Li<sub>2</sub>MnO<sub>3</sub>: A Catalyst for a Liquid Cl<sub>2</sub> Electrode in Low‐Temperature Aqueous Batteries
Yiming Sui, Zengqing Zhuo, Ming Lei, Lu Wang, Mingliang Yu, Alexis M. Scida, Sean K. Sandstrom, William F. Stickle, Timothy D. O’Larey, De‐en Jiang, Wanli Yang, Xiulei Ji
Abstract
Abstract Li 2 MnO 3 has been contemplated as a high‐capacity cathode candidate for Li‐ion batteries; however, it evolves oxygen during battery charging under ambient conditions, which hinders a reversible reaction. However, it is unclear if this irreversible process still holds under subambient conditions. Here, the low‐temperature electrochemical properties of Li 2 MnO 3 in an aqueous LiCl electrolyte are evaluated and a reversible discharge capacity of 302 mAh g −1 at a potential of 1.0 V versus Ag/AgCl at −78 °C with good rate capability and stable cycling performance, in sharp contrast to the findings in a typical Li 2 MnO 3 cell cycled at room temperature, is observed. However, the results reveal that the capacity does not originate from the reversible oxygen oxidation in Li 2 MnO 3 but the reversible Cl 2 (l)/Cl − (aq.) redox from the electrolyte. The results demonstrate the good catalytic properties of Li 2 MnO 3 to promote the Cl 2 /Cl − redox at low temperatures.