Beyond lithium-ion batteries: A computational study on Na-S and Na-O batteries

2016 International Conference on Defects in Insulating Materials

Masedi, M.C.^1,2 ; Ngoepe, P.E.^1 ; Sithole, H.M.^2

Materials Modelling Centre, University of Limpopo, School of Physical and Minerals Sciences, Private Bag x1106, Sovenga

0727, South Africa^1

CSIR, Meraka Institute, Meiring Naude, Brummeria, P. O. Box 395, Pretoria

0001, South Africa^2

关键词: Computational studies;    Generalized gradient approximations;    Heats of formation;    Mechanical and electronic properties;    Mechanically stable;    Perdew-burke-ernzerhof;    Phonon dispersions;    Pseudopotential calculation;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/169/1/012001/pdf
DOI  :  10.1088/1757-899X/169/1/012001

来源: IOP

【 摘 要 】

The first principle pseudopotential calculations based on the Perdew-Burke-Ernzerhof (PBE) form of generalized gradient approximation (GGA) within density functional theory (DFT) has been utilized to investigate the stabilities of insoluble discharge products of oxygen and sulphur in the Na-O and Na-S batteries. Their structural, mechanical and electronic properties were determined. The lattice parameters were well reproduced and agree with the available experimental data. The heats of formation predict that all structures are generally stable and Na2S has the lowest value. The elastic constants suggest that all the structures are mechanically stable which in good agreement with the calculated phonon dispersions.