On the Synthesis of Ramsdellite LiTiMO₄ (M = Ti, V, Cr, Mn, Fe): An Experimental and Computational Study of the Spinel–Ramsdellite Transformation

Abstract

The LiTiMO 4 (spinel) ↔ LiTiMO 4 (ramsdellite) transformation has been investigated by combining computational and experimental techniques, for M = Ti, V, Cr, Mn, and Fe, in order to understand the characteristics of this transformation and the influence of the metal M on the relative stability of the ramsdellite polymorph. The calculations predict that all the aforementioned LiTiMO 4 spinels are thermodynamically stable with respect to the ramsdellite polymorph, with the calculated enthalpy variation of the transformation being less than 40 kJ mol -1 . In the case of normal spinels [Li]

Lithium Insertion and Transport in the TiO2−B Anode Material: A Computational Study

“…Our results are in good agreement with preliminary neutron diffraction studies that indicate that Li occupies an off-center C site in bulk Li x TiO 2 −B for x ≤ 0.25 . Interestingly, an off-center position for inserted Li ions has also been calculated in the case of rutile TiO 2 …”

“…The present study uses advanced computational techniques based on density functional theory (DFT) to investigate, at the atomic level, the key issues of lithium insertion sites and diffusion pathways in the TiO 2 −B system. Such DFT techniques have been applied successfully to analogous studies of other TiO 2 polymorphs − and oxide materials for lithium batteries. − This study also extends our recent computational studies of lithium ion transport and surface structures of LiFePO 4 cathode materials. , The present simulations of the TiO 2 −B bulk are an informative and necessary preliminary to more complex simulations of surface and nanotube structures.…”

A review on first principles based studies for improvement of cathode material of lithium ion batteries

“…In the same way, LiTiMO 4 spinal to ramsdelite transformed LiTiMO 4 has also been studied with M = Ti, V and Cr. It was found that Li intercalation happened via the oxidation of M with potential 1.9 V (Ti), 3.1 V (V) and 4.2 V (Cr) [105,106] . A detailed theoretical and experimental analysis of bi doped LiMnMO 4 (M = Ti, V, Cr, Co, Fe, Ni and Cu) for the investigation of voltage profile for LiNiCuMn 2 O 4, shows a high voltage platue of 4.95 V. By studying the oxidation states for present metals Ni( + 2), Cu( + 2) and Mn( + 4), it was found that high voltage may be due to the extra electrons from oxygen atoms as Cu can't be further oxidized to + 4 oxidation state.…”

Electrochemical Oscillation during Galvanostatic Charging of LiCrTiO4 in Li-Ion Batteries

“…Materials 2021, 14, 3624 2 of 11 Recently, LiCrTiO 4 has been comprehensively studied due to its similar characteristics to Li 4 Ti 5 O 12 [22][23][24][25]. In this work, spinel LiCrTiO 4 was synthesized by using a high-temperature solid-state method, characterized with SEM, XRD, Raman and XPS measurements, and electrochemically tested in Li-ion batteries.…”