Rare earth free motor designs with MnBi

Currently, electric motors used in electric vehicles currently rely on critical materials like neodymium and dysprosium. These materials are subject to wide price swings, and as demand increases for electric vehicles, availability and price may become prohibitive. Additionally, no domestic suppliers or manufacturers of these materials currently exist in north America, and 90% of supply is from China. Executive Order 13817, directs agencies, including DOE, to developing domestic alternative technologies and supply chains that do not rely on foreign sources or reduce demand of these critical materials. This Project seeks to transition DOE-developed MnBi permanent magnets to industry, and to develop permanent motor alternating current (PMAC) motor designs meeting 2025 EETT roadmap goals for electric traction motors. Using non-rare-earth magnets can dramatically reduce the cost of traction motors, while incorporation of advanced materials, including low loss stator laminates and covetic rotors to enhance heat removal will be evaluated in motor design trade studies to meet 2025 motor goals. In this STTR, Powdermet will replicate AMES lab powder production and MnBi bulk magnet production, and scale magnet production to larger sizes suitable for building prototype motors. Rapid consolidation of the MnBi with engineered interfaces using SPS and traditional hot pressing will be used to produce bulk magnets. Finite element analysis of PMAC motor designs incorporating advanced materials will be carried out, comparing traditional NdFeB magnets and MnBi, as well as advanced nanocrystalline stator materials. Motor cost and performance will be mapped as a function of motor design, magnetic (soft and hard) materials, and thermal performance/heat generation, efficiency, and power will be evaluated as a function of speed for a 100KW PMAC motor. Electric Vehicles are expected to reach 35% market share in the 2030’s, and will require lower cost and more efficient traction motors. MnBi can eliminate rare earth dependance, while reducing cost of magnets by 50% over ferrite and NdFeB materials. Greater use of electric vehicles reduces greenhouse gas, NOx, and particulate emissions, and reliance on fossil fuels.