文献类型：期刊文献

英文题名：Fracture behaviour of NCM polycrystalline particles in lithium-ion batteries under extreme conditions

作者：Chen, Ying[1];Yao, Yiming[1];Yao, Zhiheng[1];Li, Wei[2];Shen, Xiaojie[2];Song, Jinyang[2];Luan, Weiling[1];Chen, Haofeng[1,3];Tu, Shan-tung[1];Wu, Kai[2]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Adv Battery Syst & Safety CPCIF, Shanghai 200237, Peoples R China;[2]Contemporary Amperex Technol Co Ltd, Ningde 352100, Peoples R China;[3]Univ Strathclyde, Dept Mech & Aerosp Engn, Glasgow G1 1XJ, Scotland

年份：2025

卷号：141

外文期刊名：NANO ENERGY

收录：;EI(收录号：20251918372973);WOS:【SCI-EXPANDED(收录号:WOS:001510385100001)】；

基金：The authors gratefully acknowledge the support from the National Natural Science Foundation of China (52375144 and 52205153) , Shanghai Pujiang Programme (23PJD019) during the course of this work.

语种：英文

外文关键词：Fracture behaviour; NCM polycrystalline particle; Extreme condition; Diffusion-induced stress; Lithium-ion battery; Cracking

摘要：Understanding the fracture behavior of nickel-rich layered LiNixCoyMn1-x-yO2 (NCM) cathode materials under extreme operating conditions is crucial for improving the reliability of lithium-ion batteries (LIBs). At present, the failure mechanism of widely used NCM cathode materials under the condition of high cut-off voltage and fast charging rate are still not comprehensively understood, making the established chemo-mechanical mechanism inaccurate. In this study, the crack evolution of NCM polycrystalline particles under extreme conditions are investigated using a combination of quasi in-situ SEM, in-situ XRD and finite element simulations. Three representative crack patterns of penetrating-type, radiating-type and fragmented-type cracks are identified, and the formation mechanisms are comprehensively clarified. It is revealed that weak grain boundaries at the NCM polycrystalline particle center play a crucial role in rapid cracking and influence crack morphology. Furthermore, in-situ XRD characterization are conducted to claim the cause of diffusion-induced stress in NCM particles. Both the severe expansion/contraction of primary particles under high cut-off voltage conditions and strain mismatch from uneven lithium-ion distribution during fast charging, drives mechanical degradation of NCM polycrystalline particle. Numerical simulations incorporating cohesive zone models confirm the influence of defect distribution and material strength on crack propagation. Moreover, rapid cracking behaviors including intergranular cracks, intragranular and transgranular cracks are analyzed, which are associated with the complex stress field distribution. Based on the obtained failure mechanism of NCM polycrystalline particles, material optimization strategies are suggested to enhance the mechanical strength and cycling stability of NCM materials, offering a theoretical basis for guiding the design and synthesis of cathode materials and improving the performance and life of LIBs.