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VW, BMW, JLR differ on best choice for EV architecture efficiency

Release Date:2020-04-26

VW Group has invested $7 billion in the MEB platform so it can build EVs of all sizes using many of the same parts so it can make its e-models profitable.

Electric cars need to be constructed differently from combustion-engine cars. Ulf Sudowe, r&d director for chassis at Gestamp, gives the example of the time the Spanish auto supplier test-fitted an electric motor to the subframe of a standard Volkswagen Up minicar. "Everything was destroyed," he said. The ramp-up of torque for an electric motor happens so fast, Sudowe explained, that a standard subframe can't cope.

For the electric e-Up, Gestamp developed a unique subframe. The difference between the two means that new stamping dies were needed to create the new subframe, increasing the costs and complexity of producing the electric version.

It's this kind of complexity that Volkswagen Group has worked hard to avoid when creating its Modular Electric Toolkit, commonly known as MEB. The $7 billion investment is expected to allow VW Group to build everything from compact cars to large minivans using many of the same parts, providing the crucial economies of scale that the company says will enable it to make EVs profitably.

VW will build MEB cars in eight locations globally starting in 2022 and predicts it will sell 15 million vehicles on the platform in the next decade. But what if it doesn't? "If the EV demand isn't there, Wolfsburg is going to have a big, big problem," Max Warburton, an analyst at Bernstein bank, wrote in a July report.

Other manufacturers have the same fears. "If we predict the success of the 3 series, we are pretty much spot on," Oliver Zipse, the new CEO of BMW Group, said just before his appointment in July. "Predicting electromobility is much more difficult."

This is not 2030

BMW, along with manufacturers such as Jaguar Land Rover and PSA Group, have rejected VW's solution of a stand-alone platform. Instead, they are creating flexible platforms that encompass both combustion and electric drivetrains. "In 2030, we might have a different approach," Zipse said. "But we are not living in 2030, and we believe very firmly this is the right answer to keep the company afloat and profitable."

By keeping platforms flexible, BMW can raise or lower production of a particular drivetrain according to demand, Zipse said. Plants can be easily adapted. "To integrate different drivetrains in one plant without losing efficiency, that's the secret," he said. "Either you can do that or you cannot. And we can do it."

Customers won't care, Zipse said. "You will not feel any difference between a single-purpose platform, a conversion platform or a flexible architecture, maybe 2 kilograms here or there. But it's not relevant for a buying decision."

Not everyone agrees. "In an ideal world, you would do everything on a bespoke platform," said Tim Urquhart, principal automotive analyst at IHS Markit. "The whole point of an EV platform is that it doesn't have to be too complex. You have the skateboard platform and have a blank canvas. It will afford you many more advantages."

Simplifications to an EV platform might include dropping the brake calipers and drums on the rear axle because brake regeneration means they're no longer needed, said Patricio Barbale, senior chassis analyst at IHS. Or using the electric power to introduce more energy-hungry electric systems such as steer-by-wire, which then save space.

With the MEB platform, VW has switched to rear-wheel drive on the simpler versions, whereas others will be four-wheel drive, which means the instant power delivered won't corrupt the steering. VW also makes a big deal of the fact that the cabin will be larger because it can push it farther forward without the need to package an internal-combustion engine up front.
"The length of a Golf, the room of a Passat" is how VW describes the first car on the MEB platform -- the ID3, which goes on sale next year.

The fossil age

An automaker that builds on a unique platform can market the car quite differently from a similar-size combustion-engine model. That will be important given that -- for a few years yet, anyway -- the expense of the battery pack will price the electric car higher. VW is already doing this.

"The Modular Electric Toolkit jettisons all the ballast of the fossil age," VW declared in its marketing, adding that MEB led to "fundamental" changes for everything from body design to interior packaging. We'll know if it has been successful when VW shows the ID3, likely this month at the Frankfurt auto show.

Meanwhile, an electric car on a flexible platform could end any unfavorable comparisons to its cheaper combustion-engine version. Within the VW Group, Audi and Porsche are developing a larger platform for premium cars: PPE, or Premium Platform Electric.

But VW isn't the only one investing in pure electric platforms. Daimler is working on the Electric Vehicle Architecture -- or EVA2 -- expected in 2021. Two sedans and two SUVs are expected to be the first to use it.

Meanwhile, Renault Nissan is developing the CMA -- an electric-only, flat-floor version of its broader Common Module Family architecture -- expected in 2022. And in Japan, Toyota is working with Subaru on an EV platform it announced in June. No timing has been given.

The EV-only platform design with the batteries sandwiched in the floor does present its own problems. In cars where the size of the battery box pushes it toward the edges, the car needs more crash protection.

"In the side impact you have a very limited zone of deformation to the battery -- about half," said Niclas Brannberg, director of computer-aided engineering for the Chinese electric-car brand Nio. That means extra stiffness, meaning more expensive extruded aluminum beams for Nio.

But Brannberg, who has previously worked for Volvo and Saab, estimates that the cost of developing a new electric-only platform is similar to that of a pure combustion-engine platform.

VW is way ahead on cost with MEB, said Sudowe of Gestamp, which builds battery boxes and chassis parts for cars using that platform. "MEB will be the benchmark for everyone," he said. "It's very good on the price perspective."

For example, all MEB models except the minivan will use the same control arms, saving money on dies. Sudowe estimates that MEB is around half the cost of the EV-only platform Jaguar Land Rover developed for the Jaguar I-Pace.

The I-Pace platform, designed as a halo car to beat Jaguar's premium rivals to market, is not expected to be further developed. Instead JLR will migrate models to its new flexible Modular Longitudinal Architecture starting next year. The first model to use it will be an electric version of the XJ large sedan.

Suppliers are being asked to be more flexible with EV-specific parts, just in case the actual numbers needed are lower than quoted -- or higher. "Today, probably none of our customers are absolutely sure how fast the market is going to move to EVs," Gestamp Chairman Francisco Riberas told Automotive News Europe. VW recently doubled its order of battery boxes for MEB cars from Gestamp to 570,000 a year. The order indicates greater confidence that customers will switch to EVs as European laws tighten on carbon dioxide emissions starting in 2020.

VW's confidence is partly because it has the scale -- even more so now that Ford has agreed to use MEB for a range of European electric cars. For those without the brand reach to spread the investment, a flexible platform makes more sense.

"They want to minimize the risk," he said. "Even if maybe a platform is not the best for EVs, they adapt it so they have a bit more flexibility in terms of volumes. It might not be the best solution, but it will probably be the most intelligent."

source: https://europe.autonews.com/automakers/vw-bmw-jlr-differ-best-choice-ev-architecture-efficiency

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