Synergistic effect of B[sbnd]Nb co-modified to achieve crystal structure and interface tuning for Ni-rich cathode

Abstract

Nickel-rich cathode materials play a pivotal role in the functioning of lithium-ion batteries, but their crystal structure defects and surface side reactions significantly affect battery performance. This has slowed down the commercialization process of nickel-rich cathodes. To remedy these problems, a new strategy utilizing B and Nb for crystal structure and interface control of LiNi0.8Co0.1Mn0.1O2 (NCM811) is proposed in this study. The BNb modified cathode exhibits strong radial orientation and exposes a large number of active (003) lattice plane on the particle surface. This structural control reduces micro-cracks and accelerates lithium-ion diffusion kinetics. Additionally, the LiNbO3 coating effectively avoids immediate contact between secondary particles and the electrolyte, greatly alleviating side reactions. Consequently, the optimal cathode B-NCM@LNO5 modified cathode maintains a capacity retention of 86.71% after 200 cycles at 1 C, outperforming the original material (76.11% retention). Meanwhile, it demonstrates attractive rate capability of 158.4 mAhg−1 under 5 C. This research provides valuable insights for addressing anisotropic strain and interface compatibility issues in nickel-rich cathodes.