Optimization of B2O3 coating process for NCA cathodes to achieve long-term stability for application in lithium ion batteries

Highlights: • LiNi_0.87Co_0.10Al_0.03O₂ (NCA) was prepared by optimizing the sintering temperature. • NCA surface was modified with B₂O₃ to improve its structural stability. • B₂O₃ was used to prevent the electrolyte corrosion of active materials. • B₂O₃-coated NCA exhibited structural stability after cycling. • B₂O₃-coated NCA exhibited a first discharge capacity of 184 mAh g⁻¹. Ni-rich cathodes exhibit rapid capacity degradation upon cycling; hence, the development of Ni-rich cathode materials with a stable electrochemical performance for use in next-generation lithium-ion batteries (LIBs) are extremely challenging. In this study, boron trioxide (B₂O₃)-modified LiNi_0.87Co_0.10Al_0.03O₂ (NCA) compounds with high charging–discharging structural stability were prepared using the Ni_0.88Co_0.095Al_0.025OH precursor for application in LIB cathodes. In addition, the sintering temperature of the NCA cathode material was optimized. B₂O₃ not only filled in the cracks that formed during the first sintering process but also effectively prevented the fragmentation and loss of cathode NCA particles during the charge–discharge process, thus improving their electrochemical properties. The coated particles exhibited sufficient structural integrity and did not exhibit severe cracking during the cycling process. The B2NCA3 cathode with 2.0 wt% B₂O₃ demonstrated sufficient cyclic stability and rate properties. It exhibited a high specific capacity of 184 mAh g⁻¹ and a capacity retention of 86% after 100 cycles at 0.2 C and 25 °C.