Multi-shelled LiMn1.95Co0.05O4 cages with a tunable Mn oxidation state for ultra-high lithium storage†
Superior electrochemical performance of LiMn2O4 is considered to be one of the most important properties for lithium-ion batteries (LIBs). This paper presents an extremely high performance cathode material, multi-shelled LiMn1.95Co0.05O4 cages, which are created using a sucrose template. A small amount of Co substitution uniformly in a bulk material not only tunes Mn3+ in the minority with bulk stability improving, but can also accommodate specific capacity. In addition, the unique caged structure enhances Li+ diffusion and electrolyte penetration, leading to an outstanding rate capability. The as-synthesized cathode material exhibits a very high capacity of 154.4 mA h g−1, and retains a high value of 136.7 mA h g−1 after 500 cycles. The present work investigated the combined effect of a tunable average Mn oxidation state and unique multi-shelled cages in a controllable aerosol process.