Metal-Air Batteries
Authors: Bruce Peter G. 
Published: February 2020

Li-ion and related battery technologies will be important for years to come. However, society needs energy storage that exceeds that of Li-ion batteries. We must explore alternatives to Li-ion if we are to have any hope of meeting the long-term needs for energy storage. One alternative is the Li-air (O2) battery, Fig. 1; its theoretical specific energy exceeds that of Li-ion, but many hurdles face its realization.[1-5]

One spin-off of the recent interest in rechargeable Li-O2 batteries, based on aprotic electrolytes is that it has highlighted the importance of understanding the fundamental oxygen redox processes at the positive electrode within the battery.[6-15] As a result of these fundamental studies it is generally accepted that a solution growth mechanism for Li2O2 will be required to achieve high rates and capacities, avoiding the formation of passivating Li2O2 films on the electrode surface.  Recent results exploring the electrochemical mechanism of O2 reduction to form Li2O2 at the positive electrode have identified new strategies to achieve this by exploiting the effect of the electrolyte solution. Moving to a solution phase discharge mechanism highlights the requirement for charge mediation between the electroactive species and the electrode, thus using solid Li2O2 simply as a storage material for lithium ions and electrons. The implications of this will be discussed

REFERENCES

[1]. Bruce, P. G.; Freunberger, S. A.; Hardwick, L. J.; Tarascon, J.-M. Nature Materials
2012, 11, 19. [2]. Lu, Y. C.; Gallant, B. M.; Kwabi, D. G.; Harding, J. R.; Mitchell, R. R.; Whittingham, M. S.; Shao-Horn, Y. Energy & Environmental Science
2013, 6, 750. [3]. Black, R.; Adams, B.; Nazar, L. F. Advanced Energy Materials
2012, 2, 801. [4]. Girishkumar, G.; McCloskey, B.; Luntz, A. C.; Swanson, S.; Wilcke, W. The Journal of Physical Chemistry Letters
2010, 1, 2193. [5]. Li, F.; Zhang, T.; Zhou, H. Energy & Environmental Science
2013, 6, 1125. [6]. Adams, B. D.; Radtke, C.; Black, R.; Trudeau, M. L.; Zaghib, K.; Nazar, L. F. Energy & Environmental Science
2013, 6, 1772. [7]. Horstmann, B.; Gallant, B.; Mitchell, R.; Bessler, W. G.; Shao-Horn, Y.; Bazant, M. Z. The Journal of Physical Chemistry Letters
2013, 4, 4217. [8]. Hummelshoj, J. S.; Luntz, A. C.; Norskov, J. K. The Journal of Chemical Physics
2013, 138, 034703. [9]. McCloskey, B. D.; Scheffler, R.; Speidel, A.; Girishkumar, G.; Luntz, A. C. The Journal of Physical Chemistry C
2012, 116, 23897. [10]. Mitchell, R. R.; Gallant, B. M.; Shao-Horn, Y.; Thompson, C. V. The Journal of Physical Chemistry Letters
2013, 4, 1060. [11]. Trahan, M. J.; Mukerjee, S.; Plichta, E. J.; Hendrickson, M. A.; Abraham, K. M. Journal of The Electrochemical Society
2013, 160, A259. [12]. Sharon, D.; Etacheri, V.; Garsuch, A.; Afri, M.; Frimer, A. A.; Aurbach, D. The Journal of Physical Chemistry Letters
2012, 4, 127. [13]. Jung, H. G.; Kim, H. S.; Park, J. B.; Oh, I. H.; Hassoun, J.; Yoon, C. S.; Scrosati, B.; Sun, Y. K. Nano Letters
2012, 12, 4333. [14]. Peng, Z.; Freunberger, S. A.; Hardwick, L. J.; Chen, Y.; Giordani, V.; Barde, F.; Novak, P.; Graham, D.; Tarascon, J. M.; Bruce, P. G. Angewandte Chemie International Edition
2011, 50, 6351. [15]. Zhai, D.; Wang, H. H.; Yang, J.; Lau, K. C.; Li, K.; Amine, K.; Curtiss, L. A. Journal of the American Chemical Society
2013, 135, 15364.