In situ diffuse reflectance spectroelectrochemistry of cathode materials in lithium-ion batteries

Authors

Lu-Lu Chen, State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
Hao-Ran Li, State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
Wei-Yi Liu, State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
Wei Wang, State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China

Document Type

Article

Corresponding Author(s)

Hao-Ran Li(lihaoran@smail.nju.edu.cn);
Wei Wang(wei.wang@nju.edu.cn)

Abstract

Developing in situ spectroelectrochemistry methods, which can provide detailed information about species transformation during electrochemical reactions, is very important for studying electrode reaction mechanisms and improving battery performance. Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials, thus in situ and in operando characterization techniques are particularly important. However, batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells, and there is still much room for battery characterization. In this work, a specially designed battery based on the structure of coin cells, whose upper cover was transparent, was constructed. With such a device, acquisition of diffuse reflectance spectra of electrode materials during charging and discharging was realized. This not only provided a simple measurement accessory for diffuse reflectance spectroscopy (DRS), but also complemented in situ characterization techniques for batteries. Taking commonly used cathode materials in lithium-ion batteries (LIBs), including LiFePO₄ (LFP), NCM811 and LiCoO₂ (LCO) as examples, we managed to find out the response relationships of different electrode materials to visible light of different wavelengths under ordinary reflectance illumination conditions. Heterogeneity of different cathode materials on interaction relationships with the lights of different wavelengths was also revealed. This work demonstrated the capability of guiding wavelength selection for different materials and assessing electrochemical performances of in situ diffuse reflectance spectroelectrochemistry. By combining electrochemistry with diffuse reflectance spectroscopy, this work made an effective complementary for spectroelectrochemistry.

Graphical Abstract

Keywords

Lithium-ion battery, Diffuse reflectance spectroelectrochemistry, In situ, Cathode materials

DOI

10.61558/2993-074X.3446

Online Date

2-23-2024

Recommended Citation

Lu-Lu Chen, Hao-Ran Li, Wei-Yi Liu, Wei Wang. In Situ Diffuse Reflectance Spectroelectrochemistry of Cathode Materials in Lithium-ion Batteries[J]. Journal of Electrochemistry, doi: 10.61558/2993-074X.3446.