| 학회 |
한국화학공학회 |
| 학술대회 |
2017년 가을 (10/25 ~ 10/27, 대전컨벤션센터) |
| 권호 |
23권 2호, p.2419 |
| 발표분야 |
[특별 심포지엄]에너지 저장 및 변환소재 심포지엄(재료부문위원회) |
| 제목 |
리튬이온전지 양극물질 LiNi0.5Mn1.5O4 스피넬의 구조적 안정성 |
| 초록 |
Mixed metal spinel oxides LiNi0.5Mn1.5O4 with two different crystal structures were synthesized by calcining the same bicarbonate precursor at two temperatures 700 and 800 oC. The material obtained at 800 oC showed a much superior stability to the other at 700 oC in electrochemical charge-discharge cycles. The presence of Mn(III) in this material was confirmed by voltammetry and in situ x-ray absorption spectroscopy. The structures and cyclic stability of the both materials were also examined by in situ XRD. The result indicated that the structure of the spinel formed at 700 oC is consistent with the P4332 symmetry and is converted to the Fd-3m structure at 800 oC. It is suggested that the better structural stability of the Fd-3m material originates from the homogeneity of octahedral sites. Such site homogeneity allows random distribution of Mn(III) and Ni(II) on octahedral sites during the calcination and this random exchange of Mn(III) and Ni(II) can delocalize the lattice stress imposed by the large Ni-O distance changes upon electrochemical oxidation of Ni(II) to Ni(IV) at 4.7 V. |
| 저자 |
배인태1, Jennifer Nelson2
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| 소속 |
1Department of Energy Science, 2Sungkyunkwan Univ. / Electrochemical Energy Science LLC |
| 키워드 |
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| E-Mail |
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| VOD |
VOD 보기 |
| 원문파일 |
초록 보기 |
