Journalartikel
Autorenliste: Bianchini, M; Schiele, A; Schweidler, S; Sicolo, S; Fauth, F; Suard, E; Indris, S; Mazilkin, A; Nagel, P; Schuppler, S; Merz, M; Hartmann, P; Brezesinski, T; Janek, J
Jahr der Veröffentlichung: 2020
Seiten: 9211-9227
Zeitschrift: Chemistry of Materials
Bandnummer: 32
Heftnummer: 21
ISSN: 0897-4756
DOI Link: https://doi.org/10.1021/acs.chemmater.0c02880
Verlag: American Chemical Society
Abstract:
The Li-Ni-O phase diagram contains a variety of compounds, most of which are electrochemically active in Li-ion batteries. Other than the well-known LiNiO2, here we report a facile solid-state method to prepare Li2NiO3 and other Li-rich Ni oxides of composition Li1+xNi1-xO2, (0 <= x <= 0.33). We characterize their crystal and electronic structure, exhibiting a highly oxidized Ni state and defects of various nature (Li-Ni disorder, stacking faults, oxygen vacancies). We then investigate the use of Li2NiO3 as a cathode active material and show its remarkably high specific capacity, which however fades quickly. While we demonstrate that the initial capacity is due to irreversible O-2 release, such process stops quickly in favor of more classical reversible redox mechanisms that allow cycling the material for >100 cycles. After the severe oxygen loss (similar to 15-20%) and prolonged cycling, the Bragg reflections of Li2NiO3 disappear. Analysis of the diffracted intensities suggests the resulting phase is a disordered rock salt-type material with high Li content, close to Li0.5Ni0.5O, never reported to date and capable of Li diffusion. Our findings demonstrate that the Li-Ni-O phase diagram has not been fully investigated yet, especially concerning the preparation of new promising materials by out-of-equilibrium methods.
Zitierstile
Harvard-Zitierstil: Bianchini, M., Schiele, A., Schweidler, S., Sicolo, S., Fauth, F., Suard, E., et al. (2020) From LiNiO2 to Li2NiO3: Synthesis, Structures and Electrochemical Mechanisms in Li-Rich Nickel Oxides, Chemistry of Materials, 32(21), pp. 9211-9227. https://doi.org/10.1021/acs.chemmater.0c02880
APA-Zitierstil: Bianchini, M., Schiele, A., Schweidler, S., Sicolo, S., Fauth, F., Suard, E., Indris, S., Mazilkin, A., Nagel, P., Schuppler, S., Merz, M., Hartmann, P., Brezesinski, T., & Janek, J. (2020). From LiNiO2 to Li2NiO3: Synthesis, Structures and Electrochemical Mechanisms in Li-Rich Nickel Oxides. Chemistry of Materials. 32(21), 9211-9227. https://doi.org/10.1021/acs.chemmater.0c02880
