Forget the looks, love the tech: The $83,200 BMW iX electric SUV

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A white BMW iX
Enlarge / The $83,500 BMW iX is the brand’s new technology flagship. It’s a battery electric SUV with a range of more than 300 miles.
Jonathan Gitlin

MUNICH—Regular readers of Ars will know that we make no bones about our love for the BMW i3. BMW’s third-generation electric car taught the automaker plenty about EV powertrains as well as more sustainable manufacturing. But the i3 has taught BMW all it could, and now the time has come to apply those lessons to more mainstream EVs. And nothing is more mainstream these days than an SUV, so BMW has developed an all-new one to showcase the company’s fifth-generation electric powertrain.

Enter the 2022 BMW iX.

Trickle-down might be a myth in economics, but the principle does work in the auto industry. Car makers develop new technology and launch it in their high-end vehicles first before economies of scale see such features show up in cheaper models. This is particularly true of the German luxury brands like BMW, which in the past used its 7 Series flagship sedan as its standard-bearer, introducing things like the first true infotainment system. But big sedan have fallen out of favor with the people who buy big luxury cars, and so the time has come for the flagship SUV instead.

The iX’s body is a space frame of aluminum, reinforced with high-strength steel and carbon-fiber composites in the roof frame and the A and B pillars. More visibly, BMW has used carbon fiber for the side frame, cowl panel, and rear hatch frame; the material saves weight versus more conventional plastics as well as adding a little extra structural strength. The result is a curb weight of 5,534 lbs (2,510 kg), which is in the same ballpark as the V8-powered X7.

The iX is a little smaller on the outside than an X7: 195 inches (4,953 mm) long, 77.4 inches (1,967 mm) wide, 66.7 inches (1,695 mm) tall, and with a 118.1-inch (3,000 mm) wheelbase. But the superior packaging of a battery electric vehicle means the iX’s interior is comparable in size to the X7’s.

The powertrain is arranged exactly the way you expect: an electric drive unit for each axle, and in-between, the car’s lithium-ion battery pack. BMW says that the lessons it has learned with previous generations of electric motors means that the new drive unit—which integrates the motor, single-speed transmission, and inverter—has a 40 percent greater power density than before.

The motor uses copper hairpins for the stator, and it’s an electrically excited synchronous motor (rather than a permanent magnet synchronous motor). BMW says that using electricity instead of a magnet means it has much finer control over the magnetic field. As a result, the motor can provide a very steep torque curve but can also reduce the magnetic field when the motor isn’t needed, increasing overall powertrain efficiency. Not using permanent magnets also helps BMW with its effort to consider the environment with regards to its supply chain.

$83,200 before tax credits or the options list

The drive units can be specced with different outputs, but at launch we’re just getting a single configuration of the iX for model-year 2022: the $83,200 iX xDrive50 (before the $7,500 IRS tax credit). The front drive unit is rated at a peak output of 268 hp (200 kW) and 260 lb-ft (352 Nm); the rear peaks at 335 hp (250 kW) and 295 lb-ft (400 Nm). However, the combined output is also affected by how much power the battery can send to both motors simultaneously—in this case, 516 hp (385 kW) and 564 lb-ft (765 Nm).

The high-voltage battery pack has made similar gains in terms of increased energy density—about 40 percent compared to the battery in the outgoing i3. BMW sources the prismatic cells from CATL and Samsung SDI, but the rest is done in-house in a new battery facility at its Dingolfing factory. The iX xDrive50 uses a 106.3 kWh pack (useable; gross capacity is 111.5 kWh) comprising six modules of 50 cells each and another five modules each with 40 cells.

That should be sufficient for an EPA range of 300 miles (482 km), although the official EPA rating will be announced closer to the car’s arrival in the US market in the first quarter of 2022. The WLTP range, which rarely has any relevance to real-world driving (in the US at least), rates the iX xDrive50 at 391 miles (630 km).

I’m optimistic that BMW’s 300-mile estimate is correct, however. Since leaving the factory 1,235 miles (1,987 km) ago, the iX I was testing averaged 2.8 miles/kWh (22.1 kWh/100 km), which includes time running flat-out on derestricted German Autobahns at 124 mph (200 km/h).

My seat time in the iX was a little over four hours, or 160 miles (259 km), and I averaged 2.5 miles/kWh (24.6 kWh/100 km). That includes, however, driving up into the mountains but not back again, where gravity offers a helping hand and lets you regenerate energy as you descend.

When it is time to charge, the iX can DC fast-charge at up to 195 kW, taking 40 minutes or less to charge from 10 percent to 80 percent. AC charging maxes out at 11 kW on single-phase electricity, and charging from 0 percent to 100 percent in this manner should take 11 hours in total.

It’s still a driver’s car

You can’t call a car your new technology flagship without giving it some clever technology, and since BMW has always prided itself on making cars for people who enjoy driving, using technology to augment and improve the driving experience is something BMW has focused on.

The iX has three drive modes: Efficient, Sport, and Personal (which lets you select your own combination of steering, suspension, throttle response, regenerative braking, interior lighting, and so on). Efficient is, as you might expect, the most efficient mode—the throttle map reduces the amount of initial tip-in and readily decouples the drive units to allow the iX to coast at speed if the drive selector is in D. There’s also true one-pedal driving, for those who prefer their BEVs that way—simply use the drive selector to put the car into B rather than D.

Despite the iX’s mass, it responds to direction changes quickly—the electric motors that drive the wheels and assist the steering counteract the excess kilograms, and the optional air suspension does a highly effective job at controlling the ride.

The iX is not quite as plush as the Rolls-Royce Ghost we tested earlier this year (which also starts life in Dingolfing before being shipped to the UK for final assembly). But it’s close, which is impressive for a car that costs a fifth as much. Like the Rolls-Royce, it might be at its most enjoyable on a flowing country road when you’re trying to conserve momentum. Keep it in D, and then just add enough energy here and there as necessary, gliding along in near silence.

But the iX is still a BMW. For spirited driving on a twisty road—a thing that’s still core to the brand—the combination of Sport mode and B works very well. Under these conditions, you only need to use the brake pedal (which blends regenerative and friction braking) if you’re having to brake heavily; for braking at about 0.3 G or less, lifting your foot off the throttle is all that’s required. The travel is long enough that it’s easy to modulate that lift-off braking even after just a few minutes in the iX. However, even though the steering gets heavier in Sport, it doesn’t really gain any extra feel.

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