Nuclear Magnetic Resonance and X-Ray Absorption Spectroscopic Studies of Lithium Insertion in Silver Vanadium Oxide Cathodes

Published

February 19, 2017

Author(s)

N D. Leifer, A Colon, K Martocci, S G. Greenbaum, Faisal Alamgir, T B. Reddy, N R. Gleason, R A. Leising, E S. Takeuchi

Abstract

Structural studies have been carried out on Ag2V4O11 (silver vanadium oxide, SVO) and LixAg2V4O11, lithiated SVO with x = 0.72, 2.13 and 5.59 using Nuclear Magnetic Resonance (NMR) and X-ray Absorption Spectroscopy (XAS). Lithium-7 NMR indicates the formation of a Solid Electrolyte Interface (SEI) layer on the x = 0.72 sample and lithium intercalation into both octahedral and tetrahedral sites in the SVO lattice, and that most but not all of the Ag (I) is reduced prior to initiation of V(V) reduction. Vanadium-51 NMR studies of SVO and lithiated SVO show decreased crystallinity with increased lithiation, as previously reported. Silver XAS studies indicate the formation of metallic silver crystallites in the all lithiated samples. A comparison of XANES spectra for vanadium in these samples with those of reference compounds shows that some reduction of Vanadium (V) occurs in the lithiated SVO with x = 0.72 and increases with further lithiation leading to the formation of V(IV) and V(III) species. The results of this study indicate that vanadium(V) reduction occurs in parallel with silver (I) reduction during the initial stages of SVO lithiation, leading ultimately to the formation of vanadium (IV) and (III) species with further lithiation.

Citation

Journal of the Electrochemical Society

Pub Type

Journals

Citation

Leifer, N. , Colon, A. , Martocci, K. , Greenbaum, S. , Alamgir, F. , Reddy, T. , Gleason, N. , Leising, R. and Takeuchi, E. (2017), Nuclear Magnetic Resonance and X-Ray Absorption Spectroscopic Studies of Lithium Insertion in Silver Vanadium Oxide Cathodes, Journal of the Electrochemical Society (Accessed September 7, 2024)