Low-temperature synthesis of amorphous LiF/Li₃BO₃ interfaces with F, B co-doped subsurface for long-cycling and high-rate Ni-rich cathodes

Abstract

Ni-rich layered oxide cathode materials, such as LiNi_0.8Co_0.1Mn_0.1O₂ (NCM), are promising candidates for high-performance lithium-ion batteries (LIBs) due to their high energy density and cost-effectiveness. However, structural degradation and interfacial instability hinder their cycling stability. In this study, we introduce a low-temperature modification strategy to construct an amorphous LiF/Li₃BO₃ interface with an F, B co-doped subsurface on NCM cathodes. This dual modification enhances bulk structural stability and accelerates interfacial ion transport kinetics. As a result, the LiF/Li₃BO₃-modified NCM cathode achieves a high specific capacity of 205.4 mAh·g⁻¹ within a voltage window of 2.8–4.5 V at 1 C. Remarkably, it maintains 70.6 % capacity retention after 500 cycles, a substantial improvement over the unmodified NCM, which retains only 34.2 %. Moreover, the modified cathode exhibits excellent rate capability, delivering high capacities of 185.5 mAh·g⁻¹ at 5 C and 172.8 mAh·g⁻¹ at 10 C. This work offers a novel low-temperature approach to tailor both the bulk and surface microstructures of Ni-rich cathodes, paving the way for high-energy-density and long-life lithium-ion batteries.