Copper has ruled electric motor windings for decades. That ironclad grip is slipping.
BorgWarner has secured its first commercial supply contract for aluminium-wire electric motor (eMotor) technology from a major Chinese automaker. The systems will drive hybrid passenger cars across multiple architectures, pulling duty as generator units and traction motors for auxiliary drive setups. Assembly lines kick off in the fourth quarter of 2026.
For car buyers, heavy electric hardware inflates sticker prices and curbs fuel economy. Swapping copper for aluminium addresses both friction points directly at the supplier level.
Automotive engineers traditionally avoid aluminium conductors because the metal carries higher electrical resistance than copper. BorgWarner bypassed the hurdle by refining its hairpin winding profiles and connection joints specifically for hybrid duty cycles.
The engineering payoff is substantial. According to technical data released by BorgWarner, the aluminium-wire eMotor matches the peak torque and peak horsepower delivered by a conventional copper-wound unit. Yet the conductor wire inside weighs over 60% less and cuts wire material costs by more than 80% compared to identical copper specifications.
| Performance Metric | Aluminium-Wire eMotor | Conventional Copper Baseline |
|---|---|---|
| Conductor Wire Weight | Over 60% Reduction | Baseline (100%) |
| Conductor Wire Cost | Over 80% Reduction | Baseline (100%) |
| Peak Torque Output | Parity with Copper | Baseline Target |
| Peak Power Output | Parity with Copper | Baseline Target |
| Target Powertrain Duty | Generator & Auxiliary Traction | Standard Primary / Secondary |
| Production Start Window | Q4 2026 | Active Production |
Lighter generator motors trim front-axle mass in complex parallel-hybrid setups. And lower component manufacturing expenses give carmakers elbow room to price hybrid trims aggressively without gutting their margins.
Market Context: The transition highlights how tier-one component suppliers are restructuring raw material supply chains. By replacing volatile, expensive copper wiring with aluminium hairpin architecture in secondary motors, automakers can insulate hybrid assembly costs from global commodities swings while meeting rigid fleet efficiency targets.
The deal expands a long-running partnership between BorgWarner and the unnamed Chinese vehicle manufacturer, who have collaborated across multiple vehicle product lines for more than 15 years. Instead of importing finished motor modules, BorgWarner will anchor development and assembly within its local Chinese engineering and manufacturing facilities.
Engineers tuned the proprietary hairpin winding, connection geometries, and automated assembly workflows specifically to survive the thermal cycles of hybrid generator systems.
The programme combines aluminium conductors with the company's hairpin winding expertise to deliver weight and cost reductions while meeting the requirements of hybrid generator and auxiliary drive applications." >
Isabelle McKenzie, Vice President, BorgWarner and President and General Manager of PowerDrive Systems
Series integration begins late in 2026. The initial production batch will feed hybrid powertrains across China, testing whether aluminium hairpin stators can reliably displace copper across mainstream assembly lines worldwide.