Origin of Double Ligand Holes and Abnormal Inductive Effect of <i>n</i> p <sup>6</sup> Elements in Ni‐rich Cathodes
Abstract Ni‐rich cathodes stand out for their ability to achieve high energy density in Li‐ion batteries. However, their long‐term cycling stability is challenged by excessive oxygen redox activity, the fundamental atomic‐scale behavior of which remains poorly understood—particularly the nature of oxygen double ligand hole states and their suppression. This study demonstrates that Jahn–Teller distortion promotes unexpected intralayer O─O pairing, coupled with Ni─O hybridization, leading to the formation of double ligand holes in LiNiO 2 and oxygen evolution at high state‐of‐charge (SoC). These intralayer O─O pairs are visualized by 4D scanning transmission electron microscopy and identified as peroxo‐like species with an average O─O distance of 2.428 Å at 60% SoC. Meanwhile, substitution with elements such as Al 3+ and Sc 3+ , which possess low electronegativity and an n p 6 electron configuration, induces an abnormal inductive effect that deviates from conventional electronegativity‐based frameworks. This phenomenon is attributed to electron localization on lattice oxygen, which effectively prevents local lattice distortion and the accumulation of TM─O and O─O ligand holes. These findings establish a fundamental correlation between structural deformation and ligand hole states, advancing the conceptual framework for Ni‐rich cathode design beyond conventional molecular orbital theory and electronegativity‐guided substitution strategies.
Authors
- Jaesub Kwon (ORCID: https://orcid.org/0000-0002-3439-2239)
- Jong‐Heon Lim (ORCID: https://orcid.org/0000-0002-7555-3721)
- Kyoung Eun Lee (ORCID: https://orcid.org/0000-0003-1110-8933)
- H. Jang
- Kyu‐Young Park (ORCID: https://orcid.org/0000-0001-9560-8526)
- Eunseong Choi
- Yong‐Tae Kim (ORCID: https://orcid.org/0000-0001-9232-6558)
- Youngsu Lee
- C.G. Hwang
Institutions
- Pohang University of Science and Technology (KR)
- Samsung (South Korea) (KR)
Publication Details
- Journal
- Advanced Functional Materials
- Published
- 2025-10-14
- DOI
- https://doi.org/10.1002/adfm.202512501
- Primary Topic
- Advancements in Battery Materials
- Type
- article
- Field-Weighted Citation Impact
- 0.00