Dynamic Evolution of a Cathode Interphase Layer at the Surface of LiNi0.5Co0.2Mn0.3O2 in Quasi-Solid-State Lithium Batteries

Hui-Juan Guo; Huai-Xiang Wang; Yu-Jie Guo; Gui-Xian Liu; Jing Wan; Yue-Xian Song; Xin-An Yang; Fei-Fei Jia; Fu-Yi Wang; Yu-Guo Guo; Rui Wen; Li-Jun Wan

doi:10.1021/jacs.0c09602

Dynamic Evolution of a Cathode Interphase Layer at the Surface of LiNi_0.5Co_0.2Mn_0.3O₂ in Quasi-Solid-State Lithium Batteries

J Am Chem Soc. 2020 Dec 9;142(49):20752-20762. doi: 10.1021/jacs.0c09602. Epub 2020 Nov 29.

Authors

Hui-Juan Guo^{1

2}, Huai-Xiang Wang^{2

3}, Yu-Jie Guo^{1

2}, Gui-Xian Liu^{1

2}, Jing Wan^{1

2}, Yue-Xian Song^{1

2}, Xin-An Yang^{2

3}, Fei-Fei Jia⁴, Fu-Yi Wang^{2

4}, Yu-Guo Guo^{1

2

5}, Rui Wen^{1

2

5}, Li-Jun Wan^{1

2}

Affiliations

¹ CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, and Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
² University of Chinese Academy of Sciences, Beijing 100049/100190, P. R. China.
³ Laboratory for Advanced Materials and Electron Microscopy, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
⁴ CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing National Laboratory for Molecular Sciences, National Centre for Mass Spectrometry in Beijing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
⁵ Dongguan TAFEL New Energy Technology Company, Limited, Dongguan 523000, P. R. China.

PMID: 33249846
DOI: 10.1021/jacs.0c09602

Abstract

Intensive understanding of the surface mechanism of cathode materials, such as structural evolution and chemical and mechanical stability upon charging/discharging, is crucial to design advanced solid-state lithium batteries (SSLBs) of tomorrow. Here, via in situ atomic force microscopy monitoring, we explore the dynamic evolution process at the surface of LiNi_0.5Co_0.2Mn_0.3O₂ cathode particles inside a working SSLB. The dynamic formation process of the cathode interphase layer, with an inorganic-organic hybrid structure, was real-time imaged, as well as the evolution of its mechanical property by in situ scanning of the Derjaguin-Muller-Toporov modulus. Moreover, different components of the cathode interphase layer, such as LiF, Li₂CO₃, and specific organic species, were identified in detailat different stages of cycling, which can be directly correlated with the impedance buildup of the battery. In addition, the transition metal migration and the formation of new phases can further exacerbate the degradation of the SSLB. A relatively stable cathode interphase is key to improving the performance of SSLBs. Our findings provide deep insights into the dynamic evolution of surface morphology, chemical components and mechanical properties of the cathode interphase layer, which are pivotal for the performance optimization of SSLBs.