Structural Relaxation of Lix(Ni0.874Co0.090Al0.036)O₂ after Lithium Extraction down to x = 0.12

Jian Kang; Shigeomi Takai; Takeshi Yabutsuka; Takeshi Yao

doi:10.3390/ma11081299

Structural Relaxation of Li_x(Ni_0.874Co_0.090Al_0.036)O₂ after Lithium Extraction down to x = 0.12

Materials (Basel). 2018 Jul 27;11(8):1299. doi: 10.3390/ma11081299.

Authors

Jian Kang¹, Shigeomi Takai², Takeshi Yabutsuka³, Takeshi Yao^{4

5}

Affiliations

¹ Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan. kang.jian.77w@st.kyoto-u.ac.jp.
² Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan. stakai@energy.kyoto-u.ac.jp.
³ Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan. yabutsuka@energy.kyoto-u.ac.jp.
⁴ Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan. t_yao@hera.eonet.ne.jp.
⁵ National Institute of Technology, Kagawa College, Chokushi-cho, Takamatsu, Kagawa 761-8058, Japan. t_yao@hera.eonet.ne.jp.

Abstract

A structural relaxation study has been carried out on Li_x(Ni_0.874Co_0.090Al_0.036)O₂ after the electrochemical lithium was extraction down to x = 0.12. These relaxation analyses have been carried out using X-ray diffraction coupled with the Rietveld analysis, assuming two phases (H2 and H3) and co-existence with R3¯m symmetry. The mole fraction of the H3 phase seemed not to vary largely during the relaxation time. As for the lattice constants, both H2 and H3 phases gradually increased the a-axis with the relaxation time. On the other hand, H2 and H3 phases increased and decreased the c-axis, respectively. The results are compared with that of previously reported Ni-rich NCA.

Keywords: NCA; lithium ion battery; relaxation analysis.