Structural and electrochemical properties of LiNi1/3Co1/3Mn1/3O2 material prepared by a two-step synthesis via oxalate precursor

Abstract

LiNi 1/3 Co 1/3 Mn 1/3 O 2 (LNMCO) powders were formed by a two-step synthesis including preparation of an oxalate precursor by "chimie douce" followed by a solidstate reaction with lithium hydroxide. The product was characterized by TG-DTA, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Raman spectroscopy, electron spin resonance (ESR), and SQUID magnetometry. XRD data revealed well-crystallized layered LNMCO with α-NaFeO 2 -type structure (R-3 m space group). Morphology studied by SEM and TEM shows submicronic particles of 400-800 nm with a tendency to agglomerate. The local structure investigated by vibrational spectroscopy (FTIR, Raman), ESR, and SQUID measurements confirms the well-crystallized lattice with a cation disorder of 2.6% Ni 2+ ions in Li(3b) sites. Electrochemical tests were carried out in the potential range 2.5-4.5 V vs. lithium metal on samples heated at 900°C for 12 h. Initial discharge capacity is 154 mAh/g at C/5, while a capacity of 82 mAh/g is still delivered at 10

Doped Nanoscale NMC333 as Cathode Materials for Li-Ion Batteries

“…Values of the lattice parameter a (which related to the average metal-metal intraslab distance) and c (which related to the average interslab distance) calculated for parent and doped NMC333 are summarized in Table 1. The lattice parameters of parent LiNi 1/3 Mn 1/3 Co 1/3 O 2 were consistent with previous reported results [36,47]. The material being an ionic compound, the dopant ions were inserted preferentially on sites that minimize the cost in Coulomb energy.…”

Nanocellulose‐Mediated Transition of Lithium‐Rich Pseudo‐Quaternary Metal Oxide Nanoparticles into Lithium Nickel Cobalt Manganese Oxide (NCM) Nanostructures

“…Hereby, in a first approximation we assume that the Raman signal for the NCMs may derive from the superposition of the pure phases LiNiO 2 , LiCoO 2 and LiMnO 2 . Therefore, we are dealing with two peaks for the rhombohedral LiNiO 2 and LiCoO 2 (A 1g and E g ) and three signals, two A g modes and one B g mode, for the monoclinic layered LiMnO 2 . While the E g band is not clearly visible as it overlaps with the A 1g peak, the latter can be determined for all NCMs.…”

“…Therefore, we are dealing with two peaks for the rhombohedral LiNiO 2 and LiCoO 2 (A 1g and E g ) and three signals, two A g modes and one B g mode, for the monoclinic layered LiMnO 2 . [73][74][75][76] While the E g band is not clearly visible as it overlaps with the A 1g peak, the latter can be determined for all NCMs. For NCM333 this peak is at 588 cm À 1 and slightly decreases to 553 cm À 1 with rising Ni content since the A 1g peak appears at 544 cm À 1 for pure LiNiO 2 .…”

Effects of chelators on the structure and electrochemical properties of Li-rich Li1.2Ni0.13Co0.13Mn0.54O2 cathode materials

“…To satisfy this purpose, intense research is currently done on advanced positive electrode materials, since they are limiting components of LIBs [1,2]. In particular, layered lithium-rich oxides, represented by xLi The remarkably high capacity of LLNMC is obtained when the Li 2 MnO 3 component is activated, which requires a charge potential higher than 4.5 V [8][9][10]. However, this large potential leads to endangerment for its crystal structure, so that this electrode suffers from a high initial irreversible capacity loss (ICL), a low rate capability and increasing polarization upon cycle number [11].…”