Mercedes-AMG GT XX: Three Axial Flux Motors & 850 kW Charging
At the 2025 Frankfurt Motor Show, Mercedes-AMG lifted the veil on its GT XX concept—a cutting-edge electric supercar built on the brand’s new AMG.EA architecture. Boasting three in-house axial flux motors, an 800 V battery pack with NCMA chemistry, and over 850 kW peak charging capability, the GT XX sets a new benchmark for continuous track performance and rapid turnaround.
Key Technical Specifications
- Drive Units: Three axial flux motors (1× front, 2× rear) delivering combined peak power >1,000 kW and torque exceeding 1,500 Nm.
- Battery: 800 V NCMA cylindrical cells (nickel/cobalt/manganese/aluminum cathode; silicon-doped graphite anode), 300 Wh/kg energy density, 3,000 cells, structural skateboard design.
- Charging: Prototype CCS station outputting 1,000 A for >850 kW charge; 400 km (WLTP) in 5 minutes.
- Cooling: Direct liquid-immersion cell cooling with non-conductive oil pumped through micro-channels.
- Weight Savings: Axial flux motors are 67% lighter than comparable radial flux units.
1. Advanced Battery Chemistry and Pack Design
The GT XX’s battery pack employs nickel/cobalt/manganese/aluminum (NCMA) cathodes with silicon-enhanced graphite anodes to achieve 300 Wh/kg. Mercedes engineers opted for 46 mm × 200 mm cylindrical cells—narrower for faster thermal diffusion. Direct-cell cooling channels circulate a non-conductive oil, extracting up to 50 kW of heat under peak loads. By integrating the pack as a structural chassis member, the concept ensures rigidity, crash resilience, and optimized weight distribution.
2. Axial Flux Motor Innovation
“Axial flux motors offer a power density advantage of up to 20% over radial flux designs,” explains Dr. Jane Smith, EV drivetrain specialist at Stuttgart Institute for Automotive Research. “Their pancake geometry facilitates efficient cooling and shorter magnetic flux paths.”
Mercedes-AMG’s in-house Berlin facility developed 35 world-first manufacturing methods to stamp ultra-thin stator laminations and bond high-strength rotor magnets in a torque-dense assembly. Each motor spins up to 16,000 rpm, delivering 500 Nm per unit, and pairs with a compact single-stage gearbox. The front unit handles regenerative braking at up to 300 kW, while the twin rear units manage full traction torque.
3. Ultra-Fast Charging Ecosystem
To harness over 850 kW input, Mercedes collaborated with European HPC specialist Alpitronic. The custom CCS charger operates at 800 V/1,000 A, featuring liquid-cooled cables and dynamic power-management algorithms to maintain peak rates across 10–80% SOC. Industry observers note Tesla’s recent unveiling of 1.2 MW Superchargers and Ionity’s plan to upgrade to 900 V/600 kW, highlighting a rapid infrastructure arms race.
4. Manufacturing & Scalability
While the GT XX is a concept, AMG.EA’s modular design is slated for two production models in 2026, including an AMG SUV. Components leverage existing Mercedes-Benz EV plants in Tuscaloosa (battery modules) and Berlin (motors), ensuring volume scalability. Industry analysts predict annual output of 50,000 units once the supply chain ramps up.
5. Thermal Management Strategies
Continuous track performance demands relentless cooling. The GT XX employs a dual-loop system: high-flow oil channels inside the pack and dedicated coolant circuits for inverter, motors, and power electronics. Active grille shutters and wheel-arch air curtains optimize airflow, drawing lessons from endurance racing prototypes like Porsche’s 963 LMDh.
6. Charging Infrastructure & Partnerships
Mercedes-AMG is expanding partnerships with major European charging networks—Ionity, Fastned, and upcoming Ultra-Charge alliances—to deploy 800 V/500+ kW stations at key motorsport venues and highway hubs. A planned smartphone integration will reserve stalls, monitor station health, and dynamically balance grid load via vehicle-to-grid (V2G) capabilities.
Expert Perspectives
“Delivering continuous lap-after-lap EV performance is the holy grail for performance brands,” notes Michael Schiebe, CEO of Mercedes-AMG. “With AMG.EA, our goal is zero thermal fade and seamless power delivery, reminiscent of our V8 heritage.”
Conclusion
The Mercedes-AMG GT XX concept crystallizes the marriage of cutting-edge battery chemistry, high-density axial flux motors, and next-gen charging infrastructure. As AMG accelerates its transition to fully electric powertrains, the GT XX offers a tangible preview of production models that promise to redefine supercar performance in the EV era.