Lighthouse Eco

Striving for a sustainable Lifestyle

Electric Vehicles Energy Renewable Energy

Electric cars and batteries: how will the world produce enough?

Reducing the use of scarce metals — and recycling them — will be key to the world’s transition to electric vehicles.

The age of the electric car is upon us. Earlier this year, the US automobile giant General Motors announced that it aims to stop selling petrol-powered and diesel models by 2035. Audi, based in Germany, plans to stop producing such vehicles by 2033. Many other automotive multinationals have issued similar road maps. Suddenly, major carmakers’ foot-dragging on electrifying their fleets is turning into a rush for the exit.

The electrification of personal mobility is picking up speed in a way that even its most ardent proponents might not have dreamt of just a few years ago. In many countries, government mandates will accelerate change. But even without new policies or regulations, half of global passenger-vehicle sales in 2035 will be electric, according to the BloombergNEF (BNEF) consultancy in London.

This massive industrial conversion marks a “shift from a fuel-intensive to a material-intensive energy system”, declared the International Energy Agency (IEA) in May. In the coming decades, hundreds of millions of vehicles will hit the roads, carrying massive batteries inside them (see ‘Going electric’). And each of those batteries will contain tens of kilograms of materials that have yet to be mined.

Anticipating a world dominated by electric vehicles, materials scientists are working on two big challenges. One is how to cut down on the metals in batteries that are scarce, expensive, or problematic because their mining carries harsh environmental and social costs. Another is to improve battery recycling, so that the valuable metals in spent car batteries can be efficiently reused. “Recycling will play a key role in the mix,” says Kwasi Ampofo, a mining engineer who is the lead analyst on metals and mining at BNEF.

Battery- and carmakers are already spending billions of dollars on reducing the costs of manufacturing and recycling electric-vehicle (EV) batteries — spurred in part by government incentives and the expectation of forthcoming regulations. National research funders have also founded centres to study better ways to make and recycle batteries. Because it is still less expensive, in most instances, to mine metals than to recycle them, a key goal is to develop processes to recover valuable metals cheaply enough to compete with freshly mined ones. “The biggest talker is money,” says Jeffrey Spangenberger, a chemical engineer at Argonne National Laboratory in Lemont, Illinois, who manages a US federally funded lithium-ion battery-recycling initiative, called ReCell.

Related posts:

Lithium future

The first challenge for researchers is to reduce the amounts of metals that need to be mined for EV batteries. Amounts vary depending on the battery type and model of vehicle, but a single car lithium-ion battery pack (of a type known as NMC532) could contain around 8 kg of lithium, 35 kg of nickel, 20 kg of manganese and 14 kg of cobalt, according to figures from Argonne National Laboratory.

Analysts don’t anticipate a move away from lithium-ion batteries any time soon: their cost has plummeted so dramatically that they are likely to be the dominant technology for the foreseeable future. They are now 30 times cheaper than when they first entered the market as small, portable batteries in the early 1990s, even as their performance has improved. BNEF projects that the cost of a lithium-ion EV battery pack will fall below US$100 per kilowatt-hour by 2023, or roughly 20% lower than today (see ‘Plummeting costs of batteries’). As a result, electric cars — which are still more expensive than conventional ones — should reach price parity by the mid-2020s. (By some estimates, electric cars are already cheaper than petrol vehicles over their lifetimes, thanks to being less expensive to power and maintain.)

Salt deposits in a lithium production facility at the Uyuni salt flats in Potosi, Bolivia.
Credit: Carlos Becerra/Bloomberg/Getty

Managing metals

To address the issues with raw materials, a number of laboratories have been experimenting with low-cobalt or cobalt-free cathodes. But cathode materials must be carefully designed so that their crystal structures don’t break up, even if more than half the lithium ions are removed during charging. And abandoning cobalt altogether often lowers a battery’s energy density, says materials scientist Arumugam Manthiram at the University of Texas in Austin, because it alters the cathode’s crystal structure and how tightly it can bind lithium.

Manthiram is among the researchers who have solved that problem — at least in the lab — by showing that cobalt can be eliminated from cathodes without compromising performance. “The cobalt-free material we reported has the same crystal structure as lithium cobalt oxide, and therefore the same energy density,” or even better, says Manthiram. His team did this by fine-tuning the way in which cathodes are produced and adding small quantities of other metals — while retaining the cathode’s cobalt-oxide crystal structure. Manthiram says it should be straightforward to adopt this process in existing factories, and has founded a start-up firm called TexPower to try to bring it to market within the next two years. Other labs around the world are working on cobalt-free batteries: in particular, the pioneering EV maker Tesla, based in Palo Alto, California, has said it plans to eliminate the metal from its batteries in the next few years.

Sun Yang-Kook at Hanyang University in Seoul, South Korea, is another materials scientist who has achieved similar performance in cobalt-free cathodes. Sun says that some technical problems might remain in creating the new cathodes, because the process relies on refining nickel-rich ores, which can require expensive pure-oxygen atmospheres. But many researchers now consider the cobalt problem essentially solved. Manthiram and Sun “have shown that you can make really good materials without cobalt and [that] perform really well”, says Jeff Dahn, a chemist at Dalhousie University in Halifax, Canada.

A woman and a man separating cobalt from mud and rocks by a river in the Democratic Republic of Congo
Workers extract cobalt near a mine between Lubumbashi and Kolwezi, in the Democratic Republic of the Congo.
Credit: Federico Scoppa/AFP/Getty

Recycle better

If batteries are to be made without cobalt, researchers will face an unintended consequence. The metal is the main factor that makes recycling batteries economical, because other materials, especially lithium, are currently cheaper to mine than to recycle.

In a typical recycling plant, batteries are first shredded, which turns cells into a powdered mixture of all the materials used. That mix is then broken down into its elemental constituents, either by liquefying it in a smelter (pyrometallurgy) or by dissolving it in acid (hydrometallurgy). Finally, metals are precipitated out of solution as salts.

An electric car battery module entering a battery shredder with powerful metal teeth
A mechanical shredder grinds up battery modules, here shown at the Duesenfeld recycling plant in Germany.
Credit: Wolfram Schroll/Duesenfeld

Research efforts have focused on improving the process to make recycled lithium economically attractive. The vast majority of lithium-ion batteries are produced in China, Japan and South Korea; accordingly, recycling capabilities are growing fastest there. For example, Foshan-based Guangdong Brunp — a subsidiary of CATL, China’s largest maker of lithium-ion cells — can recycle 120,000 tonnes of batteries per year, according to a spokesperson. That’s the equivalent of what would be used in more than 200,000 cars, and the firm is able to recover most of the lithium, cobalt and nickel. Government policies are helping to encourage this: China already has financial and regulatory incentives for battery companies that source materials from recycling firms instead of importing freshly mined ones, says Hans Eric Melin, managing director of Circular Energy Storage, a consulting company in London.

The European Commission has proposed strict battery-recycling requirements which could be phased in from 2023 — although prospects for the bloc to develop a domestic recycling industry are uncertain. The administration of US President Joe Biden, meanwhile, wants to spend billions of dollars to foster a domestic EV battery-manufacturing industry and support recycling, but hasn’t yet proposed regulations beyond existing legislation classing batteries as hazardous waste that must be safely disposed of. Some North American start-up firms say they can already recover the majority of a battery’s metals, including lithium, at costs that are competitive with those of mining them, although analysts say that, at this stage, the overall economics are only advantageous because of the cobalt.

Another report from the IEA, an organization noted for its historically cautious forecasts, included a road map to achieve global net-zero emissions by mid-century, which includes conversion to electric transport as a cornerstone. The confidence that this is achievable reflects a growing consensus among policymakers, researchers and manufacturers that challenges to electrifying cars are now entirely solvable — and that if we want to have any hope of keeping climate change to a manageable level, there is no time to lose.

But some researchers complain that electric vehicles seem to be held to an impossible standard in terms of the environmental impact of their batteries. “It would be unfortunate and counterproductive to discard a good solution by insisting on a perfect solution,” says Kamath. “That does not mean, of course, that we should not work aggressively on the battery disposal question.”



Davide Castelvecchi at Nature

Related Images:

Leave a Reply