• Transactions on Electrical and Electronic Materials
• /
• v.8 no.6
• /
• pp.286-288
• /
• 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 $850mA/cm^2$.

• Journal of Navigation and Port Research
• /
• v.45 no.5
• /
• pp.231-237
• /
• 2021

Enhancing the performance of maritime wireless communication has been highlighted by the issue of cell planning in the sea area because of lack of an appropriate Propagation Loss Model (PLM). To resolve the cell planning issue in vast sea areas, it was essential to develop the (PLM) matching the intended sea area. However, there were considerable gaps between the prediction of legacy PLMs and field measurement in propagation loss and there was a need to develop the adjusted PLM (A-PLM). Therefore, cell planning was performed on this adjusted model, including modification of the base station's location, altitude, and antenna azimuth to meet the quality objectives. Furthermore, in order to verify the availability of the cell planning, Communication Service Quality Monitoring System (CS-QMS) was developed in the LTE-Maritime project to collect LTE signal quality information from the onboard equipment at regular intervals and to ensure that the service quality was high enough to satisfy the goals in each designated grid. As a result of verification, the success rate of RSRP was 95.7% for the intensive management zone (IMZ) and 96.4% for the interested zone (IZ), respectively.

• Transactions of the Korean hydrogen and new energy society
• /
• v.24 no.6
• /
• pp.480-486
• /
• 2013

In this study, tubular SOFC unit cell with advanced anode current collector was fabricated to improve the cell performance. First, we prepared two types of single cells having the same manufacture processes such as the same electrolyte, electrode coating condition and sintering processes. And then to compare the developed single cell performance with conventional cells, we changed the anode current collecting methods. From the impedance analysis and I-V curve analysis, the cell performance of advanced cell is much higher than that of conventional cell.

• Journal of the Korean Ceramic Society
• /
• v.42 no.4
• /
• pp.269-275
• /
• 2005

We analyzed the unit cell performance against the cathode porosity, which is supposed to be closely related with active sites for the cathode reaction. In order to fabricate the unit cells with different porosity in the cathode layer we changed the mixing ratio of fine and coarse LSCF cathode powders. The final porosity of each cathode layer was 14, 23, 27, $39\%$ respectively. According to the electrochemical analysis of unit cell performance via DC current interruption and AC impedance method, the electrodic polarization resistance was diminished as the cathode porosity increased. The decrease of polarization resistance was attributed due to the increase of active reaction sites and the enhancement of overall unit cell performance could be explained in the same line.

• Advances in Energy Research
• /
• v.8 no.4
• /
• pp.203-211
• /
• 2022

The aim of this paper is to analyze the performance of commercial fuel cell (rated capacity 1000W) with the help of resistive load and output power variation with change in H₂ flow rate and calculate the maximum power point (MPP) of the proton exchange membrane (PEM) while changing AC and DC load respectively. The factors influencing the output power of a fuel cell are hydrogen flow rate, cell temperature, and membrane water content. The results show that when the H₂ flow rate is changed from 11, 13, and 15 Lpm, MPP is increased from lower to higher flow rate. The power of the fuel cell is increased at the rate of 29% by increasing the flow rate from 11 to 15 lpm. This study will allow small-scale industries and residential buildings (in remote or inaccessible areas) to characterize the performance of PEMFC. Furthermore, fuel cell helps in reducing emission in the environment compared to fossil fuels. Also, fuel cells are ecofriendly as well as cost effective and can be the best alternative way to convert energy.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.23 no.1
• /
• pp.49-55
• /
• 2015

In this study, among in various scenarios of the duration degradation of the fuel cell, countermeasures for the cathode carbon carrier oxidation and the deactivation of catalyst by hydrogen / air interface formation have been studied. so the system was applied to the air cutoff valve. In terms of the component, the cold start performance, electrical stability, the airtight performance were mainly designed and their performance was confirmed. And in terms of the system, the air electrode flow is blocked off, so the oxygen concentration drops when system is powered off, As a result, By reducing unit cell voltage which affect the durability of the fuel cell reached up to 0.8V, the improved durability of the fuel cell was confirmed.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.35 no.6
• /
• pp.593-601
• /
• 2011

An analysis program to simulate the operation of a polymer electrolyte membrane fuel cell (PEMFC) system was set up, and system operation with variations in the working conditions of various components (especially the thermal management system) was simulated. The entire system included a PEMFC stack and balance-of-plant components such as an air-supply unit, a fuel-supply unit, and a heat-management unit (cooling system). Thermodynamic models of all components were made to evaluate the design performance of the entire system, and then off-design models were set up to simulate the operation of the entire system under arbitrary working conditions. A parametric study was carried out to examine the effects of varying the operating conditions (especially the ambient conditions and the operating conditions of the cooling system) on the operation and performance of the entire system.

• Journal of the Korean Electrochemical Society
• /
• v.7 no.2
• /
• pp.69-79
• /
• 2004

To correctly simulate performance characteristics of fuel cells with a modeling method, various physical and chemical phenomena must be considered in fuel cells. In this study, performance characteristics of planar solid oxide fuel cells were simulated by a commercial CFD code, CFD-ACE+. Through simultaneous considerations for mass transfer, heat transfer and charge movement according to electrochemical reactions in the 3-dimensional planar SOFC unit stack, we could successfully predict performance characteristics of solid oxide fuel cells under operation for structural and progress variables. In other words, we solved mass fraction distribution of reactants and products for diffusion and movement, and investigated qualitative and quantitative analysis for performance characteristics in the SOFC unit stack through internal temperature distribution and polarization curve for electrical characteristics. Through this study, we could effectively predict performance characteristics with variables in the unit stack of planar SOFCs and present systematic approach for SOFCs under operation by computer simulation.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.123.1-123.1
• /
• 2010

The solid oxide fuel cell (SOFC) has attracted great deal of attention due to its high electrical efficiency, high waste-heat utilization, fuel flexibility, and application versatility. However, SOFC technology is still not matured enough to fulfill the practical requirements for commercialization. Therefore, all the research and development activities are mainly focused on a development of practically viable SOFCs with higher performance and better reliability. We were successful in fabricating high-performance anode-supported unit cells by employing hierarchically controlled multi-layered electrodes for both structural reliability and high performance. In addition, a novel composite sealing gasket made it possible to achieve excellent sealing integrity even with considerable surface irregularities in a multi-cell planar arrayed stack.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.4
• /
• pp.75-80
• /
• 2005

An experimental study is carried out to investigate the performance and the efficiency humidifying Membrane Electrolyte Assembly and having the double-tied catalyst layers in a fuel cell system which is taken into account the physical and thermal concept. Subsequently, an electric output produced by PEMFC(Polymer Electrolyte Membrane Fuel Cell) is measured to assess the performance of a stack, and the efficiency is also evaluated according to the different situation in which unit cell is placed with and without the humidification of the MEA. It is found that the measured values of stack voltage and current are influenced by the stack temperature, humidification, and the double-tied catalyst layers which give more enhanced values to be applied to electric units.