Synthesis and Electrochemical Properties of LiNi0.5Mn1.5O4 Cathode Materials with Cr3+ and F− Composite Doping for Lithium-Ion Batteries

Abstract

A Cr3+ and F− composite-doped LiNi0.5Mn1.5O4 cathode material was synthesized by the solid-state method, and the influence of the doping amount on the material’s physical and electrochemical properties was investigated. The structure and morphology of the cathode material were characterized by XRD, SEM, TEM, and HRTEM, and the results revealed that the sample exhibited clear spinel features. No Cr3+ and F− impurity phases were found, and the spinel structure became more stable. The results of the charge/discharge tests, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) test results suggested that LiCr0.05Ni0.475Mn1.475O3.95F0.05 in which the Cr3+ and F− doping amounts were both 0.05, had the optimal electrochemical properties, with discharge rates of 0.1, 0.5, 2, 5, and 10 C and specific capacities of 134.18, 128.70, 123.62, 119.63, and 97.68 mAh g−1 , respectively. After 50 cycles at a rate of 2 C, LiCr0.05Ni0.475Mn1.475O3.95F0.05 showed extremely good cycling performance, with a discharge specific capacity of 121.02 mAh g−1 and a capacity retention rate of 97.9%. EIS test revealed that the doping clearly decreased the charge-transfer resistance.

Lithia-Based Nanocomposites Activated by Li2RuO3 for New Cathode Materials Rooted in the Oxygen Redox Reaction

“…These examples of ESSs are mostly based on secondary battery systems, which has led to rapid growth of the market share of Li-ion batteries (LIBs), considered the most advanced secondary battery. However, the energy density of current LIBs is not sufficient to meet the requirements of many applications [1–7]. Hence, much research has focused on improvement of the energy density of battery systems.…”

“…Hence, much research has focused on improvement of the energy density of battery systems. In particular, development of a superior cathode material exhibiting higher reversible capacity than conventional transition metal-based oxides is of great research interest [1–7].…”

Significant Improvement of LiMn₂O₄ Cathode Capacity by Introducing Trace Ni During Rapid Microwave-induced Solution Combustion

“…The X-ray photo-electron spectroscopy (XPS, PHI5000 Versaprobe-II, Ulvac The diffraction peak at about 2H = 30.7°is not found, suggesting that Ni element substitutes for Mn at 16d site of octahedron, not Li + at 8a of tetrahedron. 27,28 From the insert in Fig. 2b, it can be seen that the (4 0 0) diffraction peak shifts to high 2H angle, which results from the crystal cell contraction of LiMn Electrochemistry, (in press) samples, and the results are shown in the Fig.…”

Synthesis and Characterization of a Multication Doped Mn Spinel, LiNi0.3Cu0.1Fe0.2Mn1.4O4, as 5 V Positive Electrode Material

“…Doping modifications such as cation doping (Na, 9 Al, 10 Cr, 11 Fe, 12 Cu, 13 Sm, 14 Zr, 15 Nb, 16 Mo, 17 etc. ), anion doping (S, 18 P 19 ), or composite doping 20 of LNMO are amply reported. Among various cation substitutions, Fe influences the electrochemistry of spinels favorably.…”