• E2M - 전기 전자와 첨단 소재
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• 제14권12호
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• pp.7-10
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• 2001

Orthorhombic type LiCo$_{x}$Mn$_{1-x}$ O$_2$(0$\leq$x$\leq$0.14) oxides have been synthesized by hydrothermal treatment of (Co$_{x}$Mn$_{1-x}$ )$_3$O$_4$precursors and LiOH aqueous solution at 17$0^{\circ}C$. As-synthesized powders showed well-ordered $\beta$-MaMnO$_2$structures, and the products were single crystalline particle oxides from TEM observations. The particle size decreased with increasing the amount of Co substituent. Much more improved capacity upon 100 cyclings was clearly seen in orthorhombic LiCo$_{0.1}$Mn$_{0.9}$O$_2$, comparing to orthorhombic LiMnO$_2$./TEX>.EX>.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 춘계학술대회 논문집
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• pp.79-84
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• 1993

This paper describes the development of lithium rechargeable cell. $LiCoO_2$ is recently recognized as a suitable cathode active material of a high voltage, high energy lithium rechargeable batteries because $Li^+$ ion can be electrochemically deintercalated/intercalated from/to $Li_xCoO_2$. The transition metal oxide of $LiCoO_2$ was investigated for using as a cathode active material of 4V class Li rechargeable cell. $LiCoO_2$ cathode was prepared by using a active material of 85 wt%, graphite powder of 12 wt% as a conductor and poly-vinylidene fluoride of 3 wt% as a binder. The electrochemical and charge/discharge properties of $LiCoO_2$ were investigated by cyclic voltammetry and galvanostatic charge/discharge. The open circuit voltage of prepared $LiCoO_2$ electrode exhibited approximately. potential range between 3.32V and 3.42V. During the galvanostatic charge/discharge, $LiCoO_2/Li$ cell showed stable cycling behavior at scan rate of 1mV/sec and potential range between 3.6V and 4.2V. Also its coulombic efficiency as function of cycling was 81%~102%. In this study the $LiCoO_2/Li$ cell showed the available discharge capacity of 90.1 mAh/g at current density of $1mA/cm^2$ and cell discharge voltage range between 3.6V~4.2V.

• 한국전기전자재료학회논문지
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• 제11권11호
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• pp.1049-1054
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• 1998

The LiCo$O_2$ powder was synthesized by a solution phase reaction. This shows a high (003) peak intensity and low (104) or (101) peak intensities in X-ray diffraction spectra. The LiCo$O_2$/Li cell shows an initial discharge capacity of 102.9mAh/g and an average discharge potential or 3.877V at a current density of 50mA/g between 3.0~4.2V. The peaks of dQ/dV plot are associated with Li ion intercalation/deintercalation reaction. To evaluate the cycleability of an actual battery system, cylindrical lithium ion cell was manufactured using graphitized MPCF anode and LiCoO$_2$ cathode. After 100th cycle, this cel maintains 80% capacity of 10th cycle value. The LiCoO$_2$/MPCF cell has a high discharge voltage of 3.6~3.7V and a good cycle life performance on cycling between 4.2~2.7V.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.27-28
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• 2009

In this study, we have fabricated the 3 wt% $Li_2CO3$ doped $(Ba,Sr)TiO_3$ thick films on the Ag/Pd printed $Al_2O_3$ substrates for the LTCCs (Low Temperature Co-fired Ceramics) applications. From the X-ray diffraion analysis, 3 wt% $Li_2CO3$ doped BST thick films on the Ag/Pd printed $Al_2O_3$ substrates, which sintered at 900 $^{\circ}C$ have perovskite structure without any pyro phase. The dielectric properties of 3 wt% $Li_2CO3$ doped BST thick films were measured from 1 kHz to 1 MHz. To investigate the electrical properties of 3 wt% $Li_2CO3$ doped BST thick films, we employed the impedance spectroscopy. The complex impedance of 3 wt% $Li_2CO3$ doped BST thick films were measured from 20 Hz to 1 MHz at the various temperatures.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1999년도 춘계 학술발표회 논문집
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• pp.225-228
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• 1999

MCFC의 장수명화를 위해 기존의 Li$_2$CO$_3$-K$_2$CO$_3$계 전해질을 Li$_2$CO$_3$-$Na_2$CO$_3$계 용융탄산염으로 대체함으로써, 전지 수명을 단축시키는 NiO의 용출을 억제하고자하는 연구가 진행중에 있다. 이러한 대체 Li$_2$CO$_3$-$Na_2$CO$_3$ 전해질은 실제 전지에서 사용되고 있는 분리판 재료인 스테인레스강의 안정성에도 기존의 Li$_2$CO$_3$-K$_2$CO$_3$ 혼합염과는 다른 경향을 보이는 것으로 알려져 있다.(중략)

• 자원리싸이클링
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• 제14권6호
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• pp.37-43
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• 2005

페리튬이온전지로부터 회수된 코발트와 리튬 침출액으로부터 화염분부열분해법에 의하여 $LiCoO_{2}$ 나노분말을 제조하였다. 리튬 및 코발트 성분을 함유하는 전극물질은 열처리 및 기계적 처리에 의해 그 농도를 증가 시켰다. 리튬이온전지 양극물질을 질산으로 용해한 다음 침출액중 Li과 Co의 당량비가 1.0 되도록 $LiNO_{3}$로 조절하여 화염분무열분해용 전구체를 제조하었다. 화염분무열분해법에 의해 제조된 $LiCoO_{2}$ 분말의 평균입자크기는 전구체의 몰 농도가 증가하면서 증가되었으며, 화염온도 역시 입자의 크기를 증가시켰다. 변수실험 결과 $11{\~}35nm$ 크기의 결정형 $LiCoO_{2}$ 나노분말을 제조할 수 있었다 또한 나노 $LiCoO_{2}$의 전극재료로서의 가능성을 확인하기 위하여 충방전 특성 평가와 같은 전기화학적 분석을 수행하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.7-10
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• 2001

Orthorhombic type $LiCo_{x}Mn_{1-x}O_{2}$(0 ${\times}$ 0.14) oxides have been synthesized by hydrothermal treatment of $(Co_{x}Mn_{1-x})_{3}O_{4}$ precursors and LiOH aqueous solution at $170^{\circ}C$. As-synthesized powders showed well-ordered ${\beta}-NaMnO_{2}$ structures, and the products were single crystalline particle oxides from TEM observations. The particle size decreased with increasing the amount of Co substituent. Much more improved capacity upon 100 cyclings was clearly seen in orthorhombic $LiCo_{0.1}Mn_{0.9}O_{2}$, comparing to orthorhombic $LiMnO_2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.7-10
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• 2001

Orthorhombic type $LiCo_{x}Mn_{1-x}O_2$ (0 x 0.14) oxides have been synthesized by hydrothermal treatment of ($Co_{x}Mn_{1-x}$)$_3O_4$ precursors and LiOH aqueous solution at $170^{\circ}C$. As-synthesized powders showed well-ordered ${\beta}$-$NaMnO_2$ structures, and the products were single crystalline particle oxides from TEM observations. The particle size decreased with increasing the amount of Co substituent. Much more improved capacity upon 100 cyclings was clearly seen in orthorhombic $LiCo_{0.1}Mn_{0.9}O_2$, comparing to orthorhombic $LiMnO_2$.

• 한국재료학회지
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• 제11권5호
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• pp.339-344
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• 2001

코발트 산화물 박막을 전극으로 하여 Pt/Ti/Si 기판위에 Co$_3$O$_4$/LiPON/Co$_3$O$_4$로 구성된 전고상의 박막형 슈퍼캐패시터를 제작하였다. 각각의 Co$_3$O$_4$박막은 반응성 dc 마그네트론 스퍼터를 이용하여 $O_2$/[Ar+O$_2$] 비를 증가 시키며 성장시켰고, 비정질 LiPON 고체전해질 박막은 순수한 질소분위기 하에서 rf 스퍼터링으로 성장시켰다. 비록 벌크 타입의 슈퍼캐패시터에 비해 낮은 전기용량 (5-25mF/$\textrm{cm}^2$-$\mu\textrm{m}$)을 가졌지만, Co$_3$O$_4$/LiPON/Co$_3$O$_4$ 구조로 제작된 전고상 박막형 슈퍼캐패시터는 벌크 타입과 비슷한 거동을 나타내었다 0-2V의 전압구간, 50$\mu\textrm{A}/\textrm{cm}^2$의 전류밀도에서 약 400사이클 까지 안정한 방전용량을 유지함을 관찰할 수 있었다 이러한 전고상 박막형 슈퍼캐패시터의 전기화학적 특성은 $O_2$/[Ar+O$_2$] 비에 의존하는데, 이러한 의존성을 구조적, 전기적 특성 및 표면특성을 분석하여 설명하였다.

• 한국세라믹학회지
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• 제47권1호
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• pp.61-65
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• 2010

Ultrathin atomic layer deposition (ALD) coatings were found to enhance the performance of lithium-ion batteries (LIBs). Previous studies have demonstrated that $LiCoO_2$ cathode powders coated with metal oxides with thicknesses of $\sim100-1000{\AA}$ grown using wet chemical techniques improved LIB performance. In this study, $LiCoO_2$ powders were coated with conformal $Al_2O_3$ ALD films with thicknesses of only $\sim3-4{\AA}$ established using 2 ALD cycles. The coated $LiCoO_2$ powders exhibited a capacity retention of 89% after 120 charge-discharge cycles in the 3.3~4.5 V (vs. $Li/Li^+$) range. In contrast, the bare $LiCoO_2$ powders displayed only a 45% capacity retention. This dramatic improvement may result from the ultrathin $Al_2O_3$ ALD film acting to minimize Co dissolution or to reduce surface electrolyte reactions.