Mn–Fe-based oxide electrocatalysts for air electrodes of lithium–air batteries

• Published in: Journal of power sources 2013-12, Vol.244, p.17-22
• Main Authors: Minowa, Hironobu, Hayashi, Masahiko, Hayashi, Katsuya, Kobayashi, Ryuichi, Takahashi, Kazue
• Format: Article
• Language: English
• Subjects: Air electrode; Applied sciences; Catalysis; Catalysts: preparations and properties; Chemistry; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrocatalyst; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrochemistry; Exact sciences and technology; General and physical chemistry; Lithium–air battery; Miscellaneous (electroosmosis, electrophoresis, electrochromism, electrocrystallization, ...); Mn oxide; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.05.075

The electrochemical properties of lithium–air batteries incorporating air electrodes loaded with MnOx, which had different Mn valences as the electrocatalysts were examined in an organic electrolyte solution consisting of 1 mol l−1 lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/propylene carbonate (PC). Furthermore, we attempted to improve the battery performance by substituting the Mn site in MnOx with Fe, Ni, or Co. The batteries using Mn2−xFexO3 showed rather large 1st discharge capacities of 230 mAh g−1 at a current density of 0.25 mA cm−2 in a dry air atmosphere. The discharge and charge overpotentials were both greatly reduced by loading Mn2−xFexO3 catalysts. However, almost all of these oxides exhibited poor cycle performance. Of the oxides that we examined, Mn1.8Fe0.2O3 had comparatively stable cycle characteristics with a capacity loss of only 25% after 10 cycles. •The electrochemical properties of lithium–air batteries with MnOx were examined.•We attempted to improve battery performance by substituting the Mn with Fe, Ni, or Co.•The batteries using Mn2−xFexO3 showed large 1st discharge capacity of 230 mAh g−1.•Mn1.8Fe0.2O3 had stable cycle characteristics with a capacity loss of 25% after 10 cycles.