Abstract
There is consensus on the fact that one of the main limitations of Li air batteries (LABs) is the insulating character of Li2O2 and that it becomes crucial to explore new conduction paths. Recent studies indicate that doping with chloride increases the ion conductivity of Li2O2, although to a much lesser extent than expected if chloride is assumed to be a donor dopant [Gerbig et al., Adv. Mater., 2013, 25, 3129]. Subsequently, it has been shown that the addition of lithium chloride, LiCl, to the battery electrolyte increases its discharge capacity, while this effect is not observed with other halogens [Matsuda et al., J. Phys. Chem. C, 2016, 120, 13360]. This fact was attributed to an increase in the conductivity of Cl-doped Li2O2, but still the responsible mechanism is not clear. In this work, we have performed first principle calculations to study the effect of the different halogens (F, Cl, Br, I) as substitutional defects on the electronic and transport properties of Li2O2. We have calculated the formation energies of the different defects and impurities and we analysed how they affect the activation barriers and diffusion coefficients. We have demonstrated that the chloride does not behave like a donor dopant, thus explain...Continue Reading
References
Feb 15, 1995·Physical Review. B, Condensed Matter·G Makov, M C Payne
Oct 15, 1996·Physical Review. B, Condensed Matter·G Kresse, J Furthmüller
Mar 18, 2005·Acta Crystallographica. Section B, Structural Science·Luis Guillermo Cota, Pablo de la Mora
Dec 21, 2006·The Journal of Chemical Physics·Aliaksandr V KrukauGustavo E Scuseria
Feb 1, 2008·Physical Review Letters·M ShishkinG Kresse
Feb 23, 2010·The Journal of Chemical Physics·J S HummelshøjJ K Nørskov
Dec 14, 2011·Journal of the American Chemical Society·Maxwell D RadinDonald J Siegel
May 8, 2013·Advanced Materials·Oliver GerbigJoachim Maier
Oct 24, 2014·Journal of the American Chemical Society·Swapna GanapathyMarnix Wagemaker
Nov 8, 2014·Chemical Reviews·Alan C Luntz, Bryan D McCloskey
Nov 21, 2014·Nature Chemistry·Lee JohnsonPeter G Bruce
Jan 28, 2015·ACS Applied Materials & Interfaces·Jonathan HøjbergAlan C Luntz
Jul 17, 2015·Chemical Communications : Chem Comm·Bryan D McCloskeySara E Renfrew