In situ synchrotron X-ray studies on copper–nickel 5 V Mn oxide spinel cathodes for Li-ion batteries

Synthesis and Electrochemical Performance of Reduced Graphene Oxide/AlPO4-coated LiMn1.5Ni0.5O4for Lithium-ion Batteries

“…6 However, LMNO reveals poor electrochemical performance. The capacity fading phenomenon is considered to be due to the large lattice strain upon cycling since it involves the formation of three cubic phases with a large lattice parameter difference during the charge/discharge process in addition to the corrosion reaction between the cathode surface and the electrolyte at the high operating voltage of ~5 V. [7][8][9] Some of the partial substitution of Mn and Ni in LMNO by other elements such as Mg, Cr, Fe, Co, Mo, W, and Tb has been pursued to enhance the electrochemical performance.…”

High Voltage Cathode Materials

“…4 V for LiNi 0.5 Mn 1.5 O 4−δ is attributed to the Mn 3+ /Mn 4+ couple due to the existence of a small amount of Mn 3+ ions resulting from the charge compensation of oxygen loss. The crystal structure of LiMn 1.5 Ni 0.5 O 4 has been determined by various techniques including XRD [35,36], neutron diffraction [36,37], XAFS [38], XANES [39], ex situ electron diffraction [36], in situ synchrotron X-ray absorption (XAS) [40], Raman scattering spectroscopy [19,25,41], ex situ Fourier transform infrared (FTIR) spectroscopy [25,[41][42][43] and in situ FTIR [44]. Raman and FTIR spectroscopy have been proven to be effective tools in differentiating the ordered versus disordered LNM structures; the sample with cationic ordering is known to exhibit characteristic infrared bands at 650, 465 and 430 cm −1 [43].…”

Electrochemical Behavior of Surface-Fluorinated Cathode Materials for Lithium Ion Battery

“…LiNi 0.5 Mn 1.5 O 4 spinel exhibits the potential plateau at ∼4.7 V in the charge/discharge curves due to the presence of a Ni 2+ /Ni 3+ and Ni 3+ /Ni 4+ redox pairs [42,43]. LiM x Mn 2 − x O 4 suffers from poor cycling performance, which is believed to be caused by the large lattice strain during cycling [44,45], and the decomposition of electrolyte by the high operating voltage [46]. In addition, the synthesis of LiNi x Mn 2-x O 4 often encounters the formation of NiO impurity.…”