Nobel in chemistry honours work on lithium-ion batteries
The Royal Swedish Academy of Sciences on Wednesday awarded the 2019 Nobel Prize in chemistry to three scientists who developed lithium-ion batteries, which have revolutionized portable electronics and are very likely powering a device you’re using now to read this article. Larger examples of the batteries have given rise to electric cars that can be driven on long trips, while the miniaturized versions are used in lifesaving medical devices like cardiac defibrillators.
John B. Goodenough, M. Stanley Whittingham and Akira Yoshino will share the prize, which is worth about $900,000.
“Lithium-ion batteries are a great example of how chemistry can transform peoples’ lives,” said Bonnie Charpentier, president of the American Chemical Society. “It’s wonderful to see this work recognized by the Nobel Prize.”
The three researchers’ work in the 1970s and ’80s led to the creation of powerful, lightweight and rechargeable batteries used in nearly every smartphone or laptop computer, and in billions of cameras and power tools. Astronauts on the International Space Station rely on them, and engineers working on renewable energy grids often turn to them. By storing electricity generated when sunlight and wind are at their peak, lithium-ion batteries can reduce dependence on fossil fuel energy sources and help lessen the effect of climate change.
Whittingham, 77, a professor at Binghamton University, State University of New York, and one of the three winners, said that he always hoped lithium-ion technology would grow, “but we never envisaged it growing this far. We never imagined it being ubiquitous in things like iphones.”
Goodenough, 97, is a professor at the University of Texas at Austin. With the award he becomes the oldest Nobel Prize winner, but is still active in research.
Yoshino, 71, is an honorary fellow for the Asahi Kasei Corp. in Tokyo and a professor at Meijo University in Nagoya, Japan. He said after the announcement that he was pleased that the technology could also help fight climate change, calling lithium-ion batteries “suitable for a sustainable society.”
For many years, there were no major advancements in battery technology. But the Arab oil embargo of 1973 made many scientists realize the extent of society’s dependence on fossil fuels. Whittingham, who was working for Exxon at the time, began searching for improved ways to store energy from renewable sources and power electric cars.
He knew that lithium would make a good anode because it released electrons easily. It also had the advantage of being the lightest metal. So Whittingham started looking for materials that had a high energy density and captured lithium-ions in the cathode—the side of your battery with the plus sign.
Whittingham discovered that titanium disulfide, which had never been used in batteries before, had a molecular structure that let lithium-ions into small pockets. This resulted in the first functional lithium battery.
“The big advantage of this technology was that lithiumion stored about 10 times as much energy as lead-acid or 5 times as much as nickelcadmium,” Whittingham said. Lithium-ion batteries were also extremely lightweight and required little maintenance. “So there was a huge incentive to move to lithium-ion.”
Unfortunately, Whittingham’s new battery had a problem. When it was repeatedly charged, thin strands of metallic lithium would grow out from the negative electrode. Sometimes, the strands would grow long enough that they reached the cathode and short-circuited the battery, and could cause an explosion.
Goodenough, then at Oxford, predicted that lithiumion batteries would have greater potential if the cathode were made with a different material. He noticed that cobalt oxide was similar in structure to titanium disulfide. It could tolerate lithium being pushed into it and pulled out over and over. It also made the lithium-ion battery almost twice as powerful as Whittingham’s. The battery now generated 4 volts.
Building from Goodenough’s work, Yoshino, who was at the Asahi Kasei Corp. in Japan, then showed that more complicated carbonbased electrodes could house lithium-ions in between their layers too. This eliminated pure lithium from the battery entirely. Instead, the system used only lithiumions, which are safer.
These developments ultimately led to commercialization of the lithium-ion battery in 1991 by another Japanese electronics giant, Sony Corp.
The compact nature and reliability of lithium-ion batteries made the technology a staple in electronics that had once been powered primarily by disposable batteries that consumers always seemed to run out of at the wrong time. That included radios, hand-held gaming devices, laptop computers and eventually smartphones and wearable computers.
But the technology has its flaws, too.
There is a limited number of times that a lithium-ion battery can be replenished before it deteriorates and can no longer hold a charge. In addition, a faultily designed lithium-ion battery can turn into a miniature bomb.
Some of the biggest tech product recalls have involved battery defects. In 2006, Dell recalled 4.1 million laptop batteries because they could erupt in flames. More recently, Samsung Electronics recalled and discontinued the Galaxy Note 7, its flagship smartphone, after several reports of the device exploding.
Technologists often point to lithium-ion as an innovation roadblock: While computer chips have doubled in speed every few years and digital displays have become significantly brighter and sharper, tech companies have made only incremental improvements on batteries; there’s not much that engineers can do beyond making the batteries bigger and implementing software algorithms to make hardware more power efficient.
Despite the hiccups, companies continue to rely on the batteries because they can be cheaply and reliably reproduced. They have also been scaled up for use in larger settings.
Energy storage, most often using lithium-ion battery technology, is widely seen as necessary for transforming the electric grid to a carbonfree system and combating the effects of climate change. Most electricity in the United States—and in many other parts of the world—comes from fossil fuel sources, predominantly natural gas but also coal.
Battery technology helps replace those carbon-emitting sources because it allows power companies to store excess solar and wind power when the sun does not shine nor the wind blow—the weakness of those carbon-free sources.
The most critical area for the electric grid has been providing power when people return home from work during the summer and turn on their air-conditioners, cook dinner and wash clothes, when utilities often rely on natural gas plants designed to meet those periods of high demand, known as peaking plants, which typically are more expensive.
“What’s exciting about lithium-ion technology is it has the power to unlock the sun 24-7 to really help renewable energy power our future in a way that we haven’t been able to capture until now,” said Bernadette Del Chiaro, executive director of the California Solar and Storage Association, an industry group.
Scientists have experimented with new power technologies that use alternate methods to replenish batteries, like pulling energy from the air or through radio signals. But any potential successor to lithium-ion would have to undergo rigorous safety tests before being introduced to the public.
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