We're not sure what "grain boundary diffusion" means, but it has something to do with the Nissan Leaf all-electric vehicle substantially cutting its use of rare-earth minerals in its electric motor, so we're all for it. The Japanese automaker says that, starting in November, it began building electric motors for the Leaf that use 40 percent less of the rare-earth mineral dysprosium than before. Dysprosium was used to make the fast-spinning magnets inside the electric motor more heat resistant, but Nissan found a way around much of that use, hence the super esoteric terminology "grain boundary diffusion."

The development marks good press for Nissan because it lessens the need for rare earth metals to be extracted from places such as China. Smaller amounts of rare earth metals also means lower cost, which can be a big help. In November, Nissan chief Carlos Ghosn said the automaker would miss its goal to sell 20,000 Leafs in the US this year. Nissan has, however, somewhat closed the gap between this year's sales and last year's during recent months. US Leaf sales in November more than doubled from a year earlier, and are down just 4.5 percent year-to-date.

Read Nissan's press release below, and check out its two-minute video here.



Show full PR text
Building a Greener LEAF

The Japan-market Nissan LEAF
Dec. 11 – Yokohama - Nissan's zero-emission LEAF electric vehicle just became even greener.

The latest version of the industry leader, introduced in Japan in November, has a new electric motor using 40% less of the rare-earth mineral dysprosium – without affecting performance.

"The driver will not notice any differences. Vehicle performance will remain unchanged," said Kiyoshi Takagi, deputy general manager in Nissan's Materials Technology Planning Group.

"In fact, the overall performance increased, so drivers don't need to worry."

The rare-earth element dysprosium
Dysprosium is added to the LEAF's electric-motor magnets to make them more resistant to heat as they spin at speeds of up to 10,000 rpm.

A new process called "grain boundary diffusion" allows Nissan to drastically cut rare-earth content in use a way that may extend beyond EVs and hybrids to use in other automotive applications.

"Dysprosium is used not only in the motor to power EVs, but also in components of existing internal combustion engines," said Ryou Murakami, manager of Nissan's Advanced Materials Laboratory.

Using less rare earth content is a goal of the Nissan Green Program 2016, part of a commitment to minimize use of scarce natural resources.

Cutting dysprosium in the LEAF also helps Nissan avoid supply constraints, with the large majority of the element mined in China, and lower costs as demand grows.

"Rare-earth metals, dysprosium in this case, are a scarce resource, which also impacts the environment during the mining process," said Takagi. "Reducing the usage of such resources will reduce this impact."

For a new generation of Nissan LEAF owners, greener production is already complementing zero-emission motoring.


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    • 1 Second Ago
  • 21 Comments
      Val
      • 2 Years Ago
      Such a revolutionary change, and to think that an electric motor that uses NO rare earth metals was invented barely 100 years ago.
        2 wheeled menace
        • 2 Years Ago
        @Val
        lne; Tesla produces lower amounts of motors ultimately, but they have gone with an AC Induction motor. I think Nissan can do it too. And with the stuff that's going on with the Diaoyu islands in Japan, i'd think they would want to get around to doing what Tesla's doing preeeeetty soon :)
          Marcopolo
          • 2 Years Ago
          @2 wheeled menace
          @ Val, Some Australian's, are fearful of foreign investment and xenophobic. Australia has a population of only 23 million, and surrounded by major manufacturing nations, with much cheaper labour and volume production savings, doesn't offer much scope for manufacturing of traditional products. It's extremely difficult to persuade GM, Ford and Toyota to continue manufacture in Australia. Australia is not a good environment for old fashioned heavy industry. The idea of the PRC 'building plants' in Australia is unrealistic. PRC investment is still relatively small and not the bogyman that people think. Australian miners are the highest paid, and enjoy the best conditions in the world. While it's true that an influx of Asian money has caused high end real estate prices to increase in the major cities, the the idea that Chinese investment in agricultural properties is somehow immune to the vagaries of the weather, and more economic than any other capital investment, is absurd. Nor does PRC investment contain any real political influence. Just owning an asset, makes the investor a hostage of the local government. Building a plant and controlling large scale local employment, provides far greater scope for political influence. Just owning an asset, means the investor is constantly at the whim of local tax regimes and local economic policies. The concept of 'blackmailing' PRC ore importers by withholding raw material exports, is naive. The result would be catastrophic for the Australian economy, a boon for competitors, and the flight of Australian mining companies and capital to other more reliable nations.
          Spec
          • 2 Years Ago
          @2 wheeled menace
          The USA has plenty of rare Earth metals as well. However, we have a regard for worker safety, worker health, and environmental damage such that they are more expensive than from China. I suspect the same is true in Oz.
          Marcopolo
          • 2 Years Ago
          @2 wheeled menace
          @ 2 wheeled menace Easy there 2SM ! Australian rare earth mining is just becoming viable. Yen is just as acceptable as Yuan Renminbi !
          Val
          • 2 Years Ago
          @2 wheeled menace
          Since the chinese are buying up australia (land, mines, rights to mineral deposits) it is very likely that nissan will have to buy it from he chinese, even if mined in australia.
          Marcopolo
          • 2 Years Ago
          @2 wheeled menace
          @ 2 wheeled menace Yep, also huge deposits of lithium and...well just about everything ! It only limited by the costs of extraction.
          Marcopolo
          • 2 Years Ago
          @2 wheeled menace
          @ Spec and Val , Well, Australia's a big place and very accustomed to dealing with foreign investment. However, in the case of rare earth mining, the newest technology is very highly mechanized and not labour intensive nor particularly pollutant. PRC companies have been deterred from direct rare earth mining investments in Australia since 2005. Australia has a very experienced, well capitalized and aggressively competitive mining industry.
          2 wheeled menace
          • 2 Years Ago
          @2 wheeled menace
          I didn't know that Australia had some of that stuff lying around; interesting to know!
          Val
          • 2 Years Ago
          @2 wheeled menace
          Be that as it may, the growth of chinese investment in mining is staggering, and is causing concern for australian citizens and some politicians. Australia would be much better off using these resources in products, for domestic and export markets, instead of shipping ores or refined minerals abroad.
          Val
          • 2 Years Ago
          @2 wheeled menace
          and they could do that in the same way the chinese did it, if you want our minerals, build a plant that uses them here, coz we ain't exporting those babies.
        lne937s
        • 2 Years Ago
        @Val
        It is about balance of size, weight, efficiency, cost, production complexity, product consistency, durability and material availability. You could pick other motor designs (switched reluctance, etc.), but Nissan picked this combination for the LEAF.
          Val
          • 2 Years Ago
          @lne937s
          This video shows that even if this process is the only significant thing done for the motors, it is already vastly more complex than just winding copper. There is no possible way that the cots of manufacturing a motor using permanent magnets will be lower than one using none. Material availability is exactly the thing that is making nissan try to reduce the amount needed. AC induction has no scarce materials used. Durability is obviously inherently worse on a PM motor, since the magnetic field collapses at high temperature, that is why they dope the magnets, to withstand higher temperatures. For the 1-2% gain in efficiency and the 5-10 kg difference, nissan did pick the worse option.
      fairfireman21
      • 2 Years Ago
      Who realy cares I still will never buy one!
        Marcopolo
        • 2 Years Ago
        @fairfireman21
        @ fairfireman21 No charging facilities under your bridge ?
        Spec
        • 2 Years Ago
        @fairfireman21
        So if you don't care then obviously no one else could possibly care. That explains a lot about you.
      cointel
      • 2 Years Ago
      A123 would still be in business if 200-300 mile ranges were achieved increasing range and boosting sales.
      cointel
      • 2 Years Ago
      How's come the EV1 made by GM went 100-140 miles in 90's with NiMH and lead acid batteries!, yet the nissan leaf, gm spark, and ford car barely get 70-80 miles of range. No wonder their sales are abysmal. Is somebody trying to undermine the sales while looking like an effort is being made to produce electrics? I know Tesla, took away the argument that electric cars could not be made.
        Nick Kordich
        • 2 Years Ago
        @cointel
        @cointel - There are three main reasons you haven't seen a significant improvement in range: 1. You are comparing range estimates from different tests. The EV1's 140 mile range was achieved on the SAE J1634 test. New EVs have to give their range according to the more demanding EPA five cycle test. The Coda sedan's J1634 range was 133.6 miles, according to their brochure - almost identical to the EV1 with NiMH batteries - but only rated 88 miles on the EPA's current tests. At 20mph (the average speed on the J1634), you can drive a Tesla Model S over 400 miles, as has been demonstrated recently in another article. 2. The EV1 was a much smaller car. The EV1 was a two-seat subcompact with limited cargo capacity. The Leaf is a five seat, four door compact with two and a half times as much cargo space. The Leaf is a full 10" taller than the EV1 and less aerodynamic, primarily to accomodate passengers. According to Wikipedia: "GM investigated the possibility of making the EV1 a four seater, but ultimately determined that the increased length and weight of the four seater would reduce vehicle's already limited range to 40–50 miles." 3. The emphasis has been on driving down cost, not increasing range. The EV1 was given an unrealistic price tag of $34,000, but as Ziv mentions it cost some multiple of that to actually build it. The Nissan Leaf has a very similar base price, but Nissan must actually make money on it. Also, adjusted for inflation, the EV1's official price (less than a third of what it cost to make, going by Ziv's comment) would be $50,000 in 2012 dollars. To keep costs down, the easiest thing to sacrifice is the capacity of the battery pack. Doing so reduces range, but increases interior volume and improves the car's handling, acceleration, braking and efficiency. The Leaf and other EVs qualify for CARB credits for the manufacturer and HOV lane access and a tax credit for buyers, while having range of twice the average daily commute - in other words, range hasn't increased beyond 75-100 miles or so because that's good enough between the current buyers and the manufacturers, and that's satisfying their CARB commitment. That may change in the next 10-20 years, as energy density tends to increase as fast as or faster than price/kilowatt hour decreases, but for now, manufacturers seem to think they've found the sweet spot in terms of range.
        Ziv
        • 2 Years Ago
        @cointel
        cointel, because it cost around $120,000 to build each EV1 and it was nearly hand crafted. And that doesn't count the Billion dollars that GM sunk into its development. Tesla is currently proving just how hard it is to build a full utility BEV (more than 200 mile AER) for less than $100,000, and Tesla has the advantage of LiIon batteries costing much less now than NiMH batteries cost when the EV1 was being built. The Volt battery probably costs around $8-$10k to produce now, though it cost more 2 years ago. The EV1 battery was similar in size (kWh) but the most positive account of how much it cost I can find is $20-$30k. http://www.greencar.com/articles/20-truths-gm-ev1-electric-car.php
      Mami
      • 2 Years Ago
      What gives?
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