Insight into lithium transport in lithium nitridometallate battery materials from muon spin relaxation

Powell, Andrew S.; Stoeva, Zlatka; Lord, James S.; Smith, Ronald I.; Gregory, Duncan H.; Titman, Jeremy J.

Abstract

Muon spin relaxation and powder neutron diffraction have been combined to study three lithium cobalt nitride battery materials. Neutron diffraction shows that these retain the P6/mmm space group of Li3N with Co located only on Li(1) sites. The lattice parameters vary smoothly with the degree of metal substitution, such that the [Li2N] layers expand while the layer separation contracts, as observed previously for similar series of Cu- and Ni-substituted materials. However, in contrast to the latter, the Li3-x-yCoxN phases exhibit Curie-Weiss paramagnetism and this prevents the use of nuclear magnetic resonance to measure Li+ transport parameters. Therefore, muon spin relaxation has been employed here as an alternative technique to obtain quantitative information about Li+ diffusion. Muon spin relaxation shows that Li+ diffusion in Li3-x- yCoxN is anisotropic with transport confined to the [Li2N] plane at low temperature and exchange between Li(1) and Li(2) sites dominant at high temperature. By a comparison with previous studies some general trends have been established across a range of Cu-, Ni- and Co-substituted materials. For intra-layer diffusion Ea decreases as metal substitution increases and the corresponding expansion of the layers results in a more open pathway for Li+ diffusion. However, an optimal value of x is found with a ≈ 3.69 Å after which the concomitant contraction in layer spacing reduces the polarizability of the lattice framework.

Citation

Powell, A. S., Stoeva, Z., Lord, J. S., Smith, R. I., Gregory, D. H., & Titman, J. J. (2013). Insight into lithium transport in lithium nitridometallate battery materials from muon spin relaxation. Physical Chemistry Chemical Physics, 15(3), https://doi.org/10.1039/c2cp43318d

• Journal Article Type: Article
• Publication Date: Jan 1, 2013
• Deposit Date: Aug 15, 2014
• Publicly Available Date: Aug 15, 2014
• Journal: Physical Chemistry Chemical Physics
• Print ISSN: 1463-9076
• Electronic ISSN: 1463-9084
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 3
• DOI: https://doi.org/10.1039/c2cp43318d
• Public URL: https://nottingham-repository.worktribe.com/output/1005401
• Publisher URL: http://pubs.rsc.org/en/Content/ArticleLanding/2013/CP/c2cp43318d#!divAbstract