Honda to Launch Electric Motor That Contains No Heavy Rare-Earth Metals

Honda Motor Co. and Japan’s Daido Steel Co. have developed an electric motor that doesn’t use heavy rare-earth metals.

The motor, which Honda describes as an industry first, will be introduced later this year in Japan in the hybrid variant of Honda’s Freed minivan. Other Honda hybrid models are expected to switch to the new motor in coming years.

Heavy rare-earth metals such as dysprosium and terbium provide the high heat resistance properties required for an electric motor’s neodymium magnets. But prices have soared in recent years as demand increases and China, which accounts for more than 80% of the global production, has limited exports of the minerals.

Daido uses a hot deformation process to make the neodymium magnets instead of the typical sintering method. This enables the magnet’s crystals to be precisely aligned in smaller structures and provide greater heat resistance without the need for heavy metals, according to the partners. Neodymium is a light rare earth metal that is abundantly found in many regions.

Honda redesigned the motor design to accommodate Daido’s new magnet. It also revised the shape of the rotor to optimize the flow of the material's magnetic flux.

Daido will begin making the new magnet next month. The company also is working with Toronto-based Magnequench International Inc.to develop new types of powders to enhance magnetic properties.

Several other carmakers and suppliers, including Mitsubishi Electric, Nidec and Yasukawa Electric, also are developing non-rare earth magnets for electric motors.