TOKYO -- Japanese researcher Akira Yoshino, one of the three 2019 Nobel Prize winners for chemistry, is known as the father of the lithium-ion battery, which powers smartphones, laptops and countless electronic devices today. Expected to command a $65 billion global market by 2022, the battery will now drive the growth of electric vehicles and other next-generation autos.
Yoshino, now an honorary fellow at Japanese chemical producer Asahi Kasei, was not a battery expert when he joined the company in 1972. He was among the 350 new hires that year, but was one of a handful of researchers with masters degrees.
His big break came in 1981 when he was assigned to a project that sought to discover new business applications for an electrically conductive plastic known as polyacetylene, which was developed by Japanese researcher Hideki Shirakawa, who himself won the Nobel Prize in 2000.
While analyzing the characteristics of the polyacetylene, Yoshino felt that the most promising application would be in batteries. "Perhaps the material can be used to make a rechargeable battery," he thought.
During 1980s, the term "portable" began to surface as a keyword of the future. Electronic companies were striving to create video cameras and other new electronic devices that would be easy to carry around. But further miniaturization depended on batteries that could produce high voltage.
A battery requires a positive and a negative electrode. Yoshino was researching ways to use polyacetylene as a negative electrode, but was struggling to find a positive electrode to accompany it.
Historic discoveries occur by chance. It was December 1982, and Yoshino's workplace was undergoing a year-end office cleaning. With nothing to do that afternoon, Yoshino picked up an overseas research paper that he had ordered a while ago but had not had a chance to read.
Flipping through the pages, Yoshino came across a surprise find. John B. Goodenough, an Oxford University professor, had written in a 1980 paper that a material called "lithium cobalt oxide" works as a powerful positive electrode for rechargeable batteries. The only problem was that there was no negative electrode to match it, Goodenough had said.
"What if I used polyacetylene?" Yoshino thought. The following month he carefully followed what Goodenough had written to create lithium cobalt oxide himself and combined it with the polymer. It worked. He could charge the battery and it discharged electricity smoothly. It was the breakthrough he had waited for. The basic foundation of the lithium-ion battery was established.
He later substituted polyacetylene with carbon fiber, which was Asahi Kasei's specialty. Today, his inventions power billions of smartphones throughout the world, as well as electric vehicles and countless other devices. Yoshino, Goodenough and American scientist M. Stanley Whittingham won the Nobel Prize on Oct. 9.
The global market for lithium-ion batteries will amount to roughly 4.79 trillion yen ($45 billion) this year, estimates Tokyo-based data provider Fuji Keizai. The scale is expected to grow 50% to about $65 billion in 2022.
Lithium-ion batteries have become a field that Japanese material producers have found strength. In recent years, global competition has mounted with the rise of Chinese and South Korean rivals.
When Yoshino arrived at the news conference venue in Tokyo on the evening of Oct. 9, the Asahi Kasei staff that had gathered gave him a standing ovation.
"I was more befuddled than I was happy," Yoshino said of his initial feelings. He said he was informed by the Nobel Committee just moments before the announcement.
"They told me to keep it a secret until it was announced so I said, 'Yes, I will,'" he laughed.
"As we move to a world of renewable energies, lithium-ion batteries will be one factor that will contribute to the environment," he told reporters. "I think that is the reason I was given the award."