Reaction Behavior of a Silicide Electrode with Lithium in an Ionic-Liquid Electrolyte

Yasuhiro Domi; Hiroyuki Usui; Kai Sugimoto; Kazuma Gotoh; Kei Nishikawa; Hiroki Sakaguchi

doi:10.1021/acsomega.0c03357

Reaction Behavior of a Silicide Electrode with Lithium in an Ionic-Liquid Electrolyte

ACS Omega. 2020 Aug 26;5(35):22631-22636. doi: 10.1021/acsomega.0c03357. eCollection 2020 Sep 8.

Authors

Yasuhiro Domi^{1

2}, Hiroyuki Usui^{1

2}, Kai Sugimoto^{3

2}, Kazuma Gotoh^{4

5}, Kei Nishikawa⁶, Hiroki Sakaguchi^{1

2}

Affiliations

¹ Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Minami 4-101, Koyama-cho, Tottori 680-8552, Japan.
² Center for Research on Green Sustainable Chemistry, Tottori University, Minami 4-101, Koyama-cho, Tottori 680-8552, Japan.
³ Course of Chemistry and Biotechnology, Department of Engineering, Graduate School of Sustainability Science, Tottori University, Minami 4-101, Koyama-cho, Tottori 680-8552, Japan.
⁴ Graduate School of Natural Science & Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
⁵ Element Strategy Initiative for Catalysis and Batteries (ESICB), Kyoto University, Nishikyo-ku, Kyoto 615-8245, Japan.
⁶ International Center of Young Scientists, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan.

Abstract

Silicides are attractive novel active materials for use in the negative-electrodes of next-generation lithium-ion batteries that use certain ionic-liquid electrolytes; however, the reaction mechanism of the above combination is yet to be clarified. Possible reactions at the silicide electrode are as follows: deposition and dissolution of Li metal on the electrode, lithiation and delithiation of Si, which would result from the phase separation of the silicide, and alloying and dealloying of the silicide with Li. Herein, we examined these possibilities using various analysis methods. The results revealed that the lithiation and delithiation of silicide occurred.