実験報告書様式（一般利用課題・成果公開利用）（ ※本報告書は英語で記述してください。ただし、産業利用課題として採択されている方は日本語で記述していただいても結構です。 ）MLF Experimental Report

提出日 Date of Report
2013/08/11

課題番号 Project No.

装置責任者 Name of responsible person

2012B0187

Toru Ishigaki

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Structural analysis of oxide-coated high capacity layered oxides

BL20

Li1-y(MnaNibCoc)O2 positive electrode with Li de-intercalation

実施日 Date of Experiment/intercalation

2013/1/26-29

実験責任者名 Name of principal investigator
Hironori KOBAYASHI所属 Affiliation
National Institute of Advanced Industrial Science and Technology(AIST)
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
We used the layered oxides Li1.20-yMn0.55Ni0.16Co0.09O2 for neutron diffraction (ND) measurements.

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

Neutron diffraction data were taken in the range of 0.5 < d < 2.7 and at room temperature on a time-of-flight(TOF) neutron powder diffractometer of iMATERIA (BL20).

The pristine samples of ca. 3g and Li

de-intercalated samples of ca. 200 mg were contained in a vanadium cell, respectively.

Figure 1 shows the ND

patterns for Li1.20-yMn0.55Ni0.16Co0.09O2. The structure was refined using the ND data, the initial model beingthat of LiNi1/2Mn1/2O2 [1], with space group R3m and atomic positions Li1/Ni1 at 3a (0, 0, 0), Li2/Ni2/Co/Mnat 3b (0, 0, 0.5), and O at 6c (0, 0, z) where z ~ 0.25.

We clarified that the 3a site is occupied by a small

proportion of Ni and attempted to accurately determine both the distribution of cations on the 3a and 3b sites [1].
Therefore, the occupation parameters of Co and Mn at the 3b site were fixed and that of Ni2 at the 3b site wasrefined.

The total occupancies of both the 3b sites containing Li2/Ni2/Co/Mn and the 3a sites containing

Li1/Ni1 were constrained to be unity [Li2(g)+Ni2(g)+Co(g)+Mn(g)=1 and Li1(g)+Ni1(g)=1].

Furtherconstraints were introduced such that the sum of the Li and Ni occupancies over the two sites was constrained tobe that of the value corresponding to the composition [Li1(g)+Li2(g)=1.2] and [Ni1(g)+Ni2(g)=0.16],
respectively. Figure 2 shows the cycle dependence of lattice parameters for Li1.20-yMn0.55Ni0.16Co0.09O2. We
confirmed that our refined structural model was good fitting with relative low R values for all the samples andclarified that both lattice parameters a and c increased with cycling.

12. 実験方法及び結果（つづき） Experimental method and results (continued)

Intensity (Arb.Unit)

Li1.20-yMn0.55Ni0.16Co0.09O2

After2cycle

After
1 cyclePristine
2.6

2.4

2.2

2.0

1.8

1.6

1.4

1.2

1.0d/Å
Figure 1

ND patterns for Li1.20-yMn0.55Ni0.16Co0.09O2

2.87
14.50
14.45

2.86

14.40
2.85
14.35
14.30

2.84

Lattice paramerters c / ÅLattice parameters a / Å: a-axis: c-axis

14.25
2.83
Pristine

12CyclesFigure 2Cycle dependence of lattice parameters forLi1.20-yMn0.55Ni0.16Co0.09O2

Reference[1]

H. Kobayashi, H. Sakaebe, H. Kageyama, K. Tatsumi, Y. Arachi, T. Kamiyama, J. Mater. Chem., 13(2003) 590-595.
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