• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.553-554
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• 2006

This paper presents the effects of different operating parameters on the performance of a proton exchange membrane (PEM) fuel cell by a three-dimensional computational fluid dynamics (CFD) model. The effects of different operating parameters on the performance of PEM fuel cell studied using pure hydrogen on the anode side and air on the cathode side. The various parameters are temperatures, pressures, humidification of the gas steams and various combinations of these parameters. In addition, geometrical and material parameters such as the gas diffusion layer (GDL) thickness and porosity as well as the ratio between the channel width and the land area were investigated.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.154-157
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• 2009

Fuel cell is spotlighted as next energy source of future. The fuel of vehicle will be changed from fossil fuel such as gasoline, diesel to hydrogen. Polymer electrolyte membrane fuel cell(PEMFC) will be used to fuel cell vehicle because of its suitability. PEMFCs need oxygen for cathode. Because PEMFCs in vehicle use air for oxygen, air pollutant will be effect to performance of PEMFC. In this study, we examine a type of filter and pollutant gas how can be effect to performance of fuel cell electric vehicle.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.109-112
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• 1996

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for all-stolid-state lithium battery. We investigated conductivity, electrochemical properites and impedence spectroscopy of poly(ethylene oxide)[PEO]/poly(vinylidene fluoride)[PVOF] blend electrolytes and charge/discharge cycling of LiCoO$_2$/SPE/Li cell. By adding PVDF and plasticizer to PEO-LICIO$_4$electrolyte, its condustivity was higher than that of PEO-LiCIO$_4$electrolyte. Also PEO$_4$PVDF$_4$LiClO$_4$PC$_{5}$EC$_{5}$ remains stable up to 4.4V vs Li/Li. The discharge capacity of the LiCoO$_2$composite cathode was 92mAh/g based on LiCoO$_2$.EX>.

• ETRI Journal
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• v.18 no.3
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• pp.195-206
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• 1996

Molecular conformations of stereoregular poly(methyl methacrylate) (PMMA) monolayers have been investigated by scanning probe microscopes. Isotactic and syndiotactic PMMAs were found to have right and left hand helical structures, respectively. On the contrary atactic PMMA showed rather random arrangement of the chains. It has been demonstrated that the PMMA Langmuir-Blodgett (LB) films can be utilized to form nanoscale patterns down to 50 nm and to forma geodesic lens. It has also been manifested that the quantum efficiency of a polymer electroluminescent device can be significantly enhanced by inserting the PMMA LB films between the emitting layer and the cathode. All the applications utilize the unique characteristics of the LB films to form thin and uniform films in the molecular level.

• Journal of the Korean Electrochemical Society
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• v.6 no.3
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• pp.174-177
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• 2003

Electric double-layer capacitors based on charge storage at the interface between a high surface area activated carbon electrode and an electrolyte solution are characterized by their long cycle-life and high power density in comparison with batteries. However, energy density of electric double-layer capacitors obtained at present is about 6 Wh/kg at a power density of 500W/kg which is smaller as compared with that of batteries and limits the wide spread use of the capacitors. Therefore, a new capacitor that shows larger energy density than that of electric double-layer capacitors is proposed. The new capacitor is the hybrid capacitor consisting of activated carbon cathode, carbonaceous anode and an organic electrolyte. Maximum voltage applicable to the cell is over 4.2V that is larger than that of the electric double-layer capacitor. As a result, discharged energy density on the basis of stacked volume of electrode, current collector and separator is more than 18Wh/l at a power density of 500W/l.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.362-365
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• 1999

The electrochemical properties of flyash obtained from combustion of fuel in fossil power plants and their performance as anode material of secondary battery have been investigated Various flysh pellets molded at various molding pressure have been used as anode lithium secondary battery. The best Performance was achieved when flyash pellet molded at pressure of 400kgf/$\textrm{cm}^2$ is utilized, that is, charge capacity of 300kgf/$\textrm{cm}^2$ and Coulombic efficiency of larger than 95% have been achieved. In addition, this battery exhibited good cycling performance. Considering these results, we predicted that utilization of the flyash as anode material and polyaniline conducting polymer as cathode material in a secondary will show capacity of 300mAh/g and Coulombic efficiency of higher than 95%.

• Transactions on Electrical and Electronic Materials
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• v.2 no.4
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• pp.7-10
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• 2001

A new possibility of our atmospheric cold plasma torch has been examined on the surface treatment of an air-exposed vulcanized rubber compound. The plasma treatment effect was evaluated by the bondability with another rubber compound using a polyurethane adhesive. The adhesion property was improved by the treatment with plasma containing oxygen radicals. The oxygen radical generation from the plasma was verified and its efficiency was found to be dependent on the cathode material.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.461-462
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• 2017

가장 대표적인 연료전지인 고분자 전해질 연료전지(PEMFC; polymer electrolyte membrane fuel cell)은 두 개의 전극으로 이루어지며, 각 전극(electrode)에 공급되는 수소(anode)와 공기(cathode)의 원활한 반응을 위해 촉매(catalyst)로서 백금(Pt)을 사용한다. 이 때, 촉매의 실험 조건에 따라 연료전지 두 전극의 반응이 달라지므로 촉매의 가변성 즉, 가변적인 전극 조건에 따른 전기화학적 특성이 면밀히 분석되어야 한다. 그러므로, 본 논문에서는 촉매의 변화에 기인한 가변적인 전극 특성에 따른 연료전지의 전기화학적 특성 분석을 실시하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.11
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• pp.922-927
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• 2001

Single-layer green ELs was fabricated with using molecularly-dispersed Bu-PBD into poly-N-vinylcarbazole(PVK) which has low operating voltage and high quantum efficiency. A EL cell structure of glass substrate/indium-tin-oxide/PVK:Bu-PBD:C6(∼ 100nm)/Ca(20nm)/Al(20nm) was employed with variable doping concentration. The keys to obtain high quantum efficiency was excellent film forming capability of molecularly dispersed into PVK and appropriate combination of cathode for avoiding exciplex. We obtained the turn-on voltage of 4.2V and quantum efficiency of 0.52% at 0.lmol% of C6 concentration which has been improved about a factor of 50 in comparison with the undoped cell. The PL peak wavelengths wouldn\`t be turned by changing the concentration of the C6 dopant. Green EL emission peak and FWHM were 520nm and 70nm respectively. PL emission peak was obtained at 495nm.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.643-647
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• 2003

Direct methanol fuel cells (DMFC) employing proton exchange polymer electrolyte have recently gained considerable interest because of their attractiveness as the power source for electronic devices or vehicular applications. However, it suffers from the fuel crossover and its impact on cathode operation and the consequent penalty in system energy efficiency. Efforts to circumvent the methanol crossover in DMFC have been made basically along three different strategies.(Omitted)