“Rare earth elements” are a set of 17 chemical elements in the periodic table. Though many of these elements are not actually rare, their geochemical properties make it difficult to find them in concentrated forms that can be extracted for use easily or economically. Rare earth elements have been used in conventional internal combustion vehicles for many years in small quantities. However, electrified vehicles – including hybrids, plug-in hybrids and full electric vehicles – use larger quantities of rare earth elements in magnets in their electric motors and in their more complicated battery systems. As electrified vehicle production increases, the importance of the supply and production of certain rare earth metals is growing in importance to automotive companies. These elements are also used extensively in nonautomotive applications, such as electronic touch screens and mobile phones.
Rare earth elements pose both economic and sustainability challenges. The growing demand for rare earths has called into question future supply and material costs. They are also a concern due to the geographic concentration of supply and environmentally unsustainable mining practices.
Ford has taken a proactive approach to understanding and minimizing the issues associated with rare earth elements in our vehicles. We began by assessing the amount of rare earth elements in our vehicles and where they occur. This is, in fact, a very challenging task because rare earths are used in small quantities, in a large number of components, and by suppliers far upstream in the supply chain. We estimate that approximately 0.44 kg of rare earths are used in a typical conventional sedan, with approximately 80 percent of the rare earth content in magnets. Conventional vehicles primarily use neodymium, which is used in batteries and magnets, and cerium, which is used mainly in catalytic converters. Relatively larger amounts of rare earths – primarily neodymium and dysprosium – are used in full hybrid electric vehicles (HEVs). A typical HEV sedan with a nickel-metal-hydride battery uses approximately 4.5 kg of rare earth metals. HEVs with lithium-ion batteries contain approximately 1 kg of rare earths. We are still evaluating the rare earth content in plug-in hybrid electric and full battery electric vehicles.
Our primary focus in addressing rare earth elements thus far has been to reduce the need for them in our electrified vehicle battery systems. Our third-generation hybrid system significantly reduces the use of rare earths compared to nickel-metal-hydride batteries and other lithium-ion battery systems. We have reduced the use of dysprosium by approximately 50 percent in the electric machine permanent motor magnets used in our hybrid system. This new technology reduces the cost of our hybrid systems by 30 percent, largely by reducing the use of dysprosium, which is the most expensive rare earth element used in electric motor magnets. The new system is also 50 percent lighter and 25 to 30 percent smaller than previous-generation hybrid batteries, contributing to better fuel efficiency. We expect this new hybrid battery technology will save up to 500,000 pounds of rare earth metals annually.