• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.484-496
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• 2009

The strengthened regulations for atmospheric emissions from ships like MARPOL Annex VI have caused a necessity of new, alternative power system in ships for the low pollutant emissions and the high energy efficiency. This paper attempts to investigate the configuration of SOFC/GT hybrid power system for LNG tanker taking into account the safety and to analyze the influence of design parameters on the system performance. The simulation results provide the basic data for the design and efficiency improvement of SOFC/GT hybrid system and indicate the guidelines for the safe system operation.

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.528-532
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• 1997

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 SOFC, by the way, Ni-YSZ materials are used as anode of SOFC widely. So in this experiments, we investigated the optimum content of Ni, by testing expansion coefficient, impedance characteristics, overvoltage. As a result, the performance of Ni-YSZ anode(40vol%) was better excellent than the others.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1013-1020
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• 2004

The hybrid system of gas turbine and fuel cell is expected to produce electricity more efficiently than conventional methods, especially in small power applications such as distributed generation. The solid oxide fuel cell (SOFC) is currently the most promising fuel cell for the hybrid system. To realize the conceptual advantages resulting from the hybridization of gas turbine and fuel cell, optimized construction of the whole system must be the most important. In this study, parametric design analyses for pressurized GT/SOFC systems have been peformed considering probable practical limiting design factors such as turbine inlet temperature, fuel cell operating temperature, temperature rise in the fuel cell and soon. Analyzed systems include various configurations depending on fuel reforming type and fuel supply method.

• Journal of the Korean Ceramic Society
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• v.39 no.1
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• pp.86-91
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• 2002

Solid Oxide Fuel Cells (SOFC) are of great interest of next generation energy conversion system due to their high energy efficiency and environmental friendliness. The basic SOFC unit consists of anode, cathode and solid electrolyte. Among these components, anode plays the most important role for the oxidation of fuel to generate electricity and also behaves as a substrate of the whole cell. It is normally requested that the anode materials should have the high electrical conductivity and gas permeability to reduce the polarization loss of the cell. In this study, the effect of pore former on the microstructure of anode substrate was investigated and thus on the electrical conductivity and the gas permeability. According to the results, microstructure and electrical conductivity of anode substrate were greatly influenced by the shape of pore former and especially by the anisotrpy of the pore former. The use of anisotropic pore former is supposed to deteriorate the cell performance by which the electrical conduction path is disconnected but also the effective gas diffusion path for the fuel is reduced.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.13-16
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• 2008

Solid oxide fuel cell(SOFC) is an electrochemical energy conversion system with high efficiency and low-emission of pollution. In order to reduce the operating temperature of SOFC system under $800^{\circ}C$, the thickness reduction of YSZ electrolyte to be as thin as possible, e.g., less than 10 ${\mu}m$ are considered with the microstructure control and optimum design of unit cell. Methods for reducing the thickness of YSZ electrolyte have been investigated in coin cell. Moreover, a large unit cell($8cm{\times}8cm$) for SOFC was fabricated using an anode-supported electrolyte assembly with a thinner electrolyte layer, which was prepared by a tape casting method with a co-sintering technique. we studied the design factors such as active layer, electrolyte thickness, cathode composition, etc,. by the coin type of unit cell ahead of the fabrication process of a large unit cell and also reviewed about the evaluation technique of a large size unit cell such as interconnect design, sealing materials and current collector and so forth. Electrochemical evaluations of the unit cells, including measurements such as power density and impedance, were performed and analyzed. Maximum power density and polarization impedance of coin cell were 0.34W/$cm^2$ and $0.45{\Omega}cm^2$ at $800^{\circ}C$, respectively. However, Maxium power density of a large unit cell($5cm{\times}5cm$) decreased to 0.21W/$cm^2$ at $800^{\circ}C$ due to the increase of ohmic resistance. However, It was found that the potential value of a large unit cell loaded by 0.22A/$cm^2$ showed 0.76V at 100hrs without the degradation of unit cell.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.562-566
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• 2012

A novel design of tubular segmented-in-series(SIS) solid oxide fuel cell (SOFC) sub module was presented in this paper. The tubular ceramic support was fabricated by the extrusion technique. The NiO-YSZ anode and the yttria-stabilized zirconia (YSZ) electrolyte were deposited onto the ceramic support by dip coating method. After sintering at $1350^{\circ}C$ for 5 h, a dense and crack-free YSZ film was successfully fabricated. Also, the multi-layered cathode composed of LSM-YSZ composite, LSM and LSCF were coated onto the sintered ceramic support by dip coating method and sintered at $1150^{\circ}C$. The performance of the tubular SIS SOFC cell and sub module electrically connected by the Ag-glass interconnect was measured and analysed with different fuel flow and operating temperature.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.1
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• pp.40-47
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• 2024

Ammonia is drawing attention as carbon free fuel due to its ease of storage and transportation compared to hydrogen. This study suggests ammonia fueled solid oxide fuel cell (SOFC) system with electrochemical hydrogen compressor (EHC)-based recirculation. Performance of electrochemical hydrogen pump is based on the experimental data under varying hydrogen and nitrogen concentration. As a result, the suggested system shows 62.04% net electrical efficiency. The efficiency is 10.33% point higher compared to simple standalone SOFC system (51.71%), but 0.02% point lower compared to blower-based recirculation system (62.06%). Further improvement in the EHC-based SOFC recirculation system can be achieved with EHC performance improvement.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.373-380
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• 2001

Solid Oxide Fuel Cells (SOFCs) have received considerable attention because of the advantages of high effiiciency, low pollution, cogeneration application and excellent integration with simplified reformer In this paper, we reported development of anode-tubular SOFC by wet process. For making tubular cell, Ni-cermet YSZ anode tube was fabricated using extrusion process, and YSZ electrolyte layer and LSM-YSZ composite, LSM, LSCF cathode layer were coated onto the anode supported tube using slurry dipping process and sintered by co-firing process. By using this tubular cell, we fabricated single cell consisted of the various cathode layers and 4 cell stack with an effective area of $75 cm^2$ per single cell, and evaluated their performance characteristics.

• Journal of Electrochemical Science and Technology
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• v.12 no.1
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• pp.159-165
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• 2021

YSZ based anode supported solid oxide fuel cells (SOFCs) were prepared, and two cells with different electrolyte thicknesses were connected in series for the simulation of a cell-imbalanced fuel cell stack. Pure YSZ cells in a series connection exhibited a rapid degradation when a thick electrolyte cell was operated under a negative voltage. On the other hand, ceria added-YSZ cells in a series connection were stable under similar operating conditions, and the power density and impedance were about the same as those before tests. The improved stability was due to the reduction of internal partial pressure in the electrolyte by locally increasing the electronic conduction. Thus, we propose a new protection method, i.e., the local addition of ceria in the YSZ electrolyte, to extend the lifetime of a cell-imbalanced SOFC stack.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.91.1-91.1
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• 2011

고체산화물 연료전지(Solid Oxide Fuel Cell이하 SOFC)는 연료가 갖는 화학에너지를 연소과정 없이, 공기와 H2, CO, CH4와 같은 환원성 가스를 공급받아 $600{\sim}1000^{\circ}C$에서 전기화학적 반응을 통하여 직접 전기를 얻는 방식이다. SOFC는 $700^{\circ}C$ 이상의 고온에서 고체산화물이 연료와 공기가 반응하여 전기와 열을 동시에 생산하기 때문에 carnot cycle의 제한을 받지 않아 발전효율이 40% 이상으로 고효율이고, NOx 및 SOx를 배출하지 않아 무공해이며, moving parts가 없어 소음이 나지 않고, 건설과 증설이 지역이나 기후 조건에 제약 없이 용이하고, 다양한 용량이 가능하며, 고가의 백금 촉매를 사용하지 않으며, 수소, 석탄가스, 천연가스 등의 연료를 사용할 수 있는 장점이 있음, 또한 다향한 형태로 제작할 수 있으며 전해질이 고체에서 전해질 손실 및 보충에 문제가 없고 타 연료전지에 비해 개질기가 필요 없어 발전시스템이 간단하고 경량화가 가능하다. 전사법은 paste를 제작하여 전사용지에 Screen printing하여 건조 후 coating하는 방법으로 기존의 여러 coating 방법보다 제작이 용이하고 소재의 크기, 두께조절이 간편하며, 구성층의 표면조도나 굴곡에 대응이 용이한 방법이다. 본 실험에서는 paste 제조, 전사법을 이용하여 Anode, AFL, Electrolyte, CFL, Cathode전사지를 제작하고 이를 세라믹 평관형 지지체에 변수로 두께 조건별 Coating 한 후 $1400^{\circ}C$ 소결을 진행하여 SEM 분석으로 미세구조 관찰, 출력특성 및 Impedance을 확인하였다.