Mercedes’ AMG brand has unveiled a concept car that is a VIN-ready rocket ship of an EV. Three axial-flux motors combine for 1,340 horsepower (985.5 kW) for a top speed of 220 mph (354 km/h).
The new axial-flux motors are designed to be smaller, lighter, and provide more efficient power output when compared to conventional motors. Most electric vehicles use a radial flux design, in which a tubular stator spins inside a hollow tubular housing perpendicular to the motor shaft. AMG’s axial flux motors instead have a disc-shaped stator that spins parallel to the shaft. This creates a motor that is 67% lighter and smaller than a conventional design with a similar output. That means three times the power density and double the torque density.
Powering those axial flux motors is a new battery design using oil-cooled, tall, cylindrical cells of NCMA chemistry. The nickel cobalt manganese aluminum oxide cathode for the lithium-ion battery adds aluminum to the standard nickel cobalt manganese cathode found in many advanced battery designs. This increases capacity and energy density as well as power output for the cells. All while reducing cobalt content and improving structural stability.
The 800+ volt battery pack in the Concept GT XX contains over 3,000 of these NCMA cells, giving it the capability of 850-kW fast charging. Mercedes did not specify the total size of the pack, but did say the energy density is 300 Wh/kg.
The motors the pack powers are packaged in an interesting way. They're housed within an electric drive unit (EDU) with a planetary transmission and silicon carbide inverter. The rear unit holds two motors and outputs 860 horsepower (632.5 kW), while the front unit houses one motor, a spur-gear transmission, and the rest of the output.
Aerodynamics are also a large part of the Concept GT XX’s design. Its drag coefficient is a mere 0.198, thanks to body aero design and active-aero wheels. The blades on the wheels are “cloaking,” meaning they move to open or close the wheel’s interior for brake cooling or aerodynamics as needed.
The overall body shape is short, fast, and powerfully nostalgic, with the grille and hood portion looking very much like a classic 300 SLR.
A V8 soundtrack through headlight-embedded speakers, yoke-style steering wheel, carbon-fiber accents and seating, and illuminated orange accents all create the mood for the Concept GT XX. The video-game-like interior and programmable center tail light (between standard tail lamps) complete the low-slung design of the concept.
Mercedes has made it clear that this concept is road-ready and will see production. I'd expect most of the next-level and video-gamey parts of it to disappear in the concept to production process. But the core of it, especially the technology of the drivetrain and aerodynamics, are real-world ready. Assuming they can pass rigorous durability testing.
Source: Mercedes-AMG
