The Mercedes-Benz CLA Will Be A Range And Efficiency Monster With EQXX Tech

Almost three years ago now, Mercedes-Benz showed off something that seemed capable of doing the impossible. Dubbed the Vision EQXX, it had the same size battery as a Mercedes EQS, just 30% lighter and taking up half as much space. Its electric motor was much smaller than most with its power output. It was aerodynamic enough to make a fighter jet look like a school bus.

Put all those innovations together, and Mercedes had a car that could drive 747 miles on a single charge—yes, really—or 627 miles in the heat of a Saudi Arabian desert. And it delivered groundbreaking electric efficiency of up to 8.5 miles per kilowatt-hour, almost twice as good as today’s best EVs.

At other automakers, this project would have stayed a mere science experiment. Not so at Mercedes-Benz, where one of its top engineers recently told me the car’s technology will directly translate to its most important EV yet: the new CLA-Class.

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Timo Stegmaier, Mercedes head of e-drive compact/midsize and system validation, also worked on Mercedes-Benz’s groundbreaking EQXX project and has been responsible for bringing many of the learnings from there into the almost production-ready CLA. 

“The world-record EQXX, it was very important for us with the car to influence series production,” Stegmaier said of the long-tailed prototype machine. “It was really nice not only doing a showcase with the EQXX, it was pretty cool also here in the CLA.” 

The new CLA-Class will be a crucial model for Mercedes-Benz. Its first go at EVs, the EQ-branded sedans and SUVs, didn’t really make a splash in the marketplace as expected. Future Mercedes electric models are now said to look much more like their familiar gas-powered counterparts. And like other automakers, Mercedes is also pushing back its all-electric goals as sales prove uneven.

But it can’t give up on EVs entirely. Mercedes faces intense electric competition in, and now from, China. It has strict emissions and fuel economy standards to meet globally. And the company long known for innovation doesn’t want to cede that leadership to anyone. So the CLA-Class will be the first of several new more compact, ultra-efficient electric sedans, wagons and even large crossovers. And they’ll have hybrid versions featuring batteries paired with a new high-efficiency four-cylinder engine. 

Any way you look at it, efficiency is the name of the game here. The EQXX set new records for that on multiple occasions. Much of the technology from EQXX will live on in the CLA in some form or another, but Stegmaier said there have been some improvements, too. 

“The CLA has a similar motor” to the EQXX, he said, improvements over the powertrain seen in the EQE and EQS covering not only hardware design but softer stuff, like the types of lubricants used within. Stegmaier declined to elaborate on that but said that the fundamental concept of the battery and its electronics, that of “the one box,” continues on from the EQXX as well.

With this design, Mercedes engineers placed not only the battery cells and thermal management but much of the charging and controller infrastructure together into a single component. This will surely simplify manufacturing but also optimize space within the Mercedes Modular Architecture, or MMA, the platform that the CLA will roll upon.

It also creates room for a frunk, which previous models like the EQE and EQS have lacked. “It is a very compact motor out in the front,” Stegmaier said. “So the compact design makes it possible to have a really quite cool frunk.” Stegmaier wouldn’t give me a specific volume, but by the sound of things, a few groceries or a backpack would be reasonable.

But there’ll be other improvements, too, including an energy density from the 85 kWh nickel-cobalt-manganese (NCM) pack that, Stegmaier says, is 20% higher than the company’s previous cells.

The drivetrain configuration is substantially different from the EQ cars, too. While the front motor arrangement is similar, a permanently excited motor with a disconnect, the rear of the CLA relies on a two-speed transmission. 

Stegmaier called this system: “The heart of efficiency.” Two speeds enable the rear motor to operate efficiently at a greater range of speeds. 

Knowing that EV transmissions are a controversial topic—especially whether the additional complexity is worthwhile—I asked whether there was any internal debate about going with this approach for the CLA. “It’s not an easy decision because, as you said, it’s also complex and costly,” he said. “But we were very clear. We also want to bring that efficiency into the CLA, and there, the two-speed gearbox is absolutely necessary.”

The result is a car that, Stegmaier says, will cover a whopping 5.2 miles per kWh and deliver 93% efficiency. That should trump even the Lucid Air Pure as the most efficient EV around. This performance, he said, actually hampered his team’s earlier testing in the Alps.

“There were many times my team was coming up to me and saying, ‘We had a problem. We couldn’t do any charging tests because we couldn’t get the car empty,'” he said. 

PR-friendly testing problems aside, part of that efficiency in steep terrain is thanks to significantly higher regen rates than previous Mercedes-Benz EVs. The CLA is able to generate up to 200 kW under braking, or almost three times what a Tesla Model 3 can do. Stegmaier declined to say how many Gs the car can sustain under deceleration but did say that the most aggressive of the three regen modes (D, D-, and D+) will be a proper one-pedal experience, with the car coming to a complete stop. 

That captured momentum will, of course, help recharge the battery via the car’s 800-volt system. When it comes to charging the old-fashioned way, a 320 kW DC charger will enable grabbing 186 miles of charge in just 10 minutes, part of what helped the team cover over 2,300 miles in 24 hours in yet another record-breaking run. 

That charging will happen via a Tesla-style NACS plug, while a separate J1772 plug is there for slower duties. And, Stegmaier assured me that the power will flow both ways: “We will offer bidirectional charging, so you can use the CLA also as storage,” he said.

That’s a lot of good news for EV owners, but the changes extend beyond the hardware of the new platform. The CLA will display significant software revisions as well, starting with the MB.OS system running in the dashboard.

The software controlling those motors is also improved, something Stegmaier said would be a boon in low-grip conditions, such as the slippery, snowy test ride I got. Even in deep snow, the CLA’s dual-motor all-wheel-drive system didn’t skip a beat. 

Again, much of this is thanks to the learnings from the electric EQXX, but many were surprised to learn that the platform it spawned, MMA, will also be used for a 48-volt hybrid.

Mercedes has confirmed they will release an internal combustion version of the CLA, and while that news dropped only recently, Stegmaier said a hybrid was always part of the plan: “It was from the beginning,” he said, “because we want to offer both worlds, both customer needs. So if you go to the shop, you will buy a CLA. The second question will be, which powertrain do you want to choose?”

That, then, raises the question of how these two CLAs will be differentiated in the market. Both will simply be called CLA, with Mercedes-Benz relying on its numerical nomenclature to identify the powertrains, much like with the current G-Class. There, the internal combustion models are G550 or AMG G63, while the electric model is the G580. 

I asked Stegmaier if there would be any significant visual differentiators. “There are little, very little, differences between the hybrid and the electric car,” he said, suggesting the grille treatment will be the biggest differentiator. 

That means you’ll be able to see more than a little of the design heritage of the ultra-efficient EQXX EV even in the gas-powered CLA. But where that car featured a dramatic but somewhat impractical shape, with a long tail designed to help aerodynamics, the CLA’s shape will be more pert, more practical.

And, if the CLA Concept is any indication, something far more attractive than Mercedes’ current EV offerings. 

Tim Stevens is a veteran editor, analyst, and expert in the tech and automotive industries. He helmed CNET’s automotive coverage for nine years and acted as Vice President of Content. Prior to that, Tim served as Editor-in-Chief at Engadget and even led a previous life as an Enterprise Software Architect. Follow Tim on Twitter at @tim_stevens and catch his Substack.