You may have seen some recent press regarding reports that a Toyota supplier is developing an electric motor for use in the Prius and similar hybrids that does not need Rare Earth Elements (REE) in the magnets. A Toyota Prius electric motor currently uses 1 kg (2.2 lb) of neodymium plus dysporium, and yet supplies are increasing in price and decreasing in availability after China (the source of 95 percent of the world’s REE according to an autoevolution blog) capped supplies this year to 4,500 tons. A Bloomberg article adds further detail: “China’s government cut export quotas for the first half of 2011 by 35 percent last month which in turn followed a 72% reduction in the second half of 2010, the paper said.
The Toyota supplier, Aisen Seiko Co., is Japan’s biggest manufacturer of transmissions, with 65 percent of their output going to Toyota or their subsidiaries, and so understands the demands of the automotive industry intimately. The firm is apparently drawing on research done by New Energy and Industrial Technology Development Organization (NEDO), which, jointly with Hokkaido University, is reported to have developed a ferrite iron-based motor that by careful positioning of the magnets avoids the performance-enhancing rare earth elements in the alloy. However, no comparable performance figures are quoted in the reports and it seems doubtful from the previous work if a ferrite motor is going to be pound-for-pound as effective or efficient as a rare earth-enhanced motor.
If successful, the project holds out the enthralling promise of electric motors in a host of applications that do not need REE. After all the fuss over scarcity and the need for funding of supply options outside of China, wouldn’t that be a turn up for the books. Unfortunately, we are still some way from weaning ourselves off REE, even if this particular project achieves some success. Automotive electric motors, just like about every other electronic component in our everyday lives, are getting smaller and smaller at the same time as increasing in power. Conventional theory has said the ferrite motor may achieve a similar result but is likely to be larger and heavier than its REE equivalent. However, a report last year on research done by Hitachi suggests the progress they and others like Daikin Industries and Osaka Prefecture are already experiencing is bearing fruit. In an article in Techeye.net, both organizations are reported to have made progress with motors of up to 5 kw performing with very similar results to REE motors, but using ferric oxide. Hitachi is starting to use these in place of REE motors in air conditioners and is working on developing larger 20 kw versions. According to the article, hybrid car motors are required to produce some 50 kw of power so Hitachi’s development has some way to go, but suggests that there may be promise in the approach.
If electric motors can be made without REE, what about other applications? For some there may really be no alternative to REE, but this research suggests that we may not be as totally reliant on REE as we thought and good old R&D may yet reduce our dependence on China’s dwindling rare earth supply.
MetalMiner and its sister site, Spend Matters, along with Nucor, will host a live simulcast, International Trade Breaking Point on March 1, 2011. If your company sources products from overseas, you will not want to miss this half-day event: