2019 Nobel Prize in Chemistry goes to inventors of lithium-ion batteries.
"I am overcome with gratitude at receiving this award, and I honestly have so many people to thank I don't know where to begin," said Stan Whittingham, Distinguished Professor, Binghamton University, State University of New York. "The research I have been involved with for over 30 years has helped advance how we store and use energy at a foundational level, and it is my hope that this recognition will help to shine a much-needed light on the nation's energy future." He currently serves on the Editorial Boards for both MRS Bulletin and MRS Energy & Sustainability published jointly by the Materials Research Society (MRS) and Cambridge University Press.
Goodenough (The University of Texas at Austin) and Yoshino (Asahi Kasei Corporation, Tokyo, Japan, and Meijo University, Nagoya, Japan) built on the seminal research of Whittingham in the 1970s to produce the first commercially viable lithium-ion battery in 1985. With further development, lithium-ion batteries reached the market in 1991. In the years since, long-lasting, lightweight, rechargeable lithium-ion batteries have powered the revolution in mobile personal electronics, long-range electric vehicles, and storage of energy generated by intermittent renewable resources, such as solar and wind energy, among other applications. Lithium-ion batteries largely displaced the Ni-Cd and nickel metal hydride batteries that had dominated the sector until that time.
“These three scientists and engineers are true, inspiring pioneers in our field,” says Shirley Meng, a professor in the Department of NanoEngineering at the University of California San Diego and founding director of the Sustainable Power and Energy Center. “Their breakthroughs in intercalated materials chemistry led to a paradigm shift in energy storage technology. Today, we are experiencing a true revolution where humankind can enjoy abundant energy with low cost and a [small] carbon footprint.” Meng is Editor-in-Chief of MRS Energy & Sustainability.
Whittingham was not planning to disrupt the battery sector when he began working on superconductors in the 1970s. Instead, in the midst of an energy crisis, he was looking for an alternative. Whittingham and coworkers, then at the Exxon Research and Engineering Company, built on the work of Walter Rüdorff to show that lithium can intercalate into the octahedral sites of the interlamellar spaces of LixTiS2 (an MX2-type material) over the whole stoichiometric range. Lithium’s very low standard reduction potential (Li+/Li couple 3.05 V versus SHE) made it a good candidate for high-density, high-voltage battery cells. Whittingham built the first lithium-ion battery with a titanium disulfide cathode and an anode made partially of metallic lithium. It generated more than 2 V, but the metallic lithium made explosion a possibility. “The taming of lithium was therefore of utmost importance for the battery development,” the Nobel Prize Committee wrote in a scientific report accompanying the Prize announcement.
Still, creating a battery that depended on lithium ions traveling between the anode and cathode and back again, and not on chemical reactions that break down electrodes, was a good first step toward creating a long-lasting battery.
In 1980, Goodenough and co-workers at Oxford University, UK, discovered that a cobalt oxide analogue of LixTiS2, namely LixCoO2, qualified as a good cathode material. The theoretical reasoning behind this was that if X is a small electronegative element in MX2, then cation uptake should result in a large negative free-energy change and a high cell voltage. CoO2 (X = oxygen) showed a high potential of ~45 V relative to Li+/Li, along with a high diffusion constant for lithium ions. Goodenough’s 1980 demonstration of a battery with a LixCoO2 cathode produced a high output of 4 V, but a reliable anode was still needed.
Then, in 1985, Yoshino and colleagues at the Asahi Kasei Corporation, Japan, showed that certain qualities of petroleum coke were stable under the required electrochemical conditions. Heat-treated petroleum coke was known to contain a mixture of crystalline (graphitic) and non-crystalline domains, into which large amounts of lithium ions could be intercalated. Using Li-intercalated petroleum coke as the anode and Goodenough’s LixCoO2 as the cathode, Yoshino produced a lithium-ion battery based on an ion transfer cell. Adding separator layers of polyethylene or polypropylene and using LiClO4 in propylene carbonate as the electrolyte, he created the first commercially viable lithium-ion batteryone that could be damaged without catching fire or exploding.
"Stan Whittingham originally outlined the mechanism of intercalation, followed by Goodenough inventing the ‘almost perfect’ cathode,” says Venkat Viswanathan, an associate professor of mechanical engineering at Carnegie Mellon University, providing a concise summation of the research. “Yoshino completed the story by fabricating a functioning rechargeable battery using a carbon-based anode and the Goodenough cathode!"
MRS Fellow Peter Green, deputy laboratory director for science and technology and the chief research officer for NREL in Golden, Colorado, calls this string of developments “one of the most important technological advances of our lifetime,” adding that, “it’s absolutely revolutionary.”
“The contribution of the Chemistry Nobel Prize winners today is immense,” says Rigoberto Advincula, professor of Macromolecular Science & Engineering at Case Western Reserve University. “As Editor-in-Chief of MRS Communications, I take note and pride of Prof. Goodenough and Prof. Whittingham as authors of the journal whose lasting work will be a reminder of materials science in everyday things!”
The Nobel Prizes will be awarded during a ceremony in Stockholm, Sweden, on December 10. The three winners will share 9 million Swedish krona (approximately USD$900,000), but more importantly, they will enter the rarefied realm of Nobel Laureate.
By Tim Palucka. Materials Research Society (MRS). Oct 16, 2019.