How Rare Earth Metals are used in Electric Motors and Batteries

Rare earth metals, or lanthanoids, have special properties, such as catalytic, chemical, electrical, metallurgical, nuclear, magnetic or optical, making rare earth metals valuable for application in an ever increasing host of advanced technological functions.

The magnetic lanthanoids are used in everything from mag lev trains to LED displays where light and a coin battery are used. They are in bike dynamos and in the permanent magnet motors of power tools and other small electrically motorized applications.

But, as mentioned earlier, these substances can often be difficult to extract, as they can reside in ores, and require complicated and multi stage processes in order to extract them in usable form. Also, there are now so many uses for rare earths with magnetic and other properties that there are ongoing investor battles, primarily with the Chinese, who cornered the market for a while, to free up some of the available supplies of them.

The primary use of lanthanoids for the hybrid car industry are in creating the permanent magnets fields used in the hybrid car batteries, or in helping to control and maintain the magnetic fields. The Toyota company Prius is the most prevalent consumer of lanthanoids, with a major production goal. The Prius uses up to 2.2 pounds of lanthanoid in its batteries, with more needed to increase the future capacities of the battery.

The four “rare earth metals”, or lanthanoids, used in electromagnets are Lanthanum, neodymium and dysprosium and terbium.

Lanthanum is made from the minerals monazite and bastnasite. It is a soft, malleable, easily oxidizing metal The Toyota Prius uses 22-33 pounds, or 10-25 kg of lanthanum.

Neodymium is the major component of hybrid car batteries. Neodymium has the most powerful magnetic potential of the lanthanoids. 2.2 lb, or 1 kilogram of neodymium is used in the Toyota Prius, with increases on the way. Neodymium is also used in wind turbine generators, all forms of motors, loudspeakers, headphones, guitar pickups and most computer hard drives where magnetic properties are needed.

Dysprosium is a metallic silver lanthanoid that is found in several minerals, including xenotime, monazite and bastinite and several others.  Dysprosium is used along with terbium to stabilize the magnetic properties of the neodymium in hybrid car batteries, nuclear reactors and data storage devices.

Terbium is also used in hybrid car batteries to help the neodymium to maintain its magnetic properties. It is a white-silver metal that is more stable in air than other lanthanides. Terbium is the most reactive of the elements to magnetic fields and helps, along with dysprosium to stabilize the molecular structure of neodymium magnets and to keep the atoms in line. As a result, terbium is used in many actuators and magnet based electronic devices.

Wikipedia Lanthanum
http://en.wikipedia.org/wiki/Lanthanum

Wikipedia neodymium
http://en.wikipedia.org/wiki/Neodymium

Wikipedia Dysprosium
http://en.wikipedia.org/wiki/Dysprosium

Wikipedia Terbium
http://en.wikipedia.org/wiki/Terbium

Wikipedia Rare Earth Magnet

http://en.wikipedia.org/wiki/Rare-earth_magnet

Reuters