The "Pancake" Revolution: Mercedes-Benz Launches Serial Production of High-Performance Axial Flux Motors in Berlin

In a milestone development for automotive engineering, Mercedes-Benz has officially inaugurated the mass production of its proprietary axial flux electric motors at the historic Berlin-Marienfelde plant. This transition marks more than just a new assembly line; it signals the birth of a new era in electric propulsion, where the traditional "V8 of the electric age" replaces conventional radial motors with a compact, ultra-powerful architecture that promises to redefine the performance standards of electric vehicles (EVs).

Main Facts: The Power of the "Pancake"

The axial flux motor, colloquially dubbed the "pancake" motor due to its flat, disk-like shape, represents a radical departure from the cylindrical radial flux motors that have dominated the EV market for over a decade. In a radial motor, the magnetic flux runs perpendicular to the shaft; in the axial flux design, the flux runs parallel to the axis of rotation.

This configuration allows for an unprecedented power-to-weight ratio. Mercedes-Benz reports that these units occupy less than one-third of the space required by conventional motors while providing a three-fold increase in power density. The primary architectural difference is the "sandwich" construction: two rotors encase a single stator. This design not only minimizes the motor’s footprint—measuring roughly 8 to 9 centimeters in width—but also enables the integration of the motor into a "High Performance Electric Drive Unit" (HP.EDU) alongside a compact, single-stage planetary gear system.

The first vehicle to feature this cutting-edge technology in series production is the new Mercedes-AMG GT 4-Door Coupé. By bringing this production to the Berlin-Marienfelde plant—a facility that has been part of the Daimler story since 1902—Mercedes is effectively transforming a legacy combustion engine site into a global competence center for next-generation electric propulsion.

Chronology: From Concept to Industrialization

The journey to the assembly line in Berlin began long before the ribbon-cutting ceremony attended by German Transport Minister Patrick Schnieder.

• 2021: Strategic Acquisition: Mercedes-Benz acquired Yasa, a British electric motor specialist and pioneer in axial flux technology. This acquisition was the catalyst that moved the technology from a laboratory prototype to a scalable industrial product.
• 2022–2023: Testing and Validation: The technology underwent extreme stress testing via the "Concept AMG GT XX." During these trials in Nardò, Italy, the motor demonstrated its durability by running for over 40,000 kilometers in just seven days, setting 25 long-distance records.
• 2024–2025: Industrial Scaling: Mercedes invested heavily in the Berlin plant to adapt the facility for the specific, highly complex manufacturing requirements of axial flux motors.
• 2026: Serial Production Launch: With the arrival of the AMG GT 4-Door Coupé, the technology reaches the showroom floor, marking the successful industrialization of a design once thought to be too complex for mass production.

Supporting Data: Why Axial Flux?

The performance metrics provided by Mercedes-Benz highlight why this transition is critical for the future of the AMG brand. The technical advantages can be broken down into three pillars:

1. Thermal Management

One of the primary failure points in traditional radial motors is the difficulty of dissipating heat from the copper windings. As Jörg Miska, CEO of Yasa, explains, heat accumulation in traditional motors leads to performance degradation—essentially "energy evaporation." The axial flux motor utilizes a direct-cooling approach, where a non-conductive fluid flows directly over the copper coils. This allows the motor to maintain peak performance even under the extreme stress of repeated, high-speed track launches.

2. Geometric Efficiency

The "pancake" architecture is significantly more compact. By utilizing rectangular copper wire in the stator rather than traditional round wire, engineers can pack more conductive material into the same volume, increasing electromagnetic efficiency. The motor is capable of reaching rotational speeds exceeding 15,000 RPM, yet it remains slim enough to be integrated into tight chassis spaces without compromising cabin or trunk volume.

3. Record-Breaking Performance

The real-world validation of these metrics is seen in the AMG GT 4-Door Coupé:

• 0–100 km/h acceleration: 2.1 seconds.
• Top speed: 300 km/h (with Driver’s Package).
• Endurance: During the Nardò trials, the motors operated in ambient temperatures of 35°C+ while maintaining consistent 300 km/h speeds, supported by ultra-fast 850 kW charging intervals.

Official Responses and Strategic Vision

The shift to Berlin-Marienfelde is a strategic move for the Mercedes-Benz Group. Michael Schiebe, former AMG chief and current member of the board, has emphasized that this technology is not merely for show—it is a performance-critical asset. "Enormous performance and fast charging were permanently available and enabled these records," Schiebe noted, reflecting on the Nardò endurance tests.

The presence of Federal Transport Minister Patrick Schnieder at the opening underscored the importance of the project for Germany’s industrial standing. By anchoring the production of high-performance electric motors within Germany, Mercedes-Benz is securing domestic expertise in the critical components of the energy transition, moving beyond simple battery-electric vehicle assembly to the vertical integration of core propulsion technology.

Implications: A New Standard for Manufacturing

The production of these motors is a masterclass in modern manufacturing complexity. Mercedes-Benz implemented 98 distinct process steps for the assembly of the axial flux motor, 65 of which are new to the company, and 35 of which are global industry firsts. This has resulted in more than 30 patent applications.

The Challenge of "The Marriage"

Perhaps the most impressive aspect of the production line is the final assembly, or "marriage," of the components. The stator is placed between the two rotor disks, which contain powerful magnets. During this step, the assembly must overcome magnetic forces of up to 9 kN—equivalent to 900 kilograms of force—while maintaining a tolerance of less than 0.1 millimeters.

To achieve this, Mercedes-Benz utilizes:

• AI-Driven Quality Control: Real-time optical monitoring documents every connection.
• Intelligent Robotics: A proprietary algorithm adjusts the position of the components in the final 0.5 seconds of the process, using high-frequency control pulses to ensure perfect alignment.
• Laser Welding: Because the copper windings and plastic structures are highly sensitive, the company utilizes precise laser welding to minimize heat impact, ensuring the motors are oil-tight and structurally sound without the risk of thermal damage to neighboring parts.

The Future of Automotive Engineering

The success of the Berlin-Marienfelde project has profound implications for the automotive sector. It proves that the "impossible" can be industrialized if the investment in manufacturing technology matches the innovation in product design.

As the electric vehicle market matures, the focus is shifting from "simply having an electric motor" to "optimizing the propulsion system for specific vehicle dynamics." By mastering the axial flux motor, Mercedes-Benz has not only set a new performance benchmark for the AMG brand but has also created a blueprint for the next decade of electric motor production. This is no longer just a trend; it is the arrival of the "V8 of the electric age," and it is coming from the heart of Berlin.