Theoretical Studies of Zincate Contamination of $\gamma$ -MnO$_2$ in Deep-Cycled Rechargeable Zn/MnO$_2$ Batteries

ORAL

Abstract

Rechargeable alkaline Zn/MnO$_2$ batteries are attractive for large-scale energy storage because of their high energy density, non-toxicity, and low cost. However, efforts to develop rechargeable Zn/MnO$_2$ batteries have been hindered by a short cycle life due to the accumulation of irreversible redox reaction products in the $\gamma$-MnO$_2$ cathode. The penetration of Zn ions into the $\gamma$-MnO$_2$ electrode leads to the formation of hetaerolite (ZnMn$_2$O$_4$). The contamination of the $\gamma$-MnO$_2$ cathode material with hetaerolite reduces the battery capacity and eventually leads to the failure of the battery. We apply {\it ab initio} computational methods based on density functional theory to calculate the structure and formation energy of ZnMn$_2$O$_4$ using several different gradient corrected exchange-correlation functionals, including PBE, PBESol, and PBE+U. Our calculations show that the PBE and PBEsol functionals tend to underestimate the formation energy of hetaerolite, whereas the PBE+U functional significantly improves agreement with experiment. Using the results of our calculations, we analyze the influence of hetaerolite on the performance and cycle life of rechargeable Zn/MnO$_2$ batteries.

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Authors

  • Nirajan Paudel

    Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA

  • John Spence

    Brigham Young University, Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, Department of Scientific Research, The Metropolitan Museum of Art, New York, NY 10028, Century Darkroom, Toronto, ON M4M 2S1, Canada, Colorado State University, University of Waterloo, Southern Connecticut State University, Clemson University, Oak Ridge National Laboratory, University of Bordeaux, BYU REU Program, New Mexico State University, Arizona State University, Biodesign Institute, Center for Applied Structural Discovery, University of Utah, University of Hawaii, Johns Hopkins University, Embry-Riddle Aeronautical University, Arizona State University, Utah State University, Department of Physics, United States Air Force Academy, Department of Chemistry, Case Western Reserve University, Air Force Research Laboratory, Wright-Patterson Air Force Base, United States Air Force Academy, Lousiana State University, Brigham Young University - Provo, The University of New Mexico, Department of Physics and Astronomy, Brigham Young University, SLAC National Accelerator Laboratory, Department of Chemistry, Brigham Young University, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Center for Memory and Recording research, UCSD, Advanced Photon Source, Argonne National Laboratory, University of New Mexico, Los Alamos National Laboratory, University of Chicago

  • John Spence

    Brigham Young University, Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, Department of Scientific Research, The Metropolitan Museum of Art, New York, NY 10028, Century Darkroom, Toronto, ON M4M 2S1, Canada, Colorado State University, University of Waterloo, Southern Connecticut State University, Clemson University, Oak Ridge National Laboratory, University of Bordeaux, BYU REU Program, New Mexico State University, Arizona State University, Biodesign Institute, Center for Applied Structural Discovery, University of Utah, University of Hawaii, Johns Hopkins University, Embry-Riddle Aeronautical University, Arizona State University, Utah State University, Department of Physics, United States Air Force Academy, Department of Chemistry, Case Western Reserve University, Air Force Research Laboratory, Wright-Patterson Air Force Base, United States Air Force Academy, Lousiana State University, Brigham Young University - Provo, The University of New Mexico, Department of Physics and Astronomy, Brigham Young University, SLAC National Accelerator Laboratory, Department of Chemistry, Brigham Young University, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Center for Memory and Recording research, UCSD, Advanced Photon Source, Argonne National Laboratory, University of New Mexico, Los Alamos National Laboratory, University of Chicago

  • Igor Vasiliev

    Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Physics, New Mexico State University, Las Cruces, NM 88003 USA