The Li Ni0.2Mn0.2Co0.6O2 electrode materials: A structural and magnetic study
Graphical abstract: EPR signal of the Li{sub 0.6}Co{sub 0.6}Ni{sub 0.2}Mn{sub 0.2}O{sub 2} composition showing that Mn{sup 4+} ions are the solely paramagnetic ions in the structure. Highlights: Black-Right-Pointing-Pointer LiCo{sub 0.6}Ni{sub 0.2}Mn{sub 0.2}O{sub 2} was prepared by the combustion method with sucrose as a fuel. Black-Right-Pointing-Pointer Chemical delithiaition was performed by using NO{sub 2}BF{sub 4} oxidizing agent. Black-Right-Pointing-Pointer The rhombohedral symmetry was preserved upon lithium removal. Black-Right-Pointing-Pointer Lithium extraction leads to Ni{sup 2+} oxidation to Ni{sup 4+} followed by Co{sup 3+} oxidation. Black-Right-Pointing-Pointer The EPR narr…
Magnetic and structural approach for understanding the electrochemical behavior of LiNi0.33Co0.33Mn0.33O2 positive electrode material
Abstract A systematic study has been performed to investigate the structural and magnetic changes in LiNi 0.33 Mn 0.33 Co 0.33 O 2 , a member of the LiNi y Mn y Co 1–2 y O 2 series, upon chemical lithium deintercalation. Structural characterization of the chemically delithiated Li x Ni 0.33 Mn 0.33 Co 0.33 O 2 samples indicates that the initial rhombohedral symmetry (α-NaFeO 2 type structure) is maintained in the whole 0.3 ≤ x ≤ 1.0 composition range. Less than 1% variation in the hexagonal unit cell volume was evidenced showing a good structural stability of this sample. SEM pictures of the delithiated phases confirm this stability. Indeed, the particle size average undergoes a small dec…
A review on LiNixCo1−2xMnxO2 (0.1 ≤ x ≤ 0.33) cathode materials for rechargeable Li-ion batteries
Abstract Electrochemical and physical properties of LiNixCo1−2xMnxO2 (0.1 ≤ x ≤ 0.33) electrode materials prepared by self-combustion were investigated. Pure LiNixCo1−2xMnxO2 (x = 0.1, 0.2, 0.33) materials with single phase and R-3 m layered structure were obtained as confirmed by X-ray diffraction. Energy Dispersive Spectroscopy, Scanning Electron Microscopy are commonly used to determine the chemical composition and the distribution of particle size of the three samples. The electrochemical performances of the samples were measured at different current rates in the 3–4.5 V potential range. The studied materials exhibit good discharge capacity. The magnetic susceptibility measurements and …