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Abstract Li2MnO3has 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 Li2MnO3in an aqueous LiCl electrolyte are evaluated and a reversible discharge capacity of 302 mAh g−1at 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 Li2MnO3cell cycled at room temperature, is observed. However, the results reveal that the capacity does not originate from the reversible oxygen oxidation in Li2MnO3but the reversible Cl2(l)/Cl−(aq.) redox from the electrolyte. The results demonstrate the good catalytic properties of Li2MnO3to promote the Cl2/Cl−redox at low temperatures.
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This content will become publicly available on July 14, 2026
Computational screening of perovskite catalysts for low-temperature Cl2/Cl− redox batteries
There is a growing interest in anionic redox chemistry to improve the energy densities of rechargeable batteries, and the reversible chlorine/chloride reactions are a promising option for low-temperature applications. As such, understanding Cl adsorption on the cathode surfaces is important in revealing the intimate connection between catalysis and charge storage via the reversible surface Cl2/Cl− redox chemistry. In this work, we investigate the adsorption of Cl on various SrBO3 perovskites, with B being 3d transition metals, by using density functional theory calculations and interpretable machine learning. We identify the electronic structure descriptors crucial for Cl adsorption. Our findings reveal that SrCoO3 exhibits optimal Cl adsorption at the top of the volcano curve for Cl2 evolution, suggesting its potential as a catalyst to enable a low-temperature, liquid Cl2 electrode.
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- PAR ID:
- 10632135
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 163
- Issue:
- 2
- ISSN:
- 0021-9606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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