Layered oxide cathodes with high Ni content promise high energy density and competitive cost for Li-ion batteries (LIBs). However, Ni-rich cathodes suffer from irreversible interface reconstruction and undesirable cracking with severe performance degradation upon long-term operation, especially at elevated temperatures. Herein, we demonstrate in situ surface engineering of Ni-rich cathodes to construct a dual ion/electron-conductive NiTiO₃ coating layer and Ti gradient doping (NC90–Ti@NTO) in parallel. The dual-modification synergy helps to build a thin, robust cathode–electrolyte interface with rapid Li-ion transport and enhanced reaction kinetics, and effectively prevents unfavorable crystalline phase transformation during long-term cycling under harsh environments. The optimized NC90–Ti@NTO delivers a high reversible capacity of 221.0 mAh g⁻¹ at 0.1C and 158.9 mAh g⁻¹ at 10C. Impressively, it exhibits a capacity retention of 88.4% at 25 ​°C after 500 cycles and 90.7% at 55 ​°C after 300 cycles in a pouch-type full battery. This finding provides viable clues for stabilizing the lattice and interfacial chemistry of Ni-rich cathodes to achieve durable LIBs with high energy density.

具有高 Ni 含量的层状氧化物正极为锂离子电池 (LIB) 带来了高能量密度和具有竞争力的成本。然而，富镍正极在长期运行时，尤其是在高温下，会出现不可逆的界面重构和不良开裂，性能严重下降。在此，我们展示了富镍阴极的原位表面工程，以构建双离子/电子导电 NiTiO ₃涂层和 Ti 梯度掺杂 (NC90–Ti@NTO) 平行。双改性协同作用有助于构建薄而坚固的正极-电解质界面，具有快速的锂离子传输和增强的反应动力学，并有效防止在恶劣环境下长期循环过程中不利的晶相转变。^{优化后的 NC90–Ti@NTO 在 0.1C 时提供 221.0 mAh g -1}的高可逆容量，在 10C 时提供 158.9 mAh g ^-1的高可逆容量。令人印象深刻的是，它在 25°C 下循环 500 次后的容量保持率为 88.4%，在 55°C 下循环 300 次后的容量保持率为 90.7%。这一发现为稳定富镍阴极的晶格和界面化学以实现具有高能量密度的耐用锂离子电池提供了可行的线索。