Fabrication of scandium-doped lithium manganese oxide as a high-rate capability cathode material for lithium energy storage

Abstract

Spinel lithium manganese oxide (LiMn2O4) has been widely used as the commercial cathode material for lithium-ion batteries due to its low cost, environmental benignity as well as high-energy density. Nevertheless, LiMn2O4 electrode suffers from a capacity fading during the cycling process, which can be attributed to the manganese dissolution into the electrolyte solution. In this study, the Sc3+-doped LiMn2-xScxO4 (x = 0, 0.03, 0.06 and 0.09) cathode materials have been designed and fabricated using a high-temperature solid-state approach. Structural characterization using XRD indicates that an appropriate amount of Sc3+-ion doping has no influence on the spinel structure of LiMn2O4 material. Morphological characterizations using SEM and TEM reveal that the Sc3+-ion doping can increase the particle size of LiMn2O4. Compared with the undoped LiMn2O4, the Sc3+-ion doped LiMn2-xScxO4 (x = 0.03, 0.06 and 0.09) electrodes exhibit better cycling stability when used as cathodes for lithium energy storage. Particularly, the obtained LiMn1.94Sc0.06O4 shows a stable cycling performance with only about 12.1% capacity loss over 300 cycles at 10 C.