Co-doping aluminum and boron enhances the stability and electrochemical properties of nickel-rich cathode materials for lithium-ion batteries

Enhancement of the performance of lithium-ion batteries is a critical strategy for addressing the challenges associated with cost and raw materials. By doping boron (B), aluminum (Al), and aluminum/boron (Al/B) utilizing the sol-gel method, we demonstrate a substantial improvement in the cycling performance of Ni-rich lithium nickel manganese cobalt oxide (NMC) as an electrode. While the initial specific capacitance of the doped samples may be lower than that of the pristine NMC, these samples demonstrate a notable increase in specific capacitance during subsequent cycles, reaching a peak around the 10^th cycle and nearing the highest specific capacitance observed in NMC cathodes. We show that the B-doped NMC, Al-doped NMC, and Al/B co-doped NMC exhibit exceptional cycling performance, retaining approximately 68-76% of their initial specific capacitance after 150 cycles at a current density of 25 mA g^-1, which is far superior to the ability to maintain about 32.8% of the initial specific capacitance of the pristine NMC. A comprehensive analysis of the synthesized materials' characterization and electrochemical properties, alongside density functional theory simulations and experimental observations, underscores the critical role of doping elements in improving overall electrochemical performance. These findings highlight advancements in high-quality cathode materials for lithium-ion batteries, paving the way for future energy storage improvements.