Toyota says it has invented a new magnet for high-energy applications such as electric motors that uses a fraction of the amount of neodymium of a standard iron, boron, neodymium (NdFeB) magnet.
Rare-earth magnets are used in many hybrid vehicles, some all-electric vehicles, and in other applications like wind turbines and robotics.
Although “rare” is a bit of a misnomer for a material like neodymium (high demand has led to relatively high production volumes), Toyota notes that “there are concerns that shortages will develop as electrified vehicles, including hybrid and battery electric vehicles, become increasingly popular in the future.” That concern is compounded by the concentration of rare-earth mining; although attempts have been made to mine rare-earth metals in the US and other parts of the world, a preponderance of rare-earth mining occurs in China.
The new magnet Toyota developed also uses no terbium or dysprosium, which can be added to neodymium to improve its operability at high heat, above 100 degrees Celsius (212 degrees Fahrenheit). In fact, mining consultancy Roskill notes that few automakers use terbium in magnets anymore, though dysprosium is still commonly added to magnets with neodymium.
The magnet uses less-expensive rare-earth metals lanthanum and cerium. Certainly, this doesn’t get rid of many of the issues with neodymium: lanthanum and cerium are still predominantly mined in China and, as with most rare earths, they can be environmentally destructive to produce. But Reuters notes that while neodymium costs about $100 per kg and dysprosium costs about $400 per kg, lanthanum and cerium cost about $5 to $7 per kg. Ideally, a cheaper magnet could result in cheaper hybrid and all-electric vehicles.