Study of Local Structure and Li Dynamics in Li_4+xTi₅O₁₂ (0≤ x ≤5) Using ⁶Li and ⁷Li NMR Spectroscopy

Temperature-dependent Li vacancy diffusion in Li4Ti5O12 by means of first principles molecular dynamic simulations

“…Overall, the results obtained are in good agreement with experimental studies such as those of [31][32][33][53][54][55][56] which agree that Li ion transport occurs preferentially via the 8a and 16c Wyckoff positions. However, we could not find evidence for a diffusion involving the 32e Wyckoff positions (see path I*), as proposed by Laumann et al who analyzed NMR measurements.…”

“…On the basis of their NMR measurements, Wilkening et al concluded that the Li vacancy diffusion occurs mainly via path I. 31 The Li ion transport was also studied experimentally using NMR by Wagemaker et al 32 (T = 148-473 K) and Hain et al 33 (T = 298-673 K), who obtained similar results to Wilkening et al 31 In addition, NMR measurements and molecular dynamic simulations with an empirical interaction potential by Vijayakumar et al showed that above a temperature of 600 K reoccupation of Li ions from an 8a to a 16c position occurs, leading to a partial occupation of these two Wyckoff positions and a Li vacancy diffusion along path III in lithium-poor LTO (Li 4 Ti 5 O 12 ). 34 III 16c(oct.) init 2 8a(tet.)…”

Ultrathin Li4Ti5O12 Nanosheets as Anode Materials for Lithium and Sodium Storage

“…lithiation), three Li + ions can be inserted into the 16c sites, at the same time, the three Li + ions in the 8a sites will move to the 16c sites ([Li 6 ] 16c [Ti 5 Li] 16d O 12 ). 12,13 This reaction is highly reversible, with less than 1% volume change and a theoretical capacity of around 175 mAh g -1 . Besides, LTO can also be used as an anode material for Na ion batteries, with a working potential at about 0.8 V (vs. Na/Na + ).…”

“…[7][8][9][10][11] Lithium titanium oxide spinel (Li 4 Ti 5 O 12 , LTO) with a flat plateau at about 1.55 V (vs. Li/Li + ) is one of the most popular anode materials for Li ion batteries. It is safer and more stable than graphite so it has been considered to be an alternative of carbon-based anode materials, [12][13][14][15] especially for batteries in high power requirement.…”

In situ NMR observation of the lithium extraction/insertion from LiCoO2 cathode

“…Nuclear magnetic resonance (NMR) spectroscopy is a promising tool for this purpose. 6,7 Li NMR spectra have been acquired ex situ for the LIB positive and negative electrode materials to obtain structural information on Li + ions [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. A 7 Li magic-angle spinning (MAS) NMR study revealed that the Li x CoO 2 O3-II phase obtained by the electrochemical delithiation showed a Knight shift at 60-100 ppm [10].…”