Three important developments regarding lithium batteries occurred in the 1980s. In 1980, an American chemist, John B. Goodenough, discovered the LiCoO 2 (Lithium cobalt oxide) cathode (positive lead) and a Moroccan research scientist, Rachid Yazami, discovered the graphite anode (negative lead) with the solid electrolyte. In 1981, Japanese chemists Tokio Yamabe and Shizukuni Yata discovered a novel nano-carbonacious-PAS (polyacene) and found that it was very effective for the anode in the conventional liquid electrolyte. This led a research team managed by Akira Yoshino of Asahi Chemical, Japan, to build the first lithium-ion battery prototype in 1985, a rechargeable and more stable version of the lithium battery; Sony commercialized the lithium-ion battery in 1991. In 2019, John Goodenough, Stanley Whittingham, and Akira Yoshino, were awarded the Nobel Prize in Chemistry, for their development of lithium-ion batteries.