TOF-ERDA analysis on the effect of water for SEI formation in Li-ion batteries

(1) Toray Research Center Inc., 3-3-7, Sonoyama, Otsu, Shiga 520-0842, Japan
(2) Kyoto Prefectural University, 1-5, Hangi-cho, Sakyo-ku, Kyoto, Kyoto 606-8522, Japan
(3) The Wakasa Wan Energy Research Center, 64-52-1, Nagatani, Tsuruga, Fukui 914-0192, Japan
In the field of Li-ion batteries, extensive researches have been carried out to understand the process of solid electrolyte interphase (SEI) formation on electrode surfaces. In terms of acquiring depth profile, time of flight elastic recoil detection analysis (TOF-ERDA) is a promising method for the measurements of light elements, including H and Li, with better depth resolution [1-3]. Here we demonstrate TOF-ERDA analysis, to evaluate the effect of water in a cell for SEI formation.
 
Details of the TOF-ERDA experimental setup is presented in ref. [3]. In this work, we used two time detectors in order to improve the time resolution. The time detectors are positioned at a front and a rear of the flight pass, using carbon foils with a thickness of 3 mg/cm2 (front) and 10 mg/cm2 (rear), respectively.

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[3] K. Yasuda, C. Batchuluun, R. Ishigami, S. Hibi, Nucl. Instr. and Meth. B 268 (2010) 2023.