On the key role of Dy 3+ in spinel LiMn 2 O 4 cathodes for Li-ion rechargeable batteries

A series of dysprosium (Dy) doped LiMn2O4 based spinel cathode materials, LiMn2 − xDyxO4 (x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) for Li ion rechargeable battery application were synthesized by sol-gel process. The physical properties were explored through X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray diffraction (EDX), field emission scanning electron microscopy (FE-SEM), and micro-Raman spectroscopy. Swagelok cell configurations were used for electrochemical characterizations e.g. cyclic voltammetry, rate performance, cycleability and AC impedance. The doping amount of dysprosium has improved the surface morphology (particle size < 1 μm) by reducing particle size. The Dy(0.02) showed improved capacity of 122, 72 and 78 mAh g− 1 at C/10, C/5 and C/10 (recv.) respectively. The lower impedance of Dy(0.02) in comparison of pristine and other derivatives of synthesized cathode materials also supports these outcome.