Dependence of Initial Capacity Irreversibility on Oxygen Framework Chemistry in Li-Rich Layered Cathode Oxides

扫码查看

原文链接

NETL
NSTL
万方数据

外文摘要：The undesirable capacity loss after first cycle is universal among layered cathode materials,which results in the capacity and energy decay.The key to resolving this obstacle lies in understanding the effect and origin of specific active Li sites during discharge process.In this study,focusing on Ah-level pouch cells for reliability,an ultrahigh initial Coulombic efficiency(96.1％)is achieved in an archetypical Li-rich layered oxide material.Combining the structure and electrochemistry analysis,we demonstrate that the achievement of high-capacity reversibility is a kinetic effect,primarily related to the sluggish Li mobility during oxygen reduction.Activating oxygen reduction through small density would induce the oxygen framework contraction,which,according to Pauli repulsion,imposes a great repulsive force to hinder the transport of tetrahedral Li.The tetrahedral Li storage upon deep oxygen reduction is experimentally visualized and,more importantly,contributes to 6％Coulombic efficiency enhancement as well as 10％energy density improvement for pouch cells,which shows great potentials breaking through the capacity and energy limitation imposed by intercalation chemistry.

外文关键词：

irreversible capacity lossLi transport kineticsLi-rich layered oxidesoxygen framework chemistrytetrahedral Li

作者：

Xiao Li、Yibin Zhang、Bao Qiu、Guoxin Chen、Yuhuan Zhou、Qingwen Gu、Zhaoping Liu

展开 >

作者单位：

Ningbo Institute of Materials Technology & Engineering(NIMTE),Chinese Academy of Sciences,Ningbo 315201,China

College of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences(UCAS),Beijing 100049,China

基金：

National Natural Science Foundation of China"Lingyan"Research and Development Plan of Zhejiang ProvinceLow Cost Cathode MaterialNatural Science Foundation of NingboYouth Innovation Promotion Association of Chinese Academy of Sciences

项目编号：

522722532022C01071TC220H06P202003N40302022299

出版年：

2024

DOI：

10.1002/eem2.12722

能源与环境材料(英文)

ISSN：

年,卷(期)：2024.7(5)