Fashionable as it might be to talk about critical metals in a world migrating towards a clean-energy future it is equally important to ask why some metals are considered critical and others not. TIM TREADGOLD reports
Critical, scarce or valuable?
Knowing what is genuinely critical in an economic sense, and not simply rare with limited economic value, could save industry from wasting time and money looking for metals which might not have a big future market.
The critical label applied to some metals can be confusing because scarcity could actually reflect a situation where demand is so small that there is little incentive to explore for more – but when the hunt does start the scarcity factor fades.
Lithium is a classic case of a metal which had a small market a few years ago when it was mainly used in making glass, ceramics and as a lubricant – and even as a medicine to treat bipolar disorder.
Lithium: an abundant but key metal in rechargeable battery technologies
Today, lithium is a key ingredient in rechargeable batteries of the sort used in electric vehicles with a rush into EVs initially sparking fear of a shortage – until explorers discovered that lithium is relatively abundant, it’s just that no-one was actively looking.
The net result is that while the future for lithium is bright a series of new mines in Australia and South America have filled the market and killed the price, with the result being the mothballing of newly-constructed projects before they could even start production.
Sorting out the facts from the popular understanding of what makes a metal important is a challenge currently under development as part of CSIRO's new portfolio of "missions" to better understand critical energy metals headed by CSIRO innovation and strategy leader, Dr Jerad Ford.
Metals for energy transition technology
"Our starting point is to focus on metals needed in the energy transition," Ford said.
"There are a lot of metals that have unique uses in exotic technologies such as night-vision goggles which means we could look at all sorts of minerals."
"But we see the number one critical-metals issue is ensuring sufficient supply to make a successful global energy transition. That means understanding exactly what metals will be required, and where they are going to come from."
The market for rare earth elements
Most newcomers to the issue of critical metals are influenced by the geopolitical debate around rare earths which, in simple terms, means China controls the market and other countries, especially the U.S., want them.
The debate has also been influenced by the publication two years ago of a U.S. Government list of 35 minerals which its Commerce Department deemed to be critical minerals and a similar list published five years ago by the British Geological Survey of 41 elements it believe could face future supply risk, largely because production is dominated by China.
The two lists are not identical but both have a number of common elements including rare earths which Ford said undoubtedly had a role to play in the development of new-energy technologies.
Copper and nickel global demand grows
But it is also important to consider the case for industrial metals such as copper and nickel because they are required in large quantities as the world switches to low carbon forms of energy.
Copper, which is used in everything electrical, is not often seen as being critical to a clean-energy future but without a substantial increase in supply it will be harder (and more expensive) to wean the world off fossil fuels.
The easiest example which explains the importance of copper is to consider the demand for the metal in an EV which is three-times that of a conventional petrol-powered car.
Explosive future demand projections make the case for criticality easy.
"Lithium is an obvious candidate for the critical designation, and right now the same can be said of cobalt," Ford said.
"But there are already questions being asked of cobalt as battery makers develop new products that do not require as much, if any, cobalt - particularly Lithium Iron Phosphate (LFP) batteries which are the choice of Battery Electric Vehicle (BEVs) manufacturers — as well as Tesla — in China we need to understand the way the market is changing."
"Copper is a safer bet because it is used in almost every clean-energy technology the world is looking at."
Indium in photovoltaics
Indium is another example of a metal topical today because of its uses in semi-conductors and photovoltaics which has triggered a number of exploration programs and the re-sampling of old drill cores, Ford said.
"But gross demand for indium is very small and there's also the question of whether projections of a sharp increase in future indium demand are correct."
While there could be strong growth for indium in next generation photovoltaics there will be greater demand for other metals, including silver, silicon and aluminium for silica-based photovoltaics which currently dominate the market.
"The focus of our research is to try and assess the level of metal demand in the global energy transition in the longer term, and determining exactly what metals will be needed," Ford said.
Balancing environmental cost of new metal production with low-emission energy generation
"Consuming more metals might have an environmental cost but there is more to gain in an environmental sense from the impact of new-energy technologies in reducing the need for fossil fuels in power generation and transport."
As far as the impact the "mission" is trying to make in the world, it's all about creating more value from our resources.
"We also want to identify where the best economic opportunities lie in higher-value manufacturing over the next five-to-10 years, areas such as metal alloys and precursors for batteries which will create jobs and long-term growth," Ford said.
Creating a critical energy-metals roadmap
"We're trying to create a critical energy-metals road map which will help identify the targets we need to aim for.
A better understanding of what makes a metal critical includes the development of a clearer picture of where those metals can be found and how they can be commercialised.
To this end, demand analysis and forecasting is part of the road map as is understanding the future sources of metal supply.
Ford said another of the aims of his mission was to identify how Australia could leverage some of its competitive advantages into creating future value from its critical metals.
Rare earths for example could theoretically be extracted from some types of iron ore as they could from the fly ash produced by burning coal.
In closing, Ford said the mission aims to be a flexible and a multi-year collaborative effort to help navigate these waters, and attract industry partners and funding to prove up technologies and help create new industries.