Spinel LiMn2-xNixO4 cathode materials for high energy density lithium ion rechargeable batteries.

The practical limitations of fully lithium ion insertion and extraction into LiMn₂O₄ cathode structure without any structural instability make it unsuitable in commercial Li-ion rechargeable batteries. In this work, we showed that those partially substituted by Ni, i.e., LiMn_2-xNi_xO₄ (0≤x≤0.5), prepared by sol-gel technique, could be used as a potential candidate for high energy density and high voltage Li-ion battery applications with superior rate capabilities. The improved structural stability of the cathode was probed by x-ray diffraction and micro-Raman spectroscopy. The density-functional theoretical calculations were employed to identify the minimum energy needed for Li⁺ diffusion pathway and activation energy in the spinel framework with different Ni ion concentrations. Our results showed significant enhancement in the properties with 25 at. % of Ni solid-solution doping in LiMn₂O₄ host and the experimental results are in line with the theoretical computations. [ABSTRACT FROM AUTHOR]