Unveiling the Influence of Formation Voltage on Li‐Rich Layered Oxide Cathode
Abstract
Abstract Lithium‐rich layered oxide (LRLO) cathodes are recognized for their high energy densities, primarily driven by oxygen‐related anionic redox activities, yet substantial activation of this process simultaneously induces structural instability. The typical voltage range in academic studies spans 2.0–4.8 V. Although 2.5–4.5 V are generally considered in industrial applications for enhanced capacity retention and electrolyte compatibility, this moderate voltage window leads to reduced capacity. To address energy density limitations, several top battery suppliers propose to separately increase the formation voltage during the initial cycle to enhance capacity, while other companies (e.g., Contemporary Amperex Technology Co., Ltd., CATL) claim that this high‐voltage formation protocol would exacerbate cycling capacity fading. Herein, we systemically demonstrate that high‐voltage formation promotes substantial Li + extraction from the transition metal (TM) layers, creating vacancies (in TM layer) that drive in‐plane TM migration. This migration triggers a transformation in the OM 6 (M, cation) configuration from O4 (OLi x TM 2 ) to O5 (OLi y TM 1 ). Such evolution simultaneously enhances both anionic and cationic redox activity, collectively boosting capacity. Nonetheless, the induced in‐plane TM migration would further aggravate out‐of‐plane TM migration, leading to progressive structural degradation, which has been elucidated as the main reason for cycling capacity fading.
Article Details
Authors (22)
Kang Zhang
Qi Biodesign, Beijing, China.
Yichun Zheng
School of Materials Sun Yat‐sen University Shenzhen P. R. China
Jianhua Yin
State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China
Yawen Yan
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Yilong Chen
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Department of Chemistry, College of Chemistry and Chemical Engineering
Yuan Tian
Yizhen Huang
Lianpeng Li
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China
Jiyuan Xue
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Wen Jiao
Materials Innovation Department (MID) Contemporary Amperex Technology Co. Limited (CATL) Ningde 352100 P.R. China
Na Liu
Lirong Zheng
Huan Huang
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics
Jing Zhang
Deniz Wong
Helmholtz‐Center Berlin for Materials and Energy Hahn‐Meitner‐Platz 1 Berlin 14109 Germany
Bodry Tegomo Chiogo
Helmholtz‐Center Berlin for Materials and Energy Hahn‐Meitner‐Platz 1 Berlin 14109 Germany
Christian Schulz
Yang Sun
Chongheng Shen
Qingsong Wang
Yu Qiao
Shi‐Gang Sun
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China