Electrochemical impedance study of Li-ion insertion into mesocarbon microbead single particle electrode: Part II. Disordered carbon

• Published in: Electrochimica acta Vol. 47; no. 6; pp. 933 - 938
• Main Authors: Dokko, K, Fujita, Y, Mohamedi, M, Umeda, M, Uchida 1, I, Selman 1, J.R
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 14-12-2001; Elsevier
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Disordered carbon; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Lithium batteries; Microelectrode; Single particle; Solid electrolyte interphase; Microelectrode; Lithium batteries; Solid electrolyte interphase; Disordered carbon; Single particle; Electrode impedance; Lithium Ions; Organic carbonate; Insertion; Electrode material; Carbon; Transport process; Organic solvent; Equivalent circuit; Kinetics; Diffusion coefficient
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/S0013-4686(01)00809-X

Electrochemical impedance spectroscopy (EIS) was applied for a single mesocarbon microbead (heat-treated at 1000
°C) of 30 μm diameter during Li-ion insertion and extraction using a stainless tip-microelectrode in the electrolyte of 1 M LiClO
4/propylene carbonate+ethylene carbonate. Obtained spectra were analyzed with an equivalent circuit model. Kinetic parameters such as the charge transfer resistance, and the apparent chemical diffusion coefficient of Li-ion in the particle were evaluated without interference of organic binders. The charge transfer resistance decreased and chemical diffusion coefficient of Li-ion increased as the electrode potential was made more negative. The chemical diffusion coefficient varied within 10
−12–10
−6 cm
2 s
−1.