Oxygen-redox reactions in LiCoO2 cathode without O-O bonding during charge-discharge

被引：97

作者：

Hu, Enyuan ^{[1
]}

Li, Qinghao ^{[2
]}

Wang, Xuelong ^{[1
]}

Meng, Fanqi ^{[2
]}

Liu, Jue ^{[4
]}

Zhang, Jie-Nan ^{[2
]}

Page, Katharine ^{[4
]}

Xu, Wenqian ^{[5
]}

Gu, Lin ^{[2
]}

Xiao, Ruijuan ^{[2
]}

Li, Hong ^{[2
]}

Huang, Xuejie ^{[2
]}

Chen, Liquan ^{[2
]}

Yang, Wanli ^{[3
]}

Yu, Xiqian ^{[2
]}

Yang, Xiao-Qing ^{[1
]}

机构：

[1] Brookhaven Natl Lab, Chem Div, Upton, NY 11973 USA

[2] Chinese Acad Sci, Beijing Adv Innovat Ctr Mat Genome Engn, Inst Phys, Beijing 100190, Peoples R China

[3] Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA

[4] Oak Ridge Natl Lab, Neutron Scattering Div, Oak Ridge, TN 37831 USA

[5] Argonne Natl Lab, Xray Sci Div, Argonne, IL 60439 USA

来源：

JOULE | 2021年 / 5卷 / 03期

基金：

国家重点研发计划;

关键词：

ANIONIC REDOX; HIGH-CAPACITY; PLANE-WAVE; VOLTAGE HYSTERESIS; ION BATTERIES; LI; LITHIUM; OXIDE; TRANSITION; VISUALIZATION;

D O I：

10.1016/j.joule.2021.01.006

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Oxygen activity in highly delithiated LiCoO2 is critical to fully utilizing the energy density of this high-tap-density cathode but still lacks a clear understanding. In this work, we combined the results of several experimental techniques, especially resonant inelastic Xray scattering (RIXS) and neutron pair distribution function (NPDF) analysis, together with theoretical calculations to study this topic. Our results conclude that oxygen redox takes place globally in the lattice, rather than forming localized dimerization as previously thought. RIXS results directly reveal the reversible oxygen redox, and NPDF results show that the O-O pair distance is considerably shortened in the highly delithiated LiCoO2. Theoretical calculations indicate that no O-O bonding is formed in LiCoO2, in sharp contrast to the lithium-rich system in which O-O bonding does form. These results provide the rationale for achieving a reversible deep delithiation and high energy density for LiCoO2-based electrodes.

引用

页码：720 / 736

页数：17

共 62 条

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