Investigation of solid electrolyte interfacial layer development during continuous cycling using ac impedance spectra and micro-structural analysis

• Published in: Journal of power sources Vol. 189; no. 1; pp. 66 - 71
• Main Authors: Moss, P.L., Au, G., Plichta, E.J., Zheng, J.P.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-04-2009; Elsevier
• Subjects: ac Impedance; Applied sciences; Battery; Charge; Cycles; Cycling performance; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrodes; Electrolytic cells; Exact sciences and technology; Impedance; Lithium polymer battery; Scanning electron microscopy; Solid-electrolyte interfacial layer; Spectra; Solid-electrolyte interfacial layer; ac Impedance; Cycling performance; Lithium polymer battery; Scanning electron microscopy; Particle size; Solid electrolyte; Film formation; Secondary cell; Dissolution; Discharge charge cycle; Lithium battery; Equivalent circuit; Impedance; Performance; Passivation; Electrochemical impedance spectroscopy
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2008.11.048

The formation of passivating surface films on the electrodes of a lithium-ion polymer battery was investigated at various cycling state using ac impedance spectroscopy and scanning electron microscopy (SEM). A sealed commercial cell (Sony Co.) with a nominal capacity of 840
mAh was used for the experiment. An equivalent circuit used to model the impedance spectra show that, with continuous cycling there is a relatively large increase in the interfacial impedance and charge transfer resistances after a few hundred charge–discharge cycles. It was observed that the cell capacity decrease with increase cell impedance. SEM analysis on the electrodes shows that during continuous charge–discharge cycling, the deposition of sub-micro-size particles and dissolution of surface films on the graphite surface. This observation is consistent with increase in cell impedance as a function of charge/discharge cycling.