• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.2
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• pp.133-138
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• 2024

Lithium-ion batteries are used in many fields due to their high energy density, fast charging conditions, and long cycle life. However, overcharging, over-discharging, physical damage, and use of lithium-ion batteries at high temperatures can reduce battery life and cause damage to people due to fire or explosion due to damage to the protection circuit. In order to reduce the risk of these batteries and improve battery performance, the characteristics of the charging and discharging process must be analyzed and understood. Therefore, in this paper, we analyze the charging and discharging characteristics of lithium-ion batteries using a battery charger and discharger and simulator to reduce the risk of loss of life due to overcharge and overdischarge, as well as casualties from fire and explosion due to damage to the protection circuit.

• Journal of the Korean Electrochemical Society
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• v.2 no.1
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• pp.1-4
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• 1999

A lithium ion battery with polymer electrolyte is expected as a safe and long cycle life battery. This paper reports primarily the recent development results of a solid polymer electrolyte, which is a key factor of the secondary battery system, that has been obtained during the process of the development of a polymer type lithium battery. As a successful result of the solid polymer electrolyte. The ionic conductivity of the solid polymer electrolyte, which is composed of polyacrylonitrile and $LiClO_4\;with\; Al_2O_3$ dissolved as the supporting electrolyte, has been confirmed to be $2.3\times10^{-4} S/cm$ at room temperature.

• Clean Technology
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• v.18 no.3
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• pp.320-324
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• 2012

In the present study, the discharge characteristics of a lithium-ion battery was evaluated to calculate the rate of heat generation under various discharge rates by mathematical modeling. The modeling and simulation of a pseudo-two dimensional ionic transport system for governing Butler-Volmer equation were carried out by using FEMLAB as a PDE (partial differential equation) solver, where the discharge rate was changed from 5 $A/m^2$ to 25 $A/m^2$. The computational results showed that the concentration of consumed solid-phase lithium at the surface of electrode was increased with increasing discharge rates. While the resulting diffusion limitation occurred shortly, it increased the rate of heat generation even more rapidly for the internal voltage to approach the cutoff voltage of the lithium-ion battery.

• Prospectives of Industrial Chemistry
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• v.23 no.1
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• pp.3-17
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• 2020

리튬이온전지(LIB)는 기존의 다른 이차전지와 다른 확실한 몇 가지 장점이 있다. 높은 작동 전압과 높은 에너지 밀도, 긴 수명, 그리고 낮은 자체 방전 속도이다. 이러한 장점으로 모바일 제품에서부터 전기 자동차(battery electric vehicle, BEV), 최근에는 전기저장장치(energy storage system, ESS)까지 다양한 분야에서 사용되고 있다. 하지만 사용 범위가 증가함에 따라 높은 안정성을 가지며 더 큰 에너지 용량을 나타내는 리튬이온전지에 대한 요구가 점점 더 커지게 되었다. 리튬이온전지의 용량 증가는 전지의 설계보다는 양극 및 음극 재료, 분리막 및 전해질과 같은 주요 전지 재료의 기술적 진보에 달려 있다. 주요 전지 소재 중에 전지의 성능에 가장 큰 영향을 미치는 것은 전지 반응에 의한 과전압과 가격이 가장 비싼 양극이다. 본 기획 특집에서는 리튬이차전지의 성능에 가장 큰 영향을 미치는 양극 물질의 종류와 향후 연구동향에 대해서 소개하고자 한다. 양극 물질의 발전 방향, 안정성과 용량 증대를 위해서 최근 연구되고 있는 방향에 대해서 자세하게 소개한다.

• Journal of the Korean Chemical Society
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• v.45 no.3
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• pp.219-222
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• 2001

Separation of lithium isotopes was investigated by chemical ion exchange with a hydrous manganese(IV) oxide ion exchanger using an elution chromatography. The capacity of manganese(IV) oxide ion exchanger was 0.5 meq/g. The heavier lithium isotope was enriched in the solution phase, while the lighter isotope was enriched in the ion exchanger phase. The separation factor was determined according to the method of Glueckauf from the elution curve and isotopic assays. The separation factor of $^6Li^+$-$^7Li^+$ isotope pair fractionation was 1.018.

• Fire Science and Engineering
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• v.33 no.1
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• pp.23-29
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• 2019

Rechargeable battery such as lithium-ion battery has been noticed as a kinds of the energy storage system in the recent energy utilization and widely used actually in various small electronic equipment and electric vehicles. However, many thermal runaway caused battery accidents occurred recently, which still is obstacle for advanced application of lithium ion battery. One of the main differences to general fires is the existence of ionized electrolyte with electron during combustion. Therefore, we simply simulated the ion addition effects of battery fires by introducing an ionized fuel in jet diffusion flames. When the ionized methane through a corona discharge was used as fuel, the overall flame stability and shape such as flame length showed no significant difference from normal methane flame, but NOx and CO emissions measured at the post flame region decreased. The ion addition effect of methane oxidation was also numerically simulated with the modeling of hydrogen addition in the mixture. It was confirmed that the hydrogen addition at a fixed temperature had a similar effects on ionization of methane and hence could be modeled successfully.

• Membrane Journal
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• v.14 no.4
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• pp.263-274
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• 2004

The polymeric membrane, a component of battery devices such as Li-ion battery (LIB) and Li-polymer battery (LPB), is a typical material in which the carrier mobility dominates the battery performance. In this paper, the state-of-the-art of membranes for secondary battery is described in terms of membrane properties. Several prerequisites, which are related to stability of battery devices, are discussed to design and prepare suitable polymeric membranes. In addition, physical requirements of membranes and their measurement methods are described to develop applicable polymeric membranes in membrane preparation processes.

• Journal of the Korean Vacuum Society
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• v.16 no.3
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• pp.227-230
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• 2007

In the Li ion battery fabrication process, an aging step has treated as a miner step because there is not so much data to define the relationship between the phenomena generated in aging process and the battery performances. However, the OCV(open circuit voltage) change in the aging process is shown by the electrochemical absorption of the electrolyte component to the both electrodes(anode or cathode) and the absorbed layer to the electrode affects to form the solid electrolyte interface(SEI) layer during the first charge process. In this report, the adsorbed materials are designed deliberately and are cleared to affect to the SEI layer formation.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.195-204
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• 2023

The drone's battery system uses lithium-ion or lithium-polymer batteries, and it is known that the cause of fire during the disposal process after using the drone is combustible gas from the battery being discarded. Most of the batteries in the disposal process generated oxygen, but a small amount of flammable gas was also generated, and a large amount of chlorine ions and sulfates were also detected in the equipment used for treatment. If a system that detects this early is configured, it will be possible to reduce the risk of accidents caused by discarded batteries.

• Membrane Journal
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• v.33 no.1
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• pp.13-22
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• 2023

Despite high capacity of lithium metal anode, its uncontrollable dendrite growth results in the poor electrochemical (EC) performance (low Coulomb efficiency and limited cycle stability) and unsafe operation. In this study, we demonstrated a lithium metal anode protected with BaTiO₃/PVDF based piezoelectric layer to enhance its EC performance by utilizing the locally polarized lithium metal after volume expansions. As-formed lithium metal electrode deposited with BTO@PVDF layer exhibited an enhanced Coulombic efficiency (> 98% for 100 cycles) and facilitated lithium ion diffusions (lithium diffusion coefficient: D_Li+), revealing the effectiveness of piezoelectric layer deposited lithium metal electrode approach.