Carbon lightweight construction: BMW sees the automotive future in black

Menus

BMW sees black for the automotive future

Carbon lightweight construction: BMW sees the automotive future in black-construction

On the left, the weight test becomes hard work, on the right it becomes child’s play: a conventional steel beam and the same component made of carbon

Source: BMW / SystemĽTechnology, Research & DevelopmentĽ

If Bavaria has its way, cars will in future be largely made of carbon. The carbon fibers are spun in a community of 20,000 in the USA. Visit to the raw material factory of the future.

E.Few basketball players were born here, a handful of football heroes played their first games here, and PS gambler Evel Knievel was a citizen of this community for at least a few years. There is not much to say about Moses Lake.

But if BMW and the chemical company SGL have their way, the community of 20,000 people in Washington State will soon deserve a big flag, at least on the automotive world map. Because here in no man’s land, three hours east of Seattle, the two companies are working in a joint venture on the future of the car and are working on the material that will revolutionize vehicle construction: carbon.

The carbon fibers are considered the ideal material for body construction because they are extremely stable and yet light. The low weight especially recommends the carbon fiber for electric cars like the i3, wants to set off into the future with the BMW at the end of 2013. Because the lighter an electric car is, the fewer expensive batteries it needs to achieve an acceptable range.

Incidentally, more batteries not only increase the price, but also the weight. This is a vicious circle that cannot be broken with steel or aluminum. But with carbon you could turn back the weight screw, believes Jorg Pohlmann, who heads the joint venture in Moses Lake. If only the hair-fine threads weren’t so expensive for their part that Pohlmann reverently speaks of "black gold".

Because BMW still wants to go into large-scale production with it, the engineers have developed a new production chain that is intended to dramatically shorten process times and cut costs. And the most important link in this chain is Moses Lake. So there is a kind of gold rush atmosphere there.

Here the still white and very fragile raw fibers, which come as bushy endless strands from another BMW joint venture in Japan, are first oxidized and then literally grilled before they are spun into bundles of 50,000 fibers each and wound on those spools which they knit special carbon mats in the Bavarian town of Wackersdorf.

Hardly any manpower required

These mats are then layered in several layers at the BMW plant in Landshut, cut and soaked with special resins so that the body parts from which the i3 will be assembled in Leipzig in the future can be produced under pressure in huge ovens.

The first trial in Moses Lake hardly needs any manpower. Plant manager Steve Swanson only assigns six men per shift to check on the largely automated machines. "We don’t have 50 employees for three-shift operation 365 days a year," says the plant manager.

But in addition to the right tension for the endless fiber strands and a few more or less secret ingredients, he needs one thing above all: extremely high temperatures. The ovens through which BMW pulls the strings have up to 1400 degrees Celsius until they are more resistant than steel and lighter than aluminum.

Green electricity for the carbon bakery

These ovens, each as big as a railroad car and as heavy as a family home, are the real reason why the carbon fibers are baked in Moses Lake, of all places. Because BMW has to cover the immense energy requirements for the carbon bakery with green electricity if the electric cars are to meet the standards. And everywhere else in the world it is either too scarce or too expensive. "In Moses Lake we get green electricity at unbeatable rates," says joint venture boss Pohlmann.

Because the municipality is involved in two huge dams on the Columbia River and produces more hydropower than the 20,000 inhabitants can use, they sell the kilowatt-hour to BMW for as much as three US cents. When it comes to further processing in Wackersdorf, however, the car manufacturer pays 15 euro cents for the green electricity. "If you then consider that the lion’s share of the total energy requirement in carbon production is initially incurred, the decision on the location is easy to explain," says Pohlmann.

High costs, small quantities

Japan, USA, Bavaria, Saxony – Pohlmann accepts that the raw materials for the body of electric cars will travel halfway around the world before the car even drives the first meter. “The material is literally easy to transport,” says the BMW manager. That is why the entire logistics process only accounts for one percent of the energy required in production.

Production in Moses Lake has been going on for a few months, and in Wackersdorf they are busy knitting the carbon mats from which they then bake the finished components in Landshut. And construction of the first pre-series models will soon begin in Leipzig. Technically, BMW obviously has the future under control. But that’s only one side of the problem.

The other is the cost. Because until now, carbon bodies have been priceless and reserved for super sports cars such as the Bugatti Veyron, the Lamborghini Aventador or the McLaren 12C. High prices, small quantities – that was the rule when dealing with carbon fiber up to now. The few thousand roof elements that BMW has already baked for the M3 as a kind of finger exercise for the i-age are a notable exception.

30 components for the cell of the i3

But with the i3, BMW wants to go beyond the previous framework in both directions: Management thinks in terms of quantities that are no longer three-digit, but rather five-digit. And we are not talking about a vehicle price of several hundred thousand euros, but of just over 40,000 euros – including the batteries for the electric drive.

If you are honest, the targeted 40,000 euros for a 3.85 meter long small car is a very self-confident announcement (especially since you would get a BMW 520i for this money), but despite all the efforts, the carbon fiber technology is "still damn expensive" as Jorg Pohlmann also admits. However, there are also a few cost advantages: The carbon parts of the i3 are larger and therefore less complex than in conventional cars.

Instead of using 800 robots to weld 350 elements into a body with 800 robots, for example, 30 components will be glued together in Leipzig until the cell of the i3 is finished. And instead of the mighty IG Metall, BMW is dealing with the textile union in the carbon world and is happy about more convenient collective bargaining partners, longer working hours and lower wages.

The future looks black

Joint venture boss Pohlmann believes that in less than ten years he will be able to bring the price of carbon down to the level of aluminum, above all by increasing the mass. They are currently building a second production line in Moses Lake. "Then we have an annual capacity of 3,000 tons here," says Plant Manager Swanson. That is almost ten percent of the current world carbon production, and that means that the area is not exhausted.

“On our total of 60 hectares, we still have space for ten additional production lines, each with 1,500 tons. And on the other side of the road there are another 70 hectares reserved. ”So Swanson sees the future of the car as black, which is a sign of optimism given the color of the finished carbon parts. The prerequisite for this, however, is a good start to the 40,000-euro i3.

The journey to carbon manufacturing was supported by BMW. You can find our standards of transparency and journalistic independence at www.axelspringer.de/unabhaengigkeit

Related articles

Please follow and like us:

Leave a Comment