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In large part, this has to do with the expected rise in battery-powered electric vehicles, which represent 90% of battery demand growth; the other 10% will come from growth in stationary storage, used to balance out wind and solar on the grid.
If the world targets 2°C, minerals demand from energy storage will double from the baseline scenario; if the world targets 1.5°C, it will more than double again.
Batteries are composed of two electrodes, a cathode and an anode, and an electrolyte through which they exchange ions. Depending on what those three parts are made of, batteries require different minerals. Many EVs still use lead-acid batteries, which use lead and sulfuric acid, but lithium-ion batteries (LIBs) are expected to rapidly take over the market, so demand for lead-acid batteries won’t grow much.
LIB technology play bigger role coming decades
As for LIBs, most use graphite as the anode, which means graphite will be the most sought-after mineral in energy storage. Cathodes vary more widely. The most common use is nickel, with various mixes of cobalt, lithium and manganese also common.
It should be noted that these projections out to 2050 are to a large extent guesses, just an extension of the “average” LIB into the future. LIB technology could evolve in several different ways, and other storage technologies could play bigger roles in the coming decades.
“The assumption that lithium-ion batteries dominate both the mobile and stationary market for the next decade is conservative,” the World Bank writes. “Post-2030, the scale of uncertainty is much greater, with a wide range of options in both markets.”
Consider the options for LIBs. For cathodes, NMC111 batteries use one part nickel, one part manganese and one part cobalt, while newer NMC811 batteries use much more nickel and less cobalt. Tesla and other automakers are trying to eventually eliminate cobalt from their batteries; it’s too early to say how far they’ll get.
Right now, almost all anodes are graphite (a market dominated by China), but there is active development of zinc-air batteries that use air as the anode, sodium-ion batteries that use hard carbon as an anode and solid-state batteries (which replace a liquid electrolyte with a solid one) that use lithium as an anode. The mix of technologies that ultimately will triumph is still an open question, which means the precise trajectory of graphite demand is tough to predict.
If manufacturers seek to minimize cobalt, demand for nickel will rise. If solid-state batteries catch on, they could reduce the demand for graphite. If zinc-air batteries catch on, they could dent demand for lithium, graphite, nickel and manganese.
flow batteries become competitive in Post-2030
Post-2030, other storage technologies like flow batteries or a wide array of long-duration storage techs could become competitive. It depends on the evolution of policy and the electricity mix. It’s also worth noting that the practice of using second-life EV batteries as a form of grid storage could take off, which would trim the total demand for new batteries.
Finally, LIBs have made substantial advances in materials efficiency and those will likely continue, which could affect how sharply demand rises.
In terms of how geopolitically concentrated and environmentally destructive they are, the key minerals to watch here are graphite, nickel, lithium and cobalt, but it’s impossible to know their precise mix in advance.
Solar photovoltaics love aluminium and copper
Solar is another technology that we are confident is going to grow like mad in coming decades, but it’s difficult to predict the exact trajectory of minerals demand.
The World Bank paper looks at four common PV technologies: crystalline silicon (crystal Si), which makes up about 85% of the current market, and three different thin-film technologies that can be printed on flat sheets: copper indium gallium selenide (CIGS), cadmium telluride (CdTe) and amorphous silicon (amorphous Si).
All four are made primarily with aluminium, copper and silver, with different additional minerals contributing to different technologies. In terms of overall size, aluminium and copper are the biggies:
When it comes to copper, clean-energy technologies — batteries and solar, but also transmission and distribution systems — are the fastest-growing source of demand. In a 2-degree scenario, clean energy’s share of total copper demand will rise from today’s 24% to 45%. It’s going to drive a lot of new copper mining.
Demand for aluminium and copper will likely be robust no matter which way solar PV evolves, but for some minerals, the direction the technology takes has bigger consequences. For example, almost all (97%) of the indium used in the energy sector is for solar PV — specifically, thin-film solar PV.
Wind turbines are big on steel
Wind turbines are made mostly of steel for the turbines with lots of copper for cabling and iron for other parts. Most of those minerals are common in other clean-energy technologies. The one mineral for which wind is the primary source of demand is zinc; the wind would boost zinc demand at least 80%in a 2-degree scenario.
Most onshore wind farms use geared turbines, which “use a gearbox to convert the relatively low rotational speed of the turbine rotor (12–18 rpm) to a much higher speed (1,500 rpm) for input to a generator,” the World Bank writes. Around 80% of the current global wind capacity consists of geared turbines, attached to generators that use lots of iron and copper.
In direct-drive turbines, the generator is affixed to the rotor and turns at the same speed. These are more common in offshore installations, due to their lower maintenance requirements. They often use permanent magnets with rare earth elements.
The demand for some minerals will be greatly affected by the ultimate balance of onshore and offshore turbines, like neodymium, a rare earth element used only in permanent magnet direct-drive turbines. A 2-degree scenario in which offshore wind grows faster than expected could spike demand for neodymium by almost 50% relative to the base case; if onshore grows faster, it could sink neodymium demand by almost 70%