I believe Tesla's motor does not use rare earth magnets, this is another reason Toyota wants to partner with Tesla.
I dont get it... Rare Earth materials are pretty dang common. Rare Earth materials make superior magnets. So why are we applauding a step backwards?
This explains the rotors that I thought I saw on a special report about the Tesla factory. The rotors appeared to be a copper billet with slots cut parallel to the axis of rotation fed by common bus rings. If so, there would be no need for a permanent magnet rotor. From the Tesla we site: Motor | Roadster Innovations | Tesla Motors Bob Wilson
I work near the soon-to-be Tesla/Toyota factory so sometime on my lunch break I will take a peak and see what materials they are using.
More info Japan develops hybrid car motor free of rare earths - Â Latest news around the world and developments close to home - MSN Philippines News
The advantage of using rare earth magnet is to allow lighter weight and smaller in size for a given power output electrical motor and better regen capability comparing to an common AC synchronous motor.
i'm pretty sure the move is not environmentally motivated. all the rear earth minerals toyota uses comes from china. the move is most like a supply issue. recently, china blocked all mineral exports to japan: China Blocks Rare Earth Shipments Needed by Toyota's Hybrid Cars | LiveScience Etc. actions like these are not uncommon. so the change to non-rare earth magnets is most likely to make sure that they are able to maintain production of their cars and not get held up by magnet supply issues.
Maybe it's just a ploy to make the Chinese think that they don't need their rare earth metal so they've got a better bargaining position?
Just some technical information about the original story. The two “rare earths” mentioned are neodymium and dysprosium. Of those two Neodymium is not actually scarce at all, and could easily be sourced from other places if necessary. Plain Neodymium magnets (Nd Boron Iron) are still extremely powerful, but to get the highest possible magnetic strength (and resistance high temperatures and resistance to demagnetization) about 5% of the Nd is replaced with dysprosium. It’s the dysprosium that is genuinely in short supply with regard to current demand versus known reserves.
The word "Rare" in Rare Earth Elements never implied that they are scarce. Rare Earth Elements are in fact fairly common. The name comes from the fact that they are chemically very, very similar. It was extremely difficult to separate one from another. For years they were assumed to be all one in the same. Because of this difficulty with separation, it was "rare" to have one isolated from the others. Now the term serves nothing but to confuse people into thinking that they are scarce. Tom
Yep I know that qbee. But in this case the dysprosium really is scarce. The point I was making is that PM motors could still be made without the dysprosium, but the magnets wouldn't be quite as robust.
I get your point. I didn't mean to sound as if I were arguing with you. I was only using this thread as a soapbox to address a common misconception about Rare Earth Elements. Tom
well how "rare" is rare earth anyway? as i understand it, there is a demand for the stuff that might be better served elsewhere besides personal transportation so hard to categorize this as a step backwards. maybe we need to look at it as a step in a different direction. we can create a piece of the puzzle that fits our current situation. might be easier than a whole new puzzle.
Well like qbee already said there's not just one "rare earth", it's just the name for a family of similar metals, and some of them aren't scarce at all. Enough Nd is mined each year to make about 8 million Priuses and there's enough known reserves of Nd to keep mining it at that rate for over 1000 years and if necessary the Nd in a Prius could fully recycled anyway. So I don't see why not use it if it makes for an efficient electric motor.
i see your point; but if the same element could be used in mag-lev or another more efficient form of transportation and its costs were greatly reduced because the need or demand for its use in other applications were no longer critical...
