Improved electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2 by Mg doping for lithium ion battery cathode material

Abstract

Li-rich, Mn-based layered material is one of the most promising cathode materials for next-generation lithium ion batteries. However, this material is subject to severe capacity fading and poor rate capability. When Li was replaced with Mg, the electrochemical performance of the material improved. Structural and elemental analyses indicate an expansion of the unit cell as a result of Mg doping, while the crystal structure remained unaffected. Higher specific capacity and better rate capability with more stable cycling performance were obtained from a sample of Li_1.17Mg_0.03Mn_0.54Ni_0.13Co_0.13O₂ as compared with other samples that were either Mg-free or with Mg atomic content beyond 0.03.