TY  - JOUR
AU  - BAI, Zhaowen
AU  - Kandasamy, Subash
AU  - Wang, Wei
AU  - Zhou, Rui
AU  - Zhang, Zhenjie
AU  - Wang, Xuefeng
AU  - Liu, Jiatu
AU  - Wang, Zhenbin
AU  - Chen, Guohua
AU  - Kong, Qingyu
AU  - Li, Tianyi
AU  - Ren, Yang
TI  - Ni Migration-Induced Strain and Phase Segregation in LiNiO<sub>2</sub> Cathodes
JO  - ACS nano
VL  - 19
IS  - 20
SN  - 1936-0851
CY  - Washington, DC
PB  - Soc.
M1  - PUBDB-2025-02396
SP  - 19364 - 19372
PY  - 2025
N1  - Waiting for fulltext
AB  - High-nickel layered oxides are promising cathode materials for next-generation lithium-ion batteries due to their high energy density, but their structural instability at high voltages remains a critical challenge. This study investigates how Ni migration influences phase segregation, Li/Ni antisite defect accumulation, and mechanical degradation in LiNiO<sub>2</sub> (LNO) through a combination of synchrotron X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), transmission electron microscopy (TEM), and density functional theory (DFT) calculations. The results reveal that at high voltages, Ni migrates into tetrahedral sites, leading to the formation of coexisting R3̅m phases with distinct lattice behaviors. This phase segregation induces inhomogeneous lithium distribution, internal stress, and strain accumulation, ultimately promoting microcrack formation and accelerating structural degradation. While Ni migration is partially reversible upon discharge, continuous cycling leads to the progressive accumulation of Li/Ni antisite defects, which disrupt Li-ion transport and further destabilize the structure. The findings describe the role of bulk Ni migration in phase segregation, linking atomic-scale lattice distortions to long-term performance limitations in high-Ni cathodes. These insights suggest strategies such as selective doping to mitigate Ni migration and improve the structural stability.
LB  - PUB:(DE-HGF)16
DO  - DOI:10.1021/acsnano.5c03288
UR  - https://bib-pubdb1.desy.de/record/633794
ER  -