Get access

Limitation of Discharge Capacity and Mechanisms of Air-Electrode Deactivation in Silicon–Air Batteries

Authors

  • Dr. Peter Jakes ,

    1. Forschungszentrum Jülich, Institut für Energie- und Klimaforschung, IEK-9, 52452 Jülich (Germany)
    2. Karlsruher Institut für Technologie (KIT), Anorganische Chemie, Materialforschung für neuartige Energiespeichersysteme, Engesserstr. 15, 76131 Karlsruhe (Germany)
    Search for more papers by this author
  • Gil Cohn,

    1. Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel)
    Search for more papers by this author
  • Prof. Dr. Yair Ein-Eli,

    1. Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel)
    Search for more papers by this author
  • Dr. Frieder Scheiba,

    1. Karlsruher Institut für Technologie (KIT), Institut für Angewandte Materialien (IAM-ESS), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany), Fax: (+49) 721-60848142
    Search for more papers by this author
  • Prof. Dr. Helmut Ehrenberg,

    1. Karlsruher Institut für Technologie (KIT), Institut für Angewandte Materialien (IAM-ESS), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany), Fax: (+49) 721-60848142
    Search for more papers by this author
  • Dr. Rüdiger-A. Eichel 

    Corresponding author
    1. Karlsruher Institut für Technologie (KIT), Institut für Angewandte Materialien (IAM-ESS), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany), Fax: (+49) 721-60848142
    2. Forschungszentrum Jülich, Institut für Energie- und Klimaforschung, IEK-9, 52452 Jülich (Germany)
    • Karlsruher Institut für Technologie (KIT), Institut für Angewandte Materialien (IAM-ESS), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany), Fax: (+49) 721-60848142
    Search for more papers by this author

Abstract

The electrocatalytical process at the air cathode in novel silicon–air batteries using the room-temperature ionic liquid hydrophilic 1-ethyl-3-methylimidazolium oligofluorohydrogenate [EMI2.3 HFF] as electrolyte and highly doped silicon wafers as anodes is investigated by electrochemical means, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. The results obtained by XPS and EPR provide a model to describe the limited discharge capacity by means of a mechanism of air-electrode deactivation. In that respect, upon discharge the silicon-air battery′s cathode is not only blocked by silicon oxide reduction products, but also experiences a major modification in the MnO2 catalyst nature. The proposed modification of the MnO2 catalyst by means of a MnF2 surface layer greatly impacts the Si–air performance and describes a mechanism relevant for other metal–air batteries, such as the lithium–air. Moreover, the ability for this deactivation layer to form is greatly impacted by water in the electrolyte.

Get access to the full text of this article

Ancillary