driving a predictable car at speed and along with that idea come the balance of the car. By moving weight to the rear, the CG can more easily be moved to the center of the car. Also, I think the idea of rear wheel regen is somewhat desirable in that it can be adjusted to help stabilize the car on braking with a bit of grip drag. But, of course I'm thinking about how the car performs on a road track. All that lightness, electric power and aero makes me think that-a-way. But, I shouldn't because the car would be grossly limited by the amount of n-r-g it can store.

· Anonymous (not verified) · 6 years ago

A couple of years ago I saw a show about the car the Rocky Mountain Instuite build. They made a process to mass produce carbon fiber panels using a carbon fiber tape. Has this process not worked out as planned or what?

· · 6 years ago


The mastermind behind the RMI's CFRP work is Jon Fox-Rubin--who is now the CEO of FiberForge. FiberForge is one of the only companies working on making Thermoplastic CFRP affordable. Thermoplastic CFRP is, as I said above, the only CFRP that is easily recyclable. It also has the benefit of having incredibly low process times because it doesn't need any curing like Thermoset resin CFRP does.

See my article in Motor Trend for more info:

The main problem with Thermoplastic CFRP is that it is currently more expensive than Thermoset resins. FiberForge is working on developing new techniques that reduce that cost, but are still years away from bringing it down enough to put in cars. They mostly build components for the sporting goods industry.

· · 6 years ago

@Nick "Why did it take a week to get a LEAF bumper fixed? It's not made of anything special, is it? It's certainly not CFRP, so I don't know how that relates to the BMW i3."

I should have been more clear.

Brand new car with limited distribution apparently means difficult to get parts from Japan. The first part they got was damaged in shipping and they had to wait for one more. Connection to i3 is just in this difficult to get the park because of low volume & being brand new - and now we have to add another aspect, the newness of the process.

BTW, the glue-welding - is that something common that body shops can do ?

· · 6 years ago

"I don't think they should reduce the battery size to go with the REx. It's not about cost, it's about the vehicle dynamics."

I don't think they are going to Laurent. It was my understanding that it would go 100 miles AER and 100 miles in charge sustaining mode(stealing that phrase form the volt). It would have a very small gas tank (only a few gallons) so that's why it would only go 100 or so miles while the generator is on. Of course you could stop for gas and then keep on driving. The thought is that most i3 drivers won't use it as often as they may think they will, so why carry around a big gas tank and more gas than necessary. Look at the forums where volt owners post (I know BMW reads them) they are figuring out ways to drive without using almost any gas and the volt can only go 30-50 miles AER. The i3 will more than double the volts AER, so more people than not will rarely use the REx, even if they originally think they need it.

· · 6 years ago

@Tom "The i3 will more than double the volts AER, so more people than not will rarely use the REx, even if they originally think they need it."

Nice thing about i3 range extension is that - they are actually doing what Volt set out to do. An actual range extension instead of a complicated Frankenstein.

If we assume at freeway speeds, we can get about 70 to 80 miles on range extension, it means every hour on the freeway we have to stop and refill gas. So, the range extesion becomes a little less practical for longer drives but it does increase the range of the vehicle. I could easily go to Portland or Vancouver, but unlikely to take it on a trip to Yellow Stone.

· · 6 years ago


I don't read much Volt forums because I know first buyers were EV fanatics (nothing wrong with that, of course) who would do whatever they can to drive on electricity. I'm not sure the average driver would act the same. Also, as the i3 is a pure EV, it makes sense that the electric range isn't reduced because of an optional range extending system.

· · 6 years ago

The only other serial hybrid I know about is the FVT eVaro, that was in the X-Prize. It had an 1100cc 4-cylinder 20kW genset that could add about 350 miles of range with just a 2.2 gallon (US) gas tank. The electric range was about 125 miles on a 21kWh plugin pack. The ICE ran for about 1 hour to charge the battery (while driving at highway speeds) and then it shuts off. The ICE is run at it's optimum RPM and it drives a constant load.


· DRP (not verified) · 6 years ago

How will the recent purchase of the NiMH patent from Chevron/Cobasys/Ovonics by BASF affect the decisions BMW will make concerning the batteries that will be used in the i3 and i8? Since BASF is teamed with BMW, I would think it would be highly feasible to now produce high capacity NiMH batteries, which are less expensive, more stable, last longer, have an extended range, and are not difficult to recyclable, as opposed to lithium ion batteries, which cost more, are less stable, don't last as long, have less range, and are difficult and expensive to recycle. Mr. Stanford Ovshinsky admitted his mistake in selling his patent to GM, who sold it to Texaco/Chevron, who stopped the production of high capacity NiMH batteries in this country by controlling the patent. Now that a German company owns the patent will they produce the batteries for the Europeans only, or will Americans now have the chance to purchase Mr. Ovshinsky's battery, which he was directly quoted as saying in reference to the durability of his battery, "The wheels will fall off your car, before this battery goes dead". Before we get them in this country, gasoline will probably be $10 a gallon. I guess time will tell.

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