Microcrack generation and modification of Ni-rich cathodes for Li-ion batteries: A review

Ni-rich transition metal layered oxides as one of the most promising cathodes for Li-ion batteries possess discernible advantages such as high energy density and discharge capacity. Despite their superiority, Ni-rich cathodes suffer from severe microcracks within the secondary particles, particularly when the nickel content exceeds 80%, which causes liquid electrolyte penetrates the interior of secondary particles and reacts with more active materials, leading to rapid degradation of cell performance. Therefore, increasing researches focus on understanding the causes of microcracks generation and overcoming particle cracking. Herein, the intrinsic origins of microcracks in Ni-rich cathodes, together with effective modification strategies for suppressing the nucleation and propagation of microcracks are reviewed. • The in-depth understanding of microcrack generation is established. • Modification strategies of Ni-rich cathode for enabling structural stability. • Perspectives toward designing the crack-free Ni-rich cathode are provided.