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Meet the robots plucking rare-earth metals from old iPhones.
In June 2021, a heat dome pulverized my hometown of Portland, Oregon, delivering an almost psychedelically high temperature of 116°F, killing 69 people, and smashing any illusions that the Pacific Northwest offered a relative haven from the scourge of a warming planet.
We now know that if Oregon hopes to avoid another heat dome, or if California hopes to dampen wildfires, or if Florida hopes to stanch the rise of coastal sea waters, we need to harness the elements of greener energy. Fortunately, some of the brightest scientific minds are striving to reap these elements from the grist of crisis.
Those earth-saving elements are literally that, elements. Lithium tops the list, along with cobalt, nickel, and manganese. Those four metals form the cathodes—the source of lithium ions—in lithium- ion batteries. Not far behind are the likes of tungsten, gold, and rare-earth metals.
These are all elements that power virtually every vehicle, device, and tool enlisted in the effort to decarbonize our lives, and in the long term, divert climate catastrophes.
But most of us have overlooked or missed that these foundational materials for so many green technologies currently come at a steep environmental cost. For example, with every pound of lithium that’s mined, 15 pounds of CO2 gets emitted in the process. In addition, most lithium battery factories run on coal power—which emits nearly twice the greenhouse gases of even natural gas—before the batteries are shipped halfway around the world.
To make our situation worse, the supply-chain snarls of the last three years have cut the stock of green components, especially lithium batteries, just as their demand is skyrocketing. By 2030, the market for lithium batteries is projected to increase by a factor of 5 to 10. This would be great news if we had enough lithium—or cobalt and other key elements—and less carbon-intensive methods for processing it.
“Daisy demonstrates that what many believe impossible really is possible.”
But there’s hope in the fact that these are elements, not compounds. Whether they’re coming from mined rocks, a first-gen EV, or a dead phone, they will always be lithium, cobalt, nickel, or manganese, and perpetually recyclable. If the cathode elements in a spent lithium battery can be effectively recaptured, they could be used to make new batteries and devices—not once, but ad infinitum and with greatly reduced emissions compared to ripping more from the ground.
Now here’s the good news: The technologies that would recycle those elements at scale, practically in our factories’ backyards, are already here, ready to be adapted for everything from electric toothbrushes to cars or wind turbines. Even better, lithium batteries are just one piece of the broader revolution. Several companies have spent the better part of the last decade developing new methods to recycle essential and rare-earth metals in a circular, closed-loop, sustainable supply that can help meet the burgeoning demand for electric cars and devices while drastically reducing their carbon footprints.
THE MASCOT Every new age has its defining symbol, the agent or entity expressing its character and reflecting its essence. For the new age of recycling, it may well be Daisy.
Daisy is a robot. Actually, Daisy is an amalgam of five separate robots, grouped into four modules that together stretch over 30 feet. She lives at Apple’s Material Recovery Lab in Austin, Texas. Her twin sister, also named Daisy, lives at an Apple facility in the Netherlands. Daisy is a disassembling robot, an imposing title for a delicate task: taking apart old iPhones, separating the battery along with other key elements and rare-earth metals—the next frontier for recycling after batteries—and distributing each piece into bins for recycling into new devices manufactured by Apple and other companies. Daisy plays a major role, part tangible, part symbolic, in Apple’s ambitious campaign to manufacture all its products with 100 percent recycled or renewable materials. “Daisy demonstrates that what many believe impossible really is possible,” says Sarah Chandler, senior director for environment and supply-chain innovation at the company.
When work on Apple’s disassembling project began in 2012, industrial-age techniques employed by Apple and other companies were relatively crude. Machines smashed the incoming material into chunks no smaller than an inch, which were too impure to reuse in newer devices.
In 2014, engineers developed Liam, Daisy’s grandfather, a pilot-project robot capable of disassembling just one device, the iPhone 5. “Liam started the journey of innovation, proving the validity of setting big goals,” Chandler says.
However, Liam needed 12 minutes to take apart one used phone, while Apple was selling more than 3,800 phones worldwide every 12 minutes. A few years later, Liam 2.0 could process an iPhone 6 at a faster clip. And Daisy, introduced in 2018, can disassemble 23 models of iPhone at a rate of 3.3 per minute, a level of performance unequaled by any device-recycling machine in the world. Hitting this mark required the efforts of some of Apple’s best engineers and designers.
“Engineers know a lot about using robots for manufacturing a product, when the materials are fresh and uniform, and can be measured and meted in an ordered, predictable fashion,” explains Chandler. “But recycling presented a whole new challenge: How do you design a robot to function under conditions that are the opposite of ordered and predictable?”
Daisy is expected to recognize and efficiently disassemble nearly two dozen different devices, with each phone arriving at the recovery lab battered and spent in its own singular way. Designers couldn’t merely reverse-engineer the manufacturing process; they had to create a machine capable of intelligent functioning, adapting to every phone coming into Daisy’s grip, each with its own unique scars and quirks. “You could almost think of the Daisy project as a work of art,” Chandler told me. “A robot capable of beautiful deconstruction.”
First, an incoming device approaches on a conveyor belt, where Daisy’s robotic eye determines the vintage of her iPhone prey. Then, she pulls off the phone’s screen with her robotic arm. Next, a punch of freezing air loosens the phone’s battery from its enclosure. The spent lithium battery drops onto the belt like a ripe pear from its tree.
Then comes screw removal. For Liam, engineers employed a screwdriver device to carefully and delicately remove each screw. To save time, Daisy instead punches loose the screws with a satisfying thump.
By the final step, the old iPhone is reduced to hundreds of tiny, shiny bits containing aluminum, cobalt, copper, glass, gold, lithium, steel, tin, tungsten, zinc, and other metals and rare-earth elements, which are put into bins to be sent out for further processing. Eventually, these bits will enter the industry’s general upstream supply chain. But a portion of the recycled material may land at another Apple facility to be woven back into a new Apple product. In the best of possible worlds, the iPhones whose parts have traveled through Daisy will return to her later for another round of beautiful deconstruction.
But of course, we’re not yet living in that world. And many cellphones and similar devices don’t get recycled at all: “A fortune’s worth of cathode materials are sitting unused in Americans’ drawers,” says Michael O’Kronley, CEO of the lithium-battery recycling company Ascend Elements.
Apple acknowledges this situation. “Daisy’s hungry,” Chandler says. “And we’ve opened free recycling programs in every country where we sell iPhones.” She also offers the Material Recovery Lab as an example to be emulated across industries. Most of the innovative work performed at the lab is open-sourced; Daisy has earned five patents, but Apple licenses the robot’s technology to other parties for free. In the years ahead, pieces of Daisy may appear in recyclers all over the world. “Daisy has taught us so much,” Chandler says. “Now let’s partner, change the industry, and share with everyone.”
BLACK GOLD “It was just a matter of time,” Yan Wang remembers thinking. The year was 2011. Wang was a chemical engineer and newly hired professor at Worcester Polytechnic Institute in Massachusetts, and lithium-ion batteries were already everywhere—in phones and laptops, solar panels and wind turbines, electric hedge trimmers, and baby monitors. Early-edition electric vehicles, the Leafs and Volts, glided down American highways, and paradigm-shifting plans were afoot for electrifying the grid.
All of these vehicles and tools, all of this projected infrastructure, ran on lithium batteries. At scientific conferences Wang attended, the buzz was all about making those batteries more powerful, boosting the juice necessary to drive the EVs and extending the time before recharging. Few were considering the end-of-life issue: what to do when all those batteries needed replacing.
“At the conferences, if your topic was end-of-life, you would be the last speaker of the day,” says Eric Gratz, Wang’s former student and present business partner. “People started slipping out of the room when you took the podium.”
“A fortune’s worth of cathode materials are sitting unused in Americans’ drawers.”
Wang couldn’t predict all that would happen over the next 10 years to threaten access to cathode materials. But he did know a few key facts: All lithium batteries eventually wear out—typically within three years for a phone, and five to 10 for an EV; nearly two-thirds of the processing of cathode materials takes place in China; and when EV batteries start to fade in coming years, their toxic materials would pile up in landfills, creating more environmental problems than they solved.
A decade ago, sitting in the audience of those scientific conferences, Wang envisioned lithium battery recycling as an efficient, even elegant, way to meet the looming challenges, and a model for a green and prosperous circular economy, and a way for a fledgling professor to make a name for himself.
“Sooner or later, people would see the big promise in lithium battery recycling,” Wang remembers thinking. “It was just a matter of time.”
At that point, the cost of recycling lithium batteries was prohibitive. The traditional methods that had been in practice for decades did an imperfect job of separating the elements: Pyrometallurgy burns or smelts the shredded material with intense heat. And hydrometallurgy treats the material with water and chemicals. Moreover, the material recaptured by these techniques had to be shipped to China for processing, then on to a battery manufacturer in China or elsewhere in Asia, before arriving at a facility in North America, Europe, or other place around the globe to be built into a new product. “The process was wasteful and expensive,” Wang told me, “and left a large carbon footprint.” It was cheaper for manufacturers to use virgin materials, although their extraction presented their own environmental problems.
Wang and his team began searching for a better way. “It’s not easy to bring research to scale,” he says. “It’s one thing for an experiment to work in the lab, but another to make it viable for industry.”
With a practical application in mind, Wang focused on the materials that make up the cathode, the part of the battery responsible for its capacity and power, and presents the highest commercial value (when a battery is powering a device, lithium ions move from the anode, a negative electrode, through an electrolyte solution to the cathode, a positive electrode; when the battery is charging, the order is reversed). After traditional recycling methods burned or dissolved lithium, cobalt, nickel, and manganese, they emerged similar in weight and appearance, and difficult and costly to separate. Wang’s big insight was to keep the materials together, remove the impurities, and create a new product.
Wang devised a method called Hydro to Cathode that could take a 10-year-old battery from a first-generation EV, process it into an aqueous solution containing lithium, cobalt, and nickel atoms, then create new cathode-active material. The process could recover 98 percent of essential battery metals, and produce the new cathode material at half the cost and a 90 percent reduction in greenhouse emissions compared to a cathode made from newly mined elements.
The result was a crystalline mass of black cathode powder: “black gold,” in the parlance of Wang’s new company, Ascend Elements. Wang’s next step was to add a dollop of virgin material to the mass—according to the specs of the customer. A lithium–cobalt oxide battery going into a phone differs in composition from a lithium-nickel-cobalt– aluminum oxide battery going into an EV. The powder is then pasted on a metal strip to be placed in a new battery. “A lot of companies recycle, but we transform the material into something better,” Ascend’s O’Kronley told me. “It’s a kind of alchemy.”
Ascend and other players in the nascent battery-recycling industry are confronting the bias against using recycled materials in new products. Battery manufacturers worry that recycled minerals are of lower quality than mined ones, leading to shorter battery life and other deficiencies. Research published in the journal Joule in 2021, however, showed the opposite: Batteries containing materials derived from Ascend’s Hydro-to-Cathode technology delivered 88 percent more power than those composed of virgin materials, and demonstrated a 50 percent longer cycle life. Researchers, led by Wang, concluded that the rebuilt powder particles are more porous, allowing the cathode crystals to swell as lithium ions pass through them. The increased space and surface area prevents the crystals from cracking, and allows the recycled- element batteries to charge faster.
Ascend’s technology quickly drew interest from investors and industry, and the company grew from a 300-square-foot space in 2015 to a privately held corporation that raised more than $90 million in capital investment in 2021. When it opens later this year, Ascend’s new 154,000-square-foot facility in Georgia will be the largest lithium-battery recycling plant in the U.S. Wang and Gratz no longer bat last at scientific conferences, and Ascend competes with a range of companies in the recycling industry. Two of its biggest competitors are Redwood Materials, a Nevada-based company founded by JB Straubel, the cofounder and former CTO of Tesla, and Li-Cycle. Together, they service a market worth an estimated $18 billion annually, up from $1.5 billion in 2019. Over the next 10 years the demand for lithium batteries is projected to grow up to tenfold.
During that decade, Wang predicts that the industry’s main players will all be kept busy. “The typical passenger EV contains around 1,000 pounds of battery. All the batteries in the first generation of EVs are going to need replacing about the same time,” he says. Only a fraction of the demand for new batteries will be met through recycling, but that percentage will grow as the technology improves, more cathode material becomes available, and the cost of recycling goes down. Ascend has partnered with Honda’s American subsidiary and other automakers to retool their spent batteries, and Redwood Materials has a similar deal with Panasonic, which supplies Tesla.
“The typical EV contains around 1,000 pounds of battery. All the batteries in the first generation of EVs are going to need replacing about the same time.”
Currently, however, the principal source of the material that hits recycling floors is scrap—unused or discarded material from the factories that manufacture lithium batteries. That’s why Redwood Materials has built its main facility in Carson City, Nevada, close to the Panasonic gigafactory that supplies Tesla, and Ascend located its plant in Georgia, close to a massive SK Innovation battery factory. When the Ascend plant is fully operational, truckloads of scrap will go from the SK Innovation facility to Ascend, and truckloads of reconstituted cathode material will go from Ascend to SK Innovation. It’s a virtual case study for a closed-loop, circular economy. For now, spent batteries are number two in the recycling industry’s food chain, but in the years ahead they will rocket to number one.
Meanwhile, the public sector is sending belated but welcome reinforcements. The Biden administration’s infrastructure act dedicated $60 million to battery recycling. The Department of Energy (DOE) funds the ReCell Center at Argonne National Laboratory, with the goal of developing a cost-effective process for recycling lithium batteries within three years. Born during World War II and a center for the fabled Manhattan Project, Argonne’s scientists developed the last conceptual leap in renewable energy: nuclear power. In the years ahead, lithium battery recycling may prove to be the next revolutionary breakthrough.
THE CHEMIST Megan O'Connor wasn’t exactly barred from sitting in at the closed-door meeting, but she wasn’t invited, either. In 2015, O’Connor was a 25-year-old graduate student in environmental engineering at Duke University, attending a green-electronics summit at Yale. After the regular session ended, the conference’s featured speakers privately convened. O’Connor negotiated her way into the room by agreeing to be the scribe, took a seat at the back, and listened to the talk about electric vehicles, cathode-material supply chains, and the looming EV-battery tsunami.
The tone was hopeful. A circular economy based on recycling the components in lithium batteries made environmental, economic, ethical, and political sense. Much of the nickel and lithium needed for electrifying the grid using renewable energy was already in circulation. With the right technology, those elements could be recycled endlessly.
The promised land still lay at a considerable distance, but O’Connor, who fell in love with chemistry while growing up in Plattsburgh, New York, thought blending her passions for science and the environment might point to a trailhead. She returned to Duke from the summit determined to find her own way to contribute. A second pivotal moment soon followed, when she listened to a presentation by Chad Vecitis, a Harvard professor of environmental engineering.
“Chad was describing his experiment using what was basically a kitchen-size Brita water filter to treat and clean wastewater,” O’Connor told me. “He achieved impressive results by running an electric current through the water.”
O’Connor, working with her PhD advisor, Desirée Plata, wondered: Why couldn’t the same method be used to separate recycled metals? She immediately changed her research focus to explore this question. Collaborating with Vecitis, who had already worked out the basic science of the process, O’Connor successfully devised a method for electroextraction. Instead of the hydro recycling method that uses potent chemicals, or the pyro method with its furnaces—both of which are also carbon-intensive—O’Connor’s system used renewable electricity to separate the lithium, cobalt, nickel, and manganese produced from shredded battery material.
Combining electricity with water filtration, the process employed a basic carbon water filter, much like one in a swimming pool. After shredding and further processing steps, an aqueous solution containing the cathode material is pushed through the filter. Then, an electric current of varying voltage is applied, selectively separating the metals, which fall to the bottom of the filter.
Similar to Wang, O’Connor sought practical, industrial applications for her research. While Wang envisioned a business model based on large-scale battery recycling, however, O’Connor thought small. “Starting with the idea of a kitchen-size water filter, my approach was always small, agile, and flexible,” O’Connor says. “Electroextraction has the potential for disrupting the industry, but our technology complements the big companies rather than competing with them.”
O’Connor’s system had several advantages, the first being that “we could go where the batteries are,” she says. Instead of transporting the used batteries or other e-waste to a central location, O’Connor’s technology could operate on-site at regional recycling facilities, using off-the-shelf carbon filters modified to pick out cobalt, nickel, and other high-value materials. All the gear was compactly housed in a 1,000-square-foot module that was run by two operators.
O’Connor’s timing was propitious. By the mid-2010s, the momentum toward EVs, lithium batteries, and the electrification of the grid was starting to build. Green-energy startups were sprouting throughout the developed world, and investors eagerly followed. The day after she defended her doctoral thesis in 2017, O’Connor, Plata, and Vecitis cofounded Nth Cycle, a metals processing company that uses electroextraction technology to recapture a range of metals and materials in both the recycling and mining industries. Early support came from DOE and National Science Foundation funding. In 2021, the company raised $12.5 million in private financing.
While announcing his company’s investment, VoLo Earth cofounder and managing partner Joseph Goodman said, “There is simply no way we will achieve the urgent goals of electrification and decarbonization without widespread deployment of technologies like Nth Cycle’s to improve the economics and environmental impact of how we extract critical minerals.”
The company plans to start deploying its modules to facilities this year. O’Connor is initially targeting midsize regional centers that collect used batteries. “But our technology could add value to a facility of any scope or size,” she told me. “I could even see us working with Apple. For instance, after Daisy distributes the recaptured material into various bins, our modules could help define and refine the materials.”
Whether or not Nth Cycle and electroextraction technology find a place in Apple’s Material Recovery Lab, O’Connor, who earned a spot in the prestigious Forbes 30 Under 30 list for 2019, stands as a model for the young scientists and engineers whom the lab seeks to inspire. “The young engineers with new ideas, the entrepreneurs with their startups, play a critical role,” says Ascend CEO O’Kronley. “Not all the startups will survive, and not all the technologies will prove viable, but to meet this challenge—to establish and maintain a sustainable, reliable supply chain for the critical materials we’ll need for a green circular economy—we need all sorts of ideas from all kinds of people.”
O’Connor, for her part, marvels at how far she has come since she talked her way into that closed-door meeting at Yale in 2015. “Once you move out of the lab and start running a business, you’re supposed to get a little jaded. I feel the opposite,” she says. “I’m more excited now than when I was that grad student, or even that teenaged kid who fell in love with chemistry.” Like the cathode-reimagining, potentially heat-dome-snuffing industry that Megan O’Connor serves, she knows she is just beginning.
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