China sent shockwaves through the high technology world last year when it blocked exports of rare earth metals for two months. The resulting shortage has seen prices soar and made major companies nervous.
Rare earth metals are an essential part of many high-tech products including phones, missiles and batteries. China produces 30% of the world’s supply yet fulfils 97% of the world’s demand for them and last year’s action has demonstrated how vulnerable such a monopoly leaves many manufacturers and governments.
The ban on exporting rare earth metals to Japan followed a diplomatic row over disputed islands and lasted for two months, only being lifted in November 2010. The impact was relatively small but did illustrate how precarious the supply was and prompted manufacturers to seek alternatives. China has also reduced the amount of rare earth metals being exported in recent years with the 2010 export quota of 24,280 tons being reduced by 30% from 2009 levels.
Despite their name, rare earth metals are fairly plentiful in the earth’s crust; it’s just that China is one of the few countries that has invested in the infrastructure necessary to extract them. The United States, Canada and Australia stopped large-scale extraction in the 1990’s as supplies from China were so plentiful – and cheap.
The mining and use of rare earth metals is controversial, with environmentalists pointing out that their extraction causes huge environmental harm. Mildly radioactive slurry and acid run-off are the two most damaging side effects.
Others point out that the increasing production and sale of electrically-powered cars – all of which rely on batteries containing rare earth metals to a greater or lesser extent – means that demand is expected to exceed supply in just a few years, further stimulating research into alternatives.
In 2000, 40,000 tons of rare earth metals were sold; in 2010 sales of rare earth metals reached 120,000. By 2014 it has been predicted that 200,000 tons will be needed to meet worldwide demand from the high-tech industry.
However, two major forces in electric car development are working independently to reduce their reliance on rare earth metals. If successful, the innovations promise to significantly reduce the price of all-electric vehicles.
Toyota Motor Corp., manufacturers of the popular Prius hybrid car, is developing a new type of electric motor, which will reduce their dependence on rare earth metals. Whilst Toyota have previously staked a claim to petrol-electric hybrid cars they aim to have an all-electric car on sale in 2012 in the United States, Europe and Japan. They are also working with Tesla to make an electric Sport Utility Vehicle (SUV).
Also working to solve the problem is Professor Nobukazu Hoshi of the Tokyo University of Science, who has developed an electric car that doesn’t require any kind of rare earth metals.
The Professor said of his work:
“In recent years the price of rare earth metals has risen, so we have worked on development of a car motor with the same functionality of a hybrid car motor, but without using rare earth elements. Tokyo University of Science is developing an electric car that is the same size as a second generation Prius and uses absolutely no rare earth metals.”
The prototype is a modified 1999 Mazda MX5/Miata/Eunos powered by a 400V/9.5kWh hybrid switched reluctance motor. The lithium-battery consists of five modules that are sized at 215x335x210mm, with a total weight of 100kg each. Further work is needed to improve torque and energy efficiency – the aim is to achieve less than 5 per cent wasted energy – and reduce noise and vibration.