Multi-scale coupled failure mechanisms and stabilization strategies of high-nickel cathodes for next-generation high-energy lithium-ion batteries

Lithium-ion batteries (LIBs), featuring high energy density and long cycle life, have evolved into a critical technological pillar for global energy transition and dual-carbon target achievement, with fast-growing demand in electric transportation and grid-scale energy storage. High-nickel layered oxides (HNLOs) are widely recognized as one of the most promising cathode candidates for next-generation high-energy-density LIBs, owing to their superior reversible capacity, moderate operating voltage and low material cost. Nevertheless, the continuous increase in nickel content and cutting-off voltage triggers severe chemical, structural and mechanical instability, creating an inherent contradiction between high specific energy and long-term durability, which has become the core bottleneck for their large-scale commercialization. In this review, we systematically elaborate the multi-scale coupled failure mechanisms of HNLOs from a chemical-structural-mechanical perspective, including interfacial parasitic side reactions, irreversible lattice oxygen release, cation mixing-induced phase transformation, and chemo-mechanical failure. We comprehensively summarize state-of-the-art modification strategies, clarify their regulatory mechanisms and evolution from empirical optimization to rational design, identify critical gaps between lab-scale research and industrial application, and propose a holistic design philosophy for high-performance HNLOs. This review provides systematic theoretical and practical guidance for developing durable high-energy-density LIB cathodes.