A new strategy to diminish the 4 V voltage plateau of LiNi0.5Mn1.5O4

Graphical abstract: The annealed sample LiNi0.5Mn1.5O4 cannot eliminate the 4-V voltage plateau completely. The Mg-doped compound LiNi0.5Mn1.45Mg0.05O4 can effectively diminish the 4 V voltage plateau during charge and discharge process. - Highlights: • Mg-doped compound LiNi0.5Mn1.45Mg0.05O4 was prepared. • The 4 V voltage plateau in the charge–discharge curves of LiNi0.5Mn1.45Mg0.05O4 was diminished. • Compound LiNi0.5Mn1.45Mg0.05O4 exhibited good electrochemical properties. - Abstract: As for spinel LiNi0.5Mn1.5O4, there is 4 V voltage plateau in the charge–discharge profiles. This voltage plateau can be reduced by an annealing process, however it is hard to avoid it completely. In this study, a new strategy of partial substitution for Mn by Mg is applied. There is no 4 V voltage plateau in the charge–discharge profiles of Mg-doped compound LiNi0.5Mn1.45Mg0.05O4. This compound exhibits good electrochemical properties which can be used as cathode material of lithium ion batteries. At 1 C rate, it can deliver a capacity of around 129 mAh g−1 and remain good cycle performance