• Journal of the Korean Society of Visualization
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• v.21 no.3
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• pp.49-56
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• 2023

The Polymer electrolyte membrane fuel cell (PEMFC) operates at ambient temperature as a low-temperature fuel cell. During its operation, voltage losses arise due to factors such as operating conditions and material properties, effecting its performance. Computational simulations of fuel cells can be categorized into 1D simulation and CFD, chosen based on their specific application purposes. In this study, we carried out an analysis validation using 1D geometry and compared its performance with the results from 2D geometry analysis. CFD allows for the representation of pressure, velocity distribution, and fuel mass fraction according to the geometry, enabling the analysis of current density. However, the 1D simulation, simplifying governing equations to reduce time cost, failed to accurately account for fuel distribution and changes in fuel concentration due to fuel cell operations. As a result, it showed unrealistic results in the cell voltage region dominated by concentration loss compared to CFD.

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.83-86
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• 2005

• Membrane Journal
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• v.20 no.1
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• pp.40-46
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• 2010

In this study, we manufactured the membrane using the polyethersulfone (PES) of fiber by using the electrospinning method. The polymer electrolyte membrane for fuel cells was manufactured by impregnating Nafion solution to the porous PES membrane. We confirmed that electrospun PES membrane has higher thermal stability than Nafion 212 membrane by thermogravimetric analysis. Impregnated Nafion in the pores of the electrospun PES membrane was characterized by scanning electron microscopy. The AC impedance data shows the hydrogen ionic conductivity of $10^{-2}$ S/cm below $100^{\circ}C$. Nafion impregnated PES membrane shows the maximum performance at $90^{\circ}C$ showing current density of 389 mA/$cm^2$ at 0.6 V, while Nafion 212 membrane shows maximum at $75^{\circ}C$.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.330-334
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• 2005

고분자 전해질막 연료전지는 운전시 정상적인 성능을 발현하기 이해서 전지 본체 조립 후 초기 활성화 운전이 필요하다. 이러한 활성화 운전을 통해 전해질 사이의 수소이온이동 통로, 반응가스가 반응할 수 있는 촉매까지의 이동 통로, 촉매층내의 전기적 연속성을 확보함으로 연료전지는 최적의 성능을 나타낼 수 있다. 본 연구를 통해 연료전지 활성화에 영향을 미치는 요인을 찾았고, 이를 통해 효과적이고 빠른 활성화 절차에 관한 연구를 수행하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.169-171
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• 2007

A breaking layer was introduced to conventional decal transfer method in membrane electrolyte assembly fabrication for high catalyst transfer ratio. In this study, the modified decal transfer method with high catalyst transfer ratio was introduced and its performance is studied. The structural features of electrodes made by decal method were investigated using scanning electron microscopy and current-voltage polarization measurement.

• New & Renewable Energy
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• v.1 no.2 s.2
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• pp.34-40
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• 2005

고분자 전해질막 연료전지는 운전시 정상적인 성능을 발현하기 위해서 전지 본체 조립 후 초기 활성화 운전이 필요하다. 이러한 활성화 운전을 통해 전해질 사이의 수소이온이동 통로, 반응가스가 반응할 수 있는 촉매까지의 이동 통로, 촉매층내의 전기적 연속성을 확보함으로 연료전지는 최적의 성능을 나타낼 수 있다. 본 연구를 통해 연료전지 활성화에 영향을 미치는 요인을 찾았고, 이를 통해 효과적이고 빠른 활성화 절차에 관한 연구를 수행하였다.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.2
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• pp.127-135
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• 2015

High-Temperautre Polymer Electrolyte Membrane Fuel Cell (HT-PEMFC) with phosphoric acid-doped polybenzimidazole (PBI) membrane has high power density because of high operating temperature from 100 to $200^{\circ}C$. In fuel cell stack, heat is generated by electrochemical reaction and high operating temperature makes a lot of heat. This heat is caouse of durability and performance decrease about stack. For these reasons, heat management is important in HT-PEMFC. So, we developed HT-PEMFC model and study heat flow in HT-PEMFC stack. In this study, we placed coolant plate number per cell number ratio as variable and analysed heat flow distribution in stack.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.1
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• pp.59-64
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• 2004

The performance of fuel cell electrode depends on the characteristics of the catalyst support material. This paper deals with the use of CNF(carbon nanofibre) and CNT(carbon nanotube) as platinum catalyst support. The CNF and CNT were synthesized with catalyst treated by mechanochemical process and were prepared by chemical vapor deposition (CVD) method. The platinum supported on CNF and CNT for polymer electrolyte membrane fuel cell (PEMFC) application. In result, the best I-V characteristic was verified by the prepared MEA(membrane electrode assembly) from twisted CNF that had a diameter of 65 nm.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.107-109
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• 2006

This study focuses on a determination of amount of Pt in the Pt/C for catalysts of polymer electrolyte membrane fuel cells (PEMFC). PEMFC offer low weight and high power density and being considered for automotive and stationary power applications. The PEMFC performance is influenced by several factors, including catalysts and structure of electrode and membrane type. Catalyst of electrode is important factor for PEMFC. One of the obstacles prevent ing polymer electrolyte membrane fuel cells from commercialization is the high cost of noble metals to be used as catalyst, such as platinum To effectively use these metals, they have to be will dispersed to small particles on conductive carbon supports. The optimal amount of Pt in Pt/C for cathode catalyst was investigated by using polarization curves in single cell with $H_2/O_2$ operation.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1030-1035
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• 1998

The porous alumina membrane was prepared from aluminum metal(99.8%) by anodic oxidation using DC power supply of constant current mode in an aqueous solution of sulfuric acid. To prevent the chemical dissolution of alumina membrane, $Al_2(SO_4)_3$, $AlPO_4$ and $Al(NO_3)_3$ which could be considered to supply $Al^{3+}$ ions were added to electrolyte solution at a reaction temperature of $20^{\circ}C$ and cumulative charge of $150C/cm^2$. Effects of these additives on the formation of porous alumina membrane were evaluated under various electrolyte concentration(5~20 wt%) and current densities($10{\sim}50mA/cm^2$). The membrane surfaces which were prepared in electrolyte solution with all the additives except $Al_2(SO_4)_3$ were damaged. However, when $Al_2(SO_4)_3$ was added to the $H_2SO_4$ solution, an uniform surface of porous alumina was obtained. Also, it was shown that the pore size of membrane was nearly independent on the quantity of $Al_2(SO_4)_3$ added at same electrolyte concentration and current density.