The invisible device that powers everything you do

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The Nobel Prize for chemistry was announced earlier this month: three scientists shared the almost $1 million award for their work on how cells repair DNA.

Once again it did not go to John Goodenough, the 93-year-old physicist regarded as the father of the lithium ion battery. You probably haven’t heard of him, but for years, pundits have predicted that Goodenough would win science’s highest honor. And for good reason. His work transformed society. His is possibly the most revolutionary invention yet not to win the prize. What’s it to you? Well, your life wouldn’t be the same without his work.

The phone (or laptop) you’re reading this on wouldn’t exist without lithium-ion batteries. Selfies, Snapchat, fitness tracking, and hoverboards wouldn’t be possible in their absence. They’ve allowed us to explore the Moon, Mars and other celestial bodies by providing the juice that keeps Mars rovers, space suits and satellites running. They power the devices that help sickly hearts pump blood and that magnify sound for people who can’t hear well. They’re in, on and around us all the time. Just today, you’ve probably encountered dozens of lithium-ion powered appliances and you didn’t even know it.

“The revolution in portable consumer electronics has only been possible because of the lithium battery,” Paul Shearing, a chemical engineer at University College London, told me. It’s the forgotten hero of the mobile era. The silicon brains inside our phones, tablets and laptops often get all the credit for enabling the tech-infused world we live in, but without lithium-ion batteries these machines would be too heavy to carry, and they’d poop out too quickly, leaving us stranded when we need them most.

And this is just the beginning of the lithium battery’s world-changing potential. “Its second big contribution— the bulk of which is yet to come—will be the electric vehicle,” said Jason Graetz, the manager of HRL’s sensors and materials laboratory in Malibu, California.

Electric cars and hybrids are just starting to gain popularity, helping to wean us slowly from emissions-spewing cars which cost the average household $2,500 in gas per year. But they’re still too expensive for most. So, 35 years after he developed the crucial component upon which every lithium-ion battery is built, Goodenough thinks he may have a way to build a better, cheaper, more powerful battery that could one day power our cars.

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When John Goodenough returned home from World War II,  he “had this feeling one ought to do something to bring all the people of the world together,” he told me. “War is stupid.”

The then-24-year-old U.S. Army captain started studying physics at the University of Chicago. As a child, he couldn’t read well, and he struggled through school. (He was dyslexic.) But he’d always had a knack for math, and physics is math applied to real-world problems. After earning his PhD in 1952, he ended up at MIT where he worked on making computer memory faster and more reliable.

In the late 60s, the country became enthralled with the idea of an electric car after Ford, the company that popularized the combustion-engine vehicle, talked openly about developing a battery-powered one. Then in 1973 came the Arab oil crisis. Together, these sparked interest in batteries among scientists and the public alike.

At their most basic, batteries are devices that shuttle ions, or charged atoms, from point A to point B. When ions move, they create an electric current, which you can harness to power a device. Ions start out at a battery’s negative end, called the anode, and then move to its positive end, called the cathode, when a gadget is on. Sandwiched in between the anode and cathode is the electrolyte, the substance through which these ions move. That’s the basic anatomy of a battery. What each of these components is made of affects how good a battery is, and how long it lasts.

By the 70s, Goodenough had made his mark developing various technologies that would change the computing industry, namely magnetic-core memory, a form of data storage that was much more reliable than the bulky tubes that preceded it. What he really wanted to do was tackle our dependence on fossil fuels. The U.S. Department of Energy actually tapped Goodenough to monitor battery research at Ford in 1973. But then came the Mansfield Amendment, a piece of legislation that prohibited Air Force-funded labs to do any research that wasn’t directly applicable to the military missions. At that point, lithium-ion batteries weren’t, and Goodenough’s MIT lab was bankrolled by the Air Force.

Goodenough wanted to keep doing basic research, so his adventures in battery-making took him to Oxford. It was there that he invented the so-called lithium-cobalt-oxide cathode, the heart of the modern lithium ion battery. He wasn’t the first to turn to lithium, but Goodenough was the first to use it in the right combination with other molecules to pave the way for a rechargeable battery that could produce a lot of power but that wouldn’t readily explode or die too quickly.

Scientists already knew that lithium could transmit a lot of power, and that it was light and compact—qualities that made it attractive as a battery component. One of Goodenough’s contributions was figuring out just how much the battery’s lithium ions could shuttle back and forth before a battery stopped working, given a particular voltage. (In a battery, the higher the voltage, the more energy you can squeeze out of it do the work you need done.) This is a Goldilocks problem. Too little, and the battery wouldn’t be all that useful because not enough current would be generated. Too much, and the cathode would collapse in on itself, killing the battery. The magic amount was about 50%, at around four volts, higher than previous prototypes of rechargeable lithium batteries.

But Goodenough’s big trick was metal oxides, compounds that contain oxygen and some metal element. Goodenough had worked with these compounds while he was trying to build better memory for computers back at MIT. In a battery, metal oxides are like parking lots designed for easy entry and exit. That’s really important because how well a battery is able to power a device depends on how quickly ions, in this case lithium, can travel back and forth between the negative and positive terminals. If the metal oxide “slots” are always in the same place, perfectly spaced out, lithium can come in and out quickly. If they become crooked over time, efficiency drops. That’s where cobalt comes in. Of all the metals Goodenough’s lab tested, cobalt provided the most stability, and so the lithium-cobalt-oxide cathode was born in 1980.

It was revolutionary because unlike past batteries it worked well in both small and large appliances. Sony would use it 11 years later to build the first rechargeable mass-market lithium-ion batteries. They allowed video cameras to morph from beastly contraptions into handheld devices. Before lithium-ion came along, nickel cadmium batteries were the standard, but these were quite large, and added unnecessary bulk to consumer electronics.

By the mid-90s, almost all videocameras with rechargeable batteries were running on lithium ion. It enabled the miniaturization of devices across industries. Quickly, they made their way into laptops and cellphones, and then eventually into tablets, power tools, and medical and mobile devices.

“It has become the largest battery chemistry in terms of the number of cells sold, capacity and revenue,” said Sam Jaffe, an industry analyst with Cairn Energy Research Advisors. “It has quickly taken over the world. We expect it to be the dominant chemistry going forward through the next decade.”

By 2020, the lithium battery market could be worth a whopping $75 billion, he says. As lithium ion batteries make their way into the energy sector, Jaffe thinks they’ll “become the foundation of the global economy.”

So far, lithium’s global reach has achieved one of Goodenough’s goals. “I’m very happy,” he said, because the technology “has been very beneficial to the poor and to the rich, helping to bring the world together.” For instance, mobile internet access jumped from 18 percent in 2011 to 36 percent today, according to the Boston Consulting Group. By 2017, it’s expected to reach 54%, surpassing fixed-line access. Mobile devices, our doorway to the internet, are powered mostly, if not exclusively, by lithium-ion batteries.

His other aim, to kill the combustion engine, still eludes him, 24 years after the lithium revolution began.

In tech, we’re used to fast, sweeping change. Techies often reference Moore’s law as the phenomenon that’s made our devices cheaper, smaller, more powerful, and portable. It’s true that every two years, the number of transistors, the building blocks of a modern computer, doubles on a chip. Over roughly five decades, that exponential growth has allowed companies to squeeze as much computing power into your smartphone as used to require a behemoth, room-sized machine.

For batteries, the improvements have been more incremental, below 10% per year in terms of energy density, the total energy that can be stored in a given volume, according to Graetz, the manager of HRL’s sensors and materials laboratory in Malibu, California. That’s held back the mass market availability of electric cars, even as batteries for other mobile devices, like phones, tablets and laptops have gotten smaller, cheaper and more powerful. Lithium-ion batteries have helped unleash multi-billion dollar industries, but the endgame for Goodenough, who’s now at the University of Texas at Austin, has always been the electric car.

“I’ve always been concerned about the environment of course,” he said. As climate change has become more of a pressing issue, society has caught up.

“Our main target is the electric vehicle,” said Ping Liu, the program director for the Department of Energy’s research arm, which is investing heavily in battery research. “But with cars, two things determine your fate. How much you pay, and how far you can go.”

Right now, Teslas are the electric cars with the most name recognition and arguably the best technology. But their range per charge hasn’t quite hit the 300-mile target, the distance experts quote as the minimum necessary to make electric vehicles convenient.

They also cost upwards of $70,000. The newly released SUV starts at $80,000. Most people can’t afford that, so the company has plans to sell a cheaper model with a price tag of about $30,000, slightly below the average cost of a car in the U.S. That will require cheaper batteries, since the battery is the most expensive part of an electric vehicle. Tesla’s Gigafactory, a solar- and wind-energy powered facility to manufacture lithium-ion batteries, should help bring the cost down, but the economies of scale can only take us so far. (Tesla could not accommodate our request for an interview.)

Teslas have been called smartphones on wheels. But at a battery level, smartphones and cars are very different. To power your energy-hungry smartphone, the manufacturer can crank up the voltage at which the battery operates to squeeze more juice out of it. But doing that shortens the battery life. For gadgets we chuck after two years that approach works just fine. But cars are longer-term investments.

So they need a battery that not only lasts many years, but that also packs a lot of energy and recharges quickly and is light and cheap and safe. Those are tremendous constraints, and battery chemistry is complicated. Unlike Moore’s law, it’s not just about stuffing more into less space.

“That’s mentally straight-forward,” said Jeff Dahn, a lithium battery expert who will be working with Tesla starting next year. “In a lithium battery, we’re really limited by the Periodic Table in the materials we can use.”

To make a good battery, you need components that are lightweight, plus fast and efficient at carrying charge. Plus, they need to be abundant enough to be cheap. Only a few elements on the periodic table satisfy those criteria. Lithium is like the Usain Bolt of ions. It’s the lightest metal on the periodic table; it carries charge well; and it can shuttle between a battery’s positive and negative poles very quickly. That last point, called “cycling,” is important because it’s what determines a battery’s output. In a car, the faster a battery “cycles,” the faster you can accelerate, for instance. Earth’s lithium stores are also plentiful, according to Jaffe, the industry analyst. All this makes lithium an ideal battery material.

But cobalt, the other crucial component in today’s lithium-ion batteries, is expensive. Because of that, battery scientists have played around with other cathode recipes that include cheaper metals like nickel, manganese, and iron, with some success. (Goodenough championed the switch to some of these alternative cathodes, experts told me.) Still, these other metals haven’t displaced cobalt completely. The best batteries around have cathodes made up of some combination of nickel, manganese and cobalt. Tesla uses nickel-manganese-cobalt oxide batteries. These are the dominant type in electric vehicles, Dahn said. They cross off two very important points on the “EV Dream Battery” checklist: they’re safer and they have a longer shelf-life than other batteries on the market.

But they have one significant drawback: the amount of energy they pack isn’t great, which means you need a bigger battery to get you the distance you need to go. That drives up the cost and weight, which limits the range of electric vehicles today, both on the road and in the market.

One of the alternatives would be to go pure lithium metal. “You can think of the anode and cathode as lithium hosts. The more you can stuff in there, the more energy that’s packed in there,” said HRL’s Graetz. “The best energy density would be pure lithium metal itself for the anode.”

If scientists like Goodenough could get this to work, lithium batteries would have at least three to five times the energy density than the best ones available today. “We understand the limits of the chemistry,” Graetz said, “but making it a practical system is a challenge.”

Solving that could finally give electric cars their cellphone moment, thrusting them into the mainstream.

Goodenough and his team are working on a system that might allow battery engineers to use a solid lithium anode safely. The team is still in the process of testing out how well it works in a fully operational battery. Its defining moment will be whether it can be incorporated into a long-lasting battery, one with a life-time longer than the ones currently available and that is more powerful.

“We need to do that before we make any big shout,” he told me. “We’re not making a big announcement that we’ve solved all the energy problems of the world, but if we could get the electric vehicle to compete with the combustion engine, we will have made a big contribution.”

If Goodenough’s new research pans out, it could do that, and more. A more efficient battery would turbocharge the still fledgling energy storage industry, allowing us to save up energy we collect from solar panels and wind farms for later use much more efficiently than is currently possible. Some worry that the accumulation of batteries will also have unforeseen environmental consequences. Longer-lasting lithium batteries wouldn’t completely solve that problem, but it would diminish the number of replacement batteries we’d need to manufacture.

Which means the next car we can afford to lease or buy might very well be electric. And maybe Goodenough will finally get his Nobel Prize.

Daniela Hernandez is a senior writer at Fusion. She likes science, robots, pugs, and coffee.

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