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Trick engineering from the General here. Much of the polution caused by EV's is actually baked into the mining of rare earth minerals for use in the batteries and motors.

First off, Motor Trend reports that the smaller motor in the General Motors Voltec 2.0 powertrain eliminates rare earth materials altogether by using simple ferrite magnets. These magnets are optimized by their arrangement into a dozen regularly-spaced clusters encircling the central rotor, with each cluster containing four concentric elements. This allows for a maximization of both magnetic, and reluctance (or “magnetic resistance”) torque.
The larger motor, meanwhile, does contain a rare earth metal in the form of the element Dysprosium, but its presence is reduced thanks to some clever engineering. Says Motor Trend, a trick of metallurgy concentrates the Dysprosium into the corners of the larger motor’s magnetic elements, where it’s most effective. Together, not only do the complimentary motors of the new Voltec powertrain manage to use 80 percent less rare earth metals, but they also prove to be ideal counterparts in the revised system. The small motor hits peak efficiency at 5-9k RPM, at relatively lower torque, while the larger motor peaks in efficiency at higher torque, at around 2-4k RPM.
http://gmauthority.com/blog/2015/05/motor-trend-dissects-the-2016-volt-powertrain/
Original source http://blogs.motortrend.com/1504_dissecting_chevys_2nd_gen_moonshot_technologue.html
 

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Less rare earth metals sounds like a good thing. I think that just means they will use the same amount to make more cars because I doubt the mines are decreasing their production because of this. Good from a PR standpoint though.
 

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Less rare earth metals sounds like a good thing. I think that just means they will use the same amount to make more cars because I doubt the mines are decreasing their production because of this. Good from a PR standpoint though.
Well they technically are depending on your frame.

If GM is using less metals per unit but still buying the same gross quantity they are keeping the mine from increasing their production. Its cost efficiency from the general, they can make each bulk buy go further thus generating more profit right.

If there wasn't an engineering breakthrough either GM hits the mine up for more quantity or GM simply makes less electric vehicles...

PR spin or practical solution? There's no reason GM shouldn't celebrate...
 

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GM has advanced the design and producton of electric motors since Cadillac installed the first electric engine cranking system (we now call a "starter"), which was designed by Charles Kettering at GM (who also designed the advanced spark ignition system). GM developed and designed the Magnequench electric motor, which was first used in the Sunraycer (the father of the GM EV1 and grandfather of the Volt), and now uses more advanced materials and manufacturing methods for the Chevy Spark EV motor, which will be improved for the Chevy Bolt EV.

All of these advancement will give the BEV owner the benefits of a simpler, powerful, and reliable electric traction motor, which will be enclosed in transmission fluid as a lubricant, coolant, and preservative (no oxygen), so it can supply excellent service and long vehicle life. Electric motors have very few moving parts, little friction, low heat loss, and no preventive maintenance*. So if a BEV such as the Bolt EV may cost more than an equivalent ICEV, the little maintenance and very long life compensates and saves the expenses in fuel and maintenance that the ICEV needs.

*The Spark EV recommends a transmission fluid change every 97,500 miles or ten years!
 

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I always felt a bit uneasy about those really long service intervals which as a hands-on owner will make me want to check things out for myself from time to time... checking the state of the fluid on some regular basis of my own that I setup.
 
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