• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.627-628
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• 2005

In recent years, the rapid growth of portable electronic device market requires higher density characteristics of batteries. The speed at which portability and mobility is advancing hinges much on the battery. What is important is this energy source that engineers design handled devices around the battery, rather than the other way around. Much improvement has been made in reducing the power consumption of portable devices. Currently, the most popular secondary battery is Li-ion battery. Li-ion has won the limelight and become the most prominent battery. This paper reviews the prospect and future of the Li-ion battery.

• Journal of Magnetics
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• 제18권3호
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• pp.221-224
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• 2013

Electron paramagnetic resonance (EPR) spectra of $Mn^{2+}$ impurity ion in Stoichiometric $LiNbO_3$ single crystal (SLN) was investigated with an X-band EPR spectrometer in the temperature range of 3 K~296 K. The intensity of EPR spectrum of $Mn^{2+}$ ion was increased to 20 K and decreased again below 20 K as the temperature decreases. The zero-field splitting parameter D decreased as the temperature increases. It was suggested that $Mn^{2+}$ ion substitute for $Nb^{5+}$ ion instead of $Li^+$ ion. No changes for hyperfine interaction of $Mn^{2+}$ ion was obtained in the temperature range of 3 K~296 K.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1054-1057
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• 1995

The pollution-free secondary Li ion battery has been developed recently. However due to short history of Li ion battery, the standards for characterized assessments and standardized testing methods have not been prepared and established yet. Also, the researches have not been done systematically regarding the operating methods of these new type of batteries. Such limited knowledge of new batteries emphasizes the importance of development of characterized assessment and the operating methods.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2004년도 춘계총회 및 학술발표회
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• pp.20-20
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• 2004

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.109-109
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• 2000

• Journal of Power Electronics
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• 제17권2호
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• pp.501-513
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• 2017

The fundamental small-signal modeling of lithium-ion (Li-ion) batteries and a parameter evaluation approach are investigated in this study to describe the dynamic behaviors of small signals accurately. The main contributions of the study are as follows. 1) The operational principle of the small signals of Li-ion batteries is revealed to prove that the sinusoidal voltage response of a Li-ion battery is a result of a sinusoidal current stimulation of an AC small signals. 2) Three small-signal measurement conditions, namely stability, causality, and linearity, are proved mathematically proven to ensure the validity of the frequency response of the experimental data. 3) Based on the internal structure and electrochemical operational mechanism of the battery, an AC small-signal model is established to depict its dynamic behaviors. 4) A classical least-squares curve fitting for experimental data, referred as Levy's method, are introduced and developed to identify small-signal model parameters. Experimental and simulation results show that the measured frequency response data fit well within reading accuracy of the simulated results; moreover, the small-signal parameters identified by Levy's method are remarkably close to the measured parameters. Although the fundamental and parameter evaluation approaches are discussed for Li-ion batteries, they are expected to be applicable for other batteries.

• 폴리머
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• 제27권4호
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• pp.385-391
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• 2003

본 연구에서는 에틸렌 옥사이드의 반복 단위 길이 (n＝3, 7.3, 11.8, 그리고 16.3)가 다른 리튬 p-［메톡시 올리고(에틸렌옥시)］벤젠설폰산염 (LiEOnBS)을 합성하였다. 이 전해질 염을 이용하여 고분자 전해질을 제조하였으며, 에틸렌 옥사이드의 반복 단위 길이 및 농도에 따른 이온 전도도 그리고 리튬 이온의 운반율에 대해 조사하였다. 고분자 전해질의 이온 전도도는 3$0^{\circ}C$에서 4.89$\times$$10^{-4}$ S/cm (LiEO7.3BS, 0.5 M)로 최고 이온 전도도를 보였다. Dc분극과 ac 임피던스를 혼합하여 측정한 고분자 전해질의 리튬 이온의 운반율은 0.75~0.92 이였으며, 농도가 증가할수록 리튬 이온 운반율은 감소하였다. LiEO7.3BS의 전해질 염을 0.1 M로 사용한 고분자 전해질인 경우 0.92로 최고의 리튬 이온 운반율을 보였다. 이로부터 벤젠설포네이트에 치환된 에틸렌 옥사이드의 반복 단위가 3이상만 되어도 높은 리튬 이온 운반율을 가지는 단일 이온 전해질 특성을 보임을 알 수 있었다.

• 한국세라믹학회지
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• 제33권3호
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• pp.293-298
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• 1996

Room temperature Li+ ion conductivities of Li3xLa(2/3-x)TiO3 system with x=0.117~0.317 were measured by complex impedance method. ICP, SEM and XRD analysis were conducted to study the main factor which influence the Li+ ion conductivity. Li+ ion conductivity seems to have a close relationship with the crystal structure of primitive cell increase as the primitive cell as close to cubic.

• Journal of Magnetics
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• 제6권3호
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• pp.77-79
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• 2001

The semi-empirical superposition model has been applied to calculate the zero field splitting parameters of $Mn^{2+}$ion in $LiTaO_3$ single crystal, assuming that $Mn^{2+}$ion occupies one of two possible sites: $Li^{l+} \;or\; Ta^{5+}$ site, respectively. The 2nd-order axial zero field splitting parameters are $958\times10^{-4}cm^{-1}\; at\; Li^{1+}$ site and $193\times 10^{-4}cm^{-1} \;at\; Ta^{5+}$ site for $Mn^{2+}$ions. The 4th-order zero field splitting parameters at $Li^{l+} \;and\; Ta^{5+}$ sites are also determined. These calculated zero field splitting parameters are very important to determine the substitutional sites of doped impurity ions in $LiTaO_3$ crystal.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.143-146
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• 1998

The $LiCoO_2$ powder was synthesized at >$700^{\circ}C$, >$850^{\circ}C$ by solution route. In this paper, we investigated X-ray diffraction, and charge-discharge performance for $LiCoO_2$/Li and $LiCoO_2$/MPCF cell. The $LiCoO_2$/Li ceSl exhibited a high avmge discharge potential of 38-3% and a good cycle life performance at 5(hnA/g during chargedischarge cycling between 43-3.0V. And, the $LiCoO_2$MPCF cell showed a high average discharge voltage of 3.6-3.W and a excellent cycle life prfomam during chargedischarge cycling b&wm 4 2-2.W. As a result, the $LiCoO_2$ powdm syd-eizd by solution route is a good cathode material for lithium ion secondary battery.