On Thursday night, Cadillac unveiled a new SUV, the Lyriq. It’s the brand’s first battery electric vehicle, and the first vehicle to use General Motors’ new BEV3 platform and Ultium battery technology, which is set to spawn 22 new BEVs across the company’s range of brands between now and 2023. Cadillac isn’t spilling all the beans about the Lyriq just yet, but it did share some info with Ars ahead of the livestream launch. The headline figures are a range of “beyond 300 miles” (482km) on a single charge, DC fast charging at “over 150kW”, and the fact that it will come in rear- and all-wheel drive configurations.

Additionally, it’s going to feature a massive 33-inch display on the dashboard that combines the main instrument panel and the infotainment system, a dual-plane augmented reality heads-up display (that features information like vehicle speed on a close plane, and navigation directions on a far plane), and advanced driver assistance systems including the latest version of Super Cruise and the ability to remotely park itself.

Recently, I spoke with Michael Harpster, global chief engineer for electric and hybrid propulsion systems at GM, to find out a bit more about the new BEV3 platform and the lessons that GM has learned from its previous vehicles like the EV1 and Chevrolet Bolt EV. “We were doing the math, and you know, we’ve got 25 years of production EV experience, going back to the EV1. So, there’s a huge history of General Motors and electric vehicles,” he told me, adding that his team at GM still includes a couple of engineers who worked directly on the EV1, which was in production between 1996 and 1999.

That car is probably less relevant to the Lyriq than the Bolt, however, and I was curious what lessons Harpster and his team had learned from it as they developed this third-generation electric platform. “The Bolt is a smaller car, and it’s a 60kWh pack which at the time was a big pack. But with the Ultium system we wanted to get up to 100kWh for the Lyriq. And that really made us think about the integration of the propulsion system into the vehicle in a much deeper way. It’s not just shoving that much energy into a car, it’s really about thinking about what the customer wants, and they want the height of that pack to be as small as possible, right? They want a very thin pack to maximize interior volume,” he said.

At the same time, the Lyriq’s design team had their own demands for more styling flexibility. “Unlike the Bolt where there’s a double deck [of cells] under the rear seat, we made it as flat as possible, and extended it out to the rockers. So, we did that by taking some of the elements of what we did in the Bolt but pushing it even further where the battery pack enclosure is a structural element of the car—it’s the backbone of the car. And it’s highly integrated into design structurally, particularly with the rocker and the side of the pack—those two work as a co-design,” he explained.

Shhh, you’re making too much noise

Obviously, a Cadillac needs to have a different character to some of GM’s other brands. “So unique to Cadillac—certainly NVH [noise, vibration, and harshness]. You look at the expectation on the sound quality, on the magnitude of the sound of the vehicle’s propulsion system; there’s been a lot of focus on that. Learning from the Bolt, you get into motor design and EVs, and there are certain noises that come along and you struggle with them. Every generation, we get smarter on how to address that in our motor design” Harpster told me.

Perhaps predictably, performance was also another key aspect. “unlike the Bolt, where it was a single drive unit on the front axle, so it was just a front wheel drive car, the Lyric is rear-wheel drive and again that was a Cadillac-driven feature.—the move from a front axle drive to a predominant rear axle, so that the biggest power is on the rear axle to give it the characteristic of a rear-wheel drive car. In particular, when we go to performance all-wheel drive, we put another drive unit on the front axle,” he said, although added that the AWD version of the Lyriq is still dominantly driven by the rear motor-generator unit.

The front and rear MGUs aren’t identical, but “they are designed as a family. So, they do have attributes that are similar, but the power is quite a bit different. So the power of the rear axle is is higher,” he explained. While he wouldn’t give too much away about the new BEV3 motor family design, Harpster did say that they’re designed to be more efficient and quieter than the MGU in the Bolt EV, and that they use fewer rare earth elements. “It’s really the trick of getting capability out of the motors, without, spending money on the crazy expensive magnets that use some of the heavier rare earth materials, so we’ve been pretty aggressive in that,” he told me. Additionally, the family of motors has been designed to be easier to manufacture, with common fixture points even though the front and rear MGUs might not look that similar from the outside.

Constant iteration

Still, it hasn’t been all plain sailing. “We redesigned the front drive unit—the physical orientation of it—three times, really working with the vehicle team trying to find the optimal configuration to give Design the styling flexibility they wanted, to optimize crash [performance], and fit it in the car. Just getting that much battery into the car in an efficient package—we spent a lot of time on that really thinking structurally about the vehicle and how you keep a load coming from the front crossmembers or the front mid-rails down into the rockers and how to manage that load transition while keeping the passenger foot wells and interior space to be what you want it to be—that was a challenge,” Harpster said.

Keeping the battery pack happy was also a priority. “As you go to higher energy densities there are issues that come along with that in managing the cells; they need a lot of care and feeding. So, a lot of energy was put into making sure that these high nickel cells are being treated the way they want to be treated,” he said.

Harpster is particularly proud of the way the power electronics have been integrated. “on the rear drive unit of the Lyriq, we have the inverter packaged within the drive unit. On the front right drive unit we have not only the inverter but the power electronics, the DC-DC (12V to high voltage converter), the onboard charger’s in there, and some other components; that was a big win for the program. If you look at the amount of content that we put into those boxes, it’s really pretty outstanding compared to what the industry norms are. The physical size and capability of those packages is really industry leading,” he told me.

The Lyriq will go on sale for model year 2023 (which means calendar year 2022). Pricing will be announced closer to the time, but we expect the range to start at around $75,000.

Listing image by Cadillac

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