• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2007년도 추계학술 발표회
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• pp.193-198
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• 2007

KIER has been developing the anode supported flat tubular SOFC stack for the intermediate temperature $(700{\sim}800^{\circ}C)$ operation. for this purpose, we have first fabricated anode supported flat tubular cells by the optimization between the current collecting method and the induction brazing process. After that we designed the compact fuel & air manifold by adopting the simulation technique to uniformly supply fuel & air gas and the unique seal & insulation method to make the more compact stack. For making stack, the prepared anode-supported flat tubular cells with effective electrode area of $90cm^2$ of connected in series with 12 modules, in which one module consists of two cells connected in parallel. The performance of stack in 3 % humidified $H_2$ and air at $800^{\circ}C$ shows maximum power of 507 W. Through these experiments, we obtained basic & advanced technology of the anode-supported flat tubular cell and established the proprietary concept of the anode-supported flat tubular SOFC stack in KIER.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.160-164
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• 1991

The effect of various parameters, such as temperature, current density and operating valtage on the performance of phosphoric acid fuel cell stack was studied by using numerical analysis. The utilization ratio of reaction gas, inlet condition of reaction air and cooling air, inlet condition of cooling air flow latin were changed regularly, The results showed good agreements with the existing results and experimental ones.

• Journal of Advanced Marine Engineering and Technology
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• 제39권7호
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• pp.765-772
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• 2015

본 연구는 SOFC/GT(Solid Oxide Fuel Cell/Gas Turbine)시스템의 SOFC 스택으로 공급되는 공기, 메탄 및 물의 유량변화에 따른 SOFC/GT시스템의 온도, 스택 출력 및 시스템 효율의 특성에 관하여 조사하였다. 이 때 SOFC 스택의 애노드 및 캐소드로 공급되는 가스 온도는 외부 열원의 추가 없이 시스템에서 배출되는 배기가스를 활용하여 일정하게 유지하였다. 그 결과 본 연구의 범위 내에서 외부 열원의 추가 없이 SOFC/GT시스템의 배기가스를 활용하여 SOFC 스택으로 공급되는 애노드 및 캐소드 가스 공급온도를 1000(K)로 일정하게 유지하는 것이 가능하였다. 시스템 효율은 공급 공기 유량은 많을수록, 공급 메탄 유량은 적을수록 높아짐을 알 수 있었고, 터빈으로 공급되는 배기 가스의 유량이 시스템 효율에 큰 영향을 미침을 알 수 있었다. 또한, SOFC/GT시스템의 운전 조건에 따라서 SOFC 스택 효율은 51~57%, 시스템 효율은 57~73%의 값을 얻을 수 있었다.

• 한국수소및신에너지학회논문집
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• 제24권1호
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• pp.70-75
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• 2013

It has fabricated membrane electrode assemblies (MEA) for proton exchange membrane fuel cell by hot-pressing method. The hot-pressing was used for the fabrication of MEA which is composed of commercial platinum electrode on carbon paper. The performance of MEA was studied with different fabrication conditions of temperature, pressure and torque. As the temperature increased, the performance of MEA was increased. and started to decrease l after arrived at the maximum performance of MEA. This is related with good contact between electrode and polymer electrolyte membrane at high temperature and microstructural change at much higher temperature. Similarly, as the pressure increased, the performance of the MEA increased up to highest values and start to decrease. According to the our results, the maximal performance of the MEA was at the temperature of $140^{\circ}C$ and the pressure of $1.5{\times}10^3$ kPa. The optimal torque to assemble the single stack was 3.2 N m.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1322-1324
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• 2002

For developing a 100 kW MCFC power generation system, Several design parameters for a fuel cell stack and system analysis results by Cycle Tempo, a processing computer soft ware, were described. Approximately 170 cells are required to generate 100 kW at a current density of 125 mA/$cm^2$ with 6000 $cm^2$ cells. An overall heat balance was calculated to predict exit temperature. The 100 kW power is expected only under pressurized operation condition at 3 atm. Recycle of cathode gas by more than 50% is recommended to run the stack at 125 mA/$cm^2$ and 3 atm. Manifolds should be designed based on gas flow rates for the suggested operating condition. The fuel cell power generation system was designed conceptually with several choices of utilization of anode exhaust gas. Also system efficiency was calculated at various type of system and operation conditions.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.87.2-87.2
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• 2010

The steady and dynamic process model for an internal reforming molten carbonate fuel cell power plant is discussed in this paper. The dominant thermal and chemical dynamic processes are modeled for the stack module and balance-of-plant, including cathode gas preparation, heat recovery, heat loss (Each heat loss amount for the stack and MBOP is obtained from real plant data) and fuel processing. Based on dynamic model and control demand, PID controllers are designed in the whole system. By applying these controllers we can obtain temperature balance of stack and control system depending on changing steam to carbon ratio, air feed amount, and transient condition.

• 한국수소및신에너지학회논문집
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• 제28권2호
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• pp.150-155
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• 2017

Proper cooling of PEM fuel cell stack is essential for the high-performance operation of fuel cell system. Insufficient cooling of the stack can cause significant damage to components due to overheating and also can decrease cell performance by dehydration of the polymer electrolyte. In the present study, we performed a computational analysis to assess the condition of the cooling system to secure the proper temperature in fuel cell stack system for high altitude long endurance (HALE) unmanned aerial vehicle (UAV).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1300-1302
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• 2001

For developing a 100 kW MCFC power generation system. Several design parameters for a fuel cell stack and system analysis results by Cycle Tempo, a processing computer soft ware, were described. Approximately 170 cells are required to generate 100 kW at a current density of $125mA/cm^2$ with $6000cm^2$ cells. An overall heat balance was calculated to predict exit temperature. The 100 kW power is expected only under pressurized operation condition at 3 atm. Recycle of cathode gas by more than 50% is recommended to run the stack at $125mA/cm^2$ and 3 atm. Manifolds should be designed based on gas flow rates for the suggested operating condition. The fuel cell power generation system was designed conceptually with several choices of utilization of anode exhaust gas. Also system efficiency was calculated at various type of system and operation conditions.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.911-913
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• 2008

In this work, nonvolatile memory (NVM) devices for system on panel of flat panel display (FPD) were fabricated using low temperature polycrystalline silicon (LTPS) thin film transistor (TFT) technology with an oxide-nitride-oxynitride (ONOn) stack structure on glass. The results demonstrate that the NVM devices fabricated using the ONOn stack structure on glass have suitable switching characteristics for data storage with a low operating voltage, a threshold voltage window of more than 1.8 V between the programming and erasing (P/E) states after 10 years and its initial threshold voltage window (${\Delta}V_{TH}$) after $10^5$ P/E cycles.

• 설비공학논문집
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• 제20권3호
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• pp.197-204
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• 2008

DMFC(Direct Methanol Fuel Cell) is one of promising candidates for power sources of small mobile IT devices like notebook, cell phone, and so on. Efficient operation of fuel cell system is very important for long-sustained power supply because of limited fuel tank size. It is necessary to investigate operation characteristics of fuel cell stack for optimal control of DMFC system. The generated voltage was modeled according to various operating condition; methanol concentration, stack temperature, and load current. It is inevitable for methanol solution at anode to cross over to cathode through MEA(membrane electrode assembly), which reduces the system efficiency and increases fuel consumption. In this study, optimal operation conditions are proposed by analyzing stack performance model, cross-over phenomenon, and system efficiency.