Rare earth elements, or rare earth metals, are a collection of several chemical elements in the periodic table: the ones that most of us struggled to remember in our chemistry classes. Most of these “rare earths” are actually plentiful in the earth’s crust, but they are so dispersed that it is difficult to mine them. When rare earths are concentrated enough to make mining possible, their extraction requires high amounts of energy and water.
So while it is easy to get excited over the advances in battery technology and “hybrid” or electric cars, the growing global demand for rare earths is problematic. Most rare earths are currently mined in China, and other regions, like South America, have concentrations of these elements in areas that are both remote and in extremely dry climates. That new car or electronic gadget of yours may be super sleek or help you save on your gasoline bills, but the elements needed to keep those batteries humming consume their own significant carbon footprint. Then you have the prospect of China restricting the these rare earths’ trade, and other countries that have such reserves cannot move fast enough to provide the world a reliable supply. General Electric, however, is one company that may have a solution.
GE Global Research, with a Department of Energy grant, is working on technology that could mitigate demand for rare earths like neodymium, dysprosium, and terbium. The project on which this GE division is working involves the development of nanocomposite magnet materials. These nanocomposite materials include nanoparticles that include traces of such valuable rare earths like neodymium, as well with more commonly found elements like iron or boron. If “nano-structured” correctly, these magnets could interact in a way that could create increased magnetic properties than what is found in today’s magnetic alloys found in batteries currently on the market.
Two advantages of these new nanocomposites come to mind: these new alloys could be even lighter than batteries currently in our favorite vehicles or devices. They would also use less rare earth metals, the price of which has spiked in recent years. For those of use who remember our high school physics class, these new alloys would benefit from “exchange coupling,” a process by which the overall magnetic properties would be even more intense than the sum of their parts. Exchange coupling is not possible in pure magnetic materials, but is evident in composites made from mixtures of nanoparticles.
GE is mum on the materials it is currently researching. The company believes these new materials could be available in a few years, but its researchers are facing hurdles, including the inability to scale; and so far, only thin films of these nanocomposites can be manufactured.
So the technology is young, but GE’s work is a promising step. Between diminished resources, increasing energy prices, peak oil, and a growing middle class around the world, research like that of GE’s is critical in weaning countries like the US off of fossil fuel imports. Better magnets can also dispel any talk that China could end up starting a trade war over these rare earths that are critical for everything from wind turbines to smartphones.