• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.29-32
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• 2008

The cell performance of direct formic acid fuel cell (DFAFC) having catalysts coated by electrospray was analyzed. Pd catalyst was used for the anode electrode and Pd catalyst loading amount and formic acid feed rate dependances of fuel cell performance were evaluated. When loading amount of Pd is in between 3mg/$cm^2$ and 7mg/$cm^2$ and formic acid feed rate is 5ml/min., 3mg/$cm^2$ sample showed better potential at 129 mA/$cm^2$ and power density due to difference in mass transfer limitation. However, when the feed rate is greater than 10ml/min., the opposite tendency was observed between 3mg/$cm^2$ and 7mg/$cm^2$ samples. The result was attributed to improvement in electrochemical reaction of the Pd. Based on the above results, In DFAFC including Pd catalyst that was coated by electrospray, 0.537V as the maximum potential at 129 mA/$cm^2$ was attained.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.514-523
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• 2021

This study investigated the effect of anode fuel composition on the performance of direct borohydride/hydrogen peroxide fuel cells (DBHPFCs). The effect of sodium borohydride (NaBH₄) and sodium hydroxide (NaOH) concentrations on fuel cell performance was determined through fuel cell tests. Fuel cell performance increased with an increase in the NaBH₄ concentration, whereas it decreased with an increase in the NaOH concentration. The anode fuel composition was selected as 10 wt% NaBH₄+10 wt% NaOH+80 wt% H₂O based on the fuel viscosity, electrochemical reaction rate, and decomposition reaction rate. DBHPFCs were also tested to analyze the effect of operating temperature and operation time on fuel cell performance. The present results can be used as a reference basis to determine operating conditions of DBHPFCs.

• 한국수소및신에너지학회논문집
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• 제25권3호
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• pp.311-318
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• 2014

Performance degradation of a battery in 20 kWh energy storage system (ESS) under various operating conditions was studied. And energy saving of the ESS was also monitored by connecting with 20 kW photovoltaic (PV). PV-connected ESS saved 5~7% of energy consumption in 2013 compared to that without such system in 2012. As charge-discharge cycle increased, capacity decreased and the performance degradation was glaringly obvious after 40 cycles. And as charge and discharge rate increased, the performance degradation was more serious. After 50 charge-discharge cycles, a lot of degraded product was deposited on the surface of anode and cathode electrodes, and the cathode side was more contaminated. Therefore, in order to maintain the cell performance, it was more important to protect the degradation of the cathode side.

• 대한기계학회논문집B
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• 제36권4호
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• pp.439-447
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• 2012

출력 규모가 다른 세가지 상용 가스터빈들을 바탕으로 고체산화물 연료전지/가스터빈 하이브리드 시스템을 구성하고 성능을 비교하였다. 각 가스터빈을 사용할 때 연료전지와 가스터빈의 출력 비중 및 효율을 비교, 분석하였고 연료전지 설계온도를 변화시키면서 출력 비중의 변화와 시스템 효율 변화를 분석하였다. 수십 kW 급 소형 가스터빈을 사용한 하이브리드 시스템에서는 연료전지 온도가 변하여도 효율은 거의 변화가 없었지만 MW 급 및 수백 MW 급 등 중,대형 가스터빈을 사용하는 경우에는 연료 전지 작동온도가 높아질수록 시스템 효율이 높아짐을 확인하였다. 또한 연료전지로 공급되는 공기량을 조절하여 연료전지 출력 비중을 변화시키는 것에 대해서도 해석하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.21-24
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• 2008

Proton Exchange Membrane Fuel Cell (PEMFC) is an attractive candidate for residential power generator due to fast start-up and stop, high efficiency, low emission, and high power density. In this study, we employ short module stack to understand the performance of the unit cell of the stack in terms of operating temperatures. To simulate the practical fuel cell stack of residential power generator, the structure and active area of the short module stack is kept the same as that of the practical fuel cell. The results shows that the electric potential of short module stack is different from the number of cells times the potential of unit cell because of cell-to-cell variation.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.286-288
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• 2007

The research and development for the solid oxide fuel cell have been promoted rapidly and extensively in recent years, because of their high efficiency and future potential. Therefore this paper describes the manufacturing method and characteristics of anode electrode for solid oxide fuel cell, by the way, Ni-YSZ materials are used as anode of solid oxide fuel cell widely. In order to reduce production costs, we have fabricated single solid oxide fuel cell by doctor blade and screen printing method. Disk-type planar solid oxide fuel cell with an effective electrode area of about $7cm^2$ were fabricated and run for 500 h to investigate cell performance. The current density at a voltage of 0.7 V was $850mA/cm^2$.

• 한국가시화정보학회지
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• 제20권3호
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• pp.117-127
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• 2022

The present study has investigated the performance of hydrogen gas generators for inhalation purposes based on polyelectrolyte membrane water electrolysis (PEMWE). The system applied two watering methods. One is pumped water (pumping system) and the other is gravity-fed water without a pump (non-pumping system). The cell efficiencies were compared by measuring the cell voltage and temperature in the hydrogen gas generator, respectively. The results show that the cell voltage and temperature increase with the cell current. The cell temperature is lower in the pumping system than that in the non-pumping system at a given cell current. Even though the amount of hydrogen production is the same regardless of the pumping system, the cell efficiency of the hydrogen gas generator in the non-pumping system is better than that in the pumping system.

• 한국정보통신학회논문지
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• 제17권9호
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• pp.2191-2198
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• 2013

본 논문에서는 실내 위치 인식을 고려한 RFID 기반 셀 구성 방안을 제안하였다. RFID 셀 구성을 위한 4개의 목적함수 설계 및 시뮬레이션 기반 성능 평가뿐만 아니라 RFID 리더를 실내 공간에 실제 배치하여 제안한 기법의 성능평가를 수행하였다. 성능 평가는 RFID 셀 구성에 필요한 최소 RFID 리더 수, 위치 인식이 가능한 최대 셀 영역, 셀 영역 간의 최소 중첩, 그리고 셀 영역의 최대 위치 인식 정확도 측면에서 수행되었다.

• 한국세라믹학회지
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• 제44권12호
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• pp.720-726
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• 2007

Current collectors of SOFC play a significant role on the performance of power generation. In this study a single cell stacked SOFC was assembled using Ag-mesh as a cathode current collector, and evaluated its performance. No gas leakages of the single cell stack occurred in the tests of gas detection and OCV measurement. The OCV and initial power of the stack were 1.09V and $0.45W/cm^2$, respectively, under the flow rates of air at 2,500 cc/min and $H_2$ at 1,000 cc/min at the test temperature of $750^{\circ}C$. A degradation rate of 44.0% was measured during the prolonged time of 307 h. The relatively low durability of the tested single cell stack was found to be the evaporation of Ag-mesh at the current corrector.

• Korean Chemical Engineering Research
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• 제49권6호
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• pp.775-780
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• 2011

50 $cm^2$의 활성면적을 가진 셀을 이용하여 5-셀 DMFC 스택을 제작하고 4 A의 부하로 4,000 시간 운전한 후 성능감소 및 성능 감소 원인을 분석하였다. 4,000 시간 운전 후 10 A에서 스택의 전력 밀도가 28.7% 감소하였으며 다섯개의 셀 중 두 개는 거의 성능저하가 일어나지 않았고 두 개는 약 40%의 성능 저하, 한 개는 약 60%의 성능 저하를 보였으며 각 셀별 성능저하의 정도의 차이는 스택 내에서의 위치와 상관관계가 없었다. 스택 내의 다섯 셀 중 가장 성능감소가 심하였던 셀의 경우 연료극 촉매층의 Pt 입자 크기가 증가하였으며 연료가 들어가는 쪽의 Pt 입자의 크기 증가가 더 심하였다. 그러나 4,000 시간 장기운전 후 공기극 촉매층에서는 Pt 입자 크기의 변화는 거의 없었다. 스택 내의 모든 셀에서 4,000 시간 운전 후 연료극 촉매에서 공기극 촉매로의 루테늄의 크로스오버가 SEM-EDX로 관찰되었으며 특히 성능감소가 심하였던 셀의 경우 공기극 촉매층에서 Ru/Pt의 비율이 가장 컸다.