Hot lithium-oxygen batteries charge ahead

• Published in: Science (American Association for the Advancement of Science) Vol. 361; no. 6404; p. 758
• Main Authors: Feng, Shuting, Lunger, Jaclyn R, Johnson, Jeremiah A, Shao-Horn, Yang
• Format: Journal Article
• Language: English
• Published: United States The American Association for the Advancement of Science 24.08.2018
• Subjects: Batteries; Electric Power Supplies; Electrodes; Electrons; Energy storage; Lithium; Lithium batteries; Lithium oxides; Lithium-ion batteries; Metal air batteries; Molten salt electrolytes; Molten salts; Nickel; Nonaqueous electrolytes; Organic chemistry; Oxygen; Peroxide; Reactive oxygen species; Rechargeable batteries; Solar energy; Stainless steel; Storage batteries
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aau4792

Molten salt electrolytes and nickel oxide–based electrodes enable four-electron transfer The need to increase the energy storage per unit mass or volume and to decrease stored-energy cost from solar and wind ( 1 ) has motivated research efforts toward developing alternative battery chemistries. In particular, lithium-oxygen (Li-O 2 ) batteries offer great promise ( 2 , 3 ). During discharge, oxygen can be reduced to form either peroxide (Li 2 O 2 in a two-electron pathway) or oxide (Li 2 O in a four-electron pathway). The estimated energy densities of lithium-oxygen batteries based on peroxide and oxide are two and four times higher than that of lithium-ion batteries, respectively ( 3 ), but degradation of organic electrolytes and of oxygen electrodes (typically made of carbon) by these reactive oxygen species has limited the reversibility of these systems. On page 777 of this issue, Xia et al. ( 4 ) address these issues by using inorganic components—a molten salt electrolyte and a nickel-based oxide supported by stainless steel mesh for the oxygen electrode—and demonstrate reversible operation for the four-electron–pathway Li-O 2 battery at 150°C.