Using High-Entropy Configuration Strategy to Design Spinel Lithium Manganate Cathodes with Remarkable Electrochemical Performance

Abstract

Owing to its abundant manganese source, high operating voltage, and good ionic diffusivity attributed to its 3D Li-ion diffusion channels. Spinel LiMn₂O₄ is considered a promising low-cost positive electrode material in the context of reducing scarce elements such as cobalt and nickel from advanced lithium-ion batteries. However, the rapid capacity degradation and inadequate rate capabilities induced by the Jahn–Teller distortion and the manganese dissolution have limited the large-scale adoption of spinel LiMn₂O₄ for decades. In this study, LiMn_1.98Mg_0.005Ti_0.005Sb_0.005Ce_0.005O₄ spinel positive electrode material (HE-LMO) with remarkable interfacial structural and cycling stability is developed based on a complex concentrated doping strategy. The initial discharge capacity and capacity retention of the electrode of HE-LMO are 111.51 mAh g⁻¹ and 90.55% after 500 cycles at 1 C. The as-prepared HE-LMO displays favorable cycling stability, significantly surpassing the pristine sample. Furthermore, theoretical calculations strongly support the above finding. HE-LMO has a higher and more continuous density of states at the Fermi energy level and more robust bonded states of the electrons among the Mn─O atom pairs. This research contributes to the field of high-entropy doping modification and establishes a facile strategy for designing advanced spinel manganese-based lithium-ion batteries (LIBs).