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arXiv · 2104.08316

LiNiO$_2$ as a high-entropy charge- and bond-disproportionated glass

Kateryna Foyevtsova·Ilya Elfimov·Joerg Rottler·George A. Sawatzky
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Abstract

Understanding microscopic properties of LiNiO$_2$, a Li-ion battery cathode material with extraordinarily high reversible capacity, has remained a challenge for decades. Based on extensive electronic structure calculations, which reveal a large number of nearly degenerate phases involving local Jahn-Teller effect as well as bond and oxygen-based charge disproportionation, we propose that LiNiO$_2$ exists in a high-entropy charge-glass like state at and below ambient temperatures. Recognizing the glassy nature of LiNiO$_2$ does not only explain its key experimental features, but also opens a new path in designing entropy-stabilized battery cathodes with superb capacities.

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Kateryna Foyevtsova, Ilya Elfimov, Joerg Rottler, George A. Sawatzky. 2021-04-16. LiNiO$_2$ as a high-entropy charge- and bond-disproportionated glass. https://doi.org/10.1103/physrevb.100.165104

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