• Journal of Hydrogen and New Energy
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• v.21 no.2
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• pp.143-148
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• 2010

Research and Development (R&D) investment of hydrogen and fuel cell, funded by government from 2007 to 2008 in Korea, has been analyzed. R&D investment of hydrogen and fuel cell in 2008 would see 9% and 29% of total budget in the field of renewable energy, respectively. It was found that R&D investment is mainly dependent on mission of Ministry in Korea. Basic and apply research would be mainly invested by Ministry of Education, Science and Technology (MEST), while development research would be conducted by Ministry of Knowledge Economy (MKE). In R&D investment by performer, hydrogen technology would be conducted by government-funded institute and university. It was also shown that funds for hydrogen production have been much supported than hydrogen storage. Meanwhile, fuel cell would be mainly conducted by major companies. It was also shown that funds for proton exchange membrane fuel cell (PEMFC) have been much invested than other technology in fuel cell.

• Polymer(Korea)
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• v.34 no.3
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• pp.202-209
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• 2010

Aromatic copolyamides were prepared and their applicability to proton exchange membrane wasstudied. The copolymer contains thermally stable and mechanically strong poly(m-phenylene isophthalamide) segments, and easily processable and good film forming polysulfone segments. For the copolymer, amineterminated sulfonated ether sulfone monomer, m-phenylene diamine, and isophthaloyl chloride were reacted, and the obtained copolymer was transformed into crosslinkable prepolymer by the reaction with acryloyl chloride. The prepolymer was thermally cured and converted into proton exchange membranes for fuel cell application. Each reaction step and the molecular characteristics of precursor copolymers were monitored and confirmed by $^1H$ NMR, FTIR, and titration. The performance of the membranes was measured in terms of water uptake, proton conductivity, and thermal stability. The water uptake, ion exchange capacity (IEC), and proton conductivity of the membranes increased with the increase of sulfonated ether sulfone segment content. Membrane containing 30 mol% sulfonic acid sulfone segment showed 1.57 meq/g IEC value. Water uptake was limited less than 44 wt% and the highest proton conductivity up to $3.93{\times}10^{-2}S/cm$ ($25^{\circ}C$, RH= 100%) was observed.

• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.91-97
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• 2014

This paper proposes a modeling of fuel cell which replaces dc source during simulation. Fuel cells are electrochemical devices that convert chemical energy in fuels into electrical energy. This system has high efficiency and heat, no environmental chemical pollutions and noise. Proton exchange membrane fuel cells (PEMFC) are commonly used as a residential generator. These fuel cells have different electrical characteristics such as a low voltage and high current compared with solar cells. And there are different behaviors in the V-I curve in the temperature and pressure. Therefore, the modeling of fuel cell should consider wide voltage range and slow current response and the resulting electrical model is applied to boost converter with fuel cell as an input source.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.315-319
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• 2018

Fenton reaction is widely used as a out of cell method for evaluating the membrane electrochemical durability of Proton Exchange Fuel Cell (PEMFC). In this study, we investigated the factors affecting the Fenton reaction. In order to estimate the degree of the reaction, it is necessary to analyze the radicals as a product in the Fenton reaction. However, since the radicals are difficult to analyze, the degree of the reaction was measured by analyzing the concentration of hydrogen peroxide. The activation energy was calculated from the rate of hydrogen peroxide change with temperature. The activation energy was 24.9 kJ/mol at 180 min. The Fenton reaction rate was affected by the iron ion concentration. At $80^{\circ}C$, 200 rpm, and $Fe^{2+}$ 80 ppm, the concentration of hydrogen peroxide was decreased more than 20% even for 1 hour, which shows that frequent solution replacement increases the membrane degradation rate.

• Journal of the Korean Electrochemical Society
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• v.12 no.1
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• pp.61-67
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• 2009

Flow-field design has much influence over the performance of proton exchange membrane fuel cell (PEMFC) because it affects the pressure magnitude and distribution of the reactant gases. To obtain the pressure magnitude and distribution of reactant gases in five kinds of flow-field designs, computational fluid dynamics (CFD) analysis was performed. After the CFD analysis, a single cell test was carried out to obtain the performance values. As expected, the pressure differences due to different flow-field configurations were related to the PEMFC performance because the actual performance results showed the same tendency as the results of the CFD analysis. A large pressure drop resulted in high PEMFC performance. The single serpentine configuration gave the highest performance because of the high pressure difference magnitudes of the inlet/outlet. On the other hand, the parallel flow-field configuration gave the lowest performance because the pressure difference between inlet and outlet was the lowest.

• Journal of the Korean Solar Energy Society
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• v.32 no.spc3
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• pp.275-281
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• 2012

Proton Exchange Membrane Fuel Cells (PEMFC) are the most appropriate for energy source of small robot applications. PEMFC has superior in power density and thermodynamic efficiency as compared with the Direct Methaol Fuel Cell (DMFC). Furthermore, PEMFC has lighter weight and smaller size than DMFC which are very important factors as small robot power system. The most significant factor of mobile robots is weight which relates closely with energy consumption and robot operation. This research tried to find optimum specifications in terms of type, number of cell, active area, cooling method, weight, and size. In order to find optimum 500W PEMFC, six options are designed in this paper and studied to reduce total stack weight by applying new materials and design innovations. However, still remaining problems are thermal management, robot space for energy sources, and soon. For a thermal management, design options need to analysis of Computational Fluid Dynamics (CFD) for determining which option has the improved performance and durability.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.211-216
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• 2012

Proton Exchange Membrane Fuel Cells (PEMFC) are the most appropriate for energy source of small robot applications. PEMFC has superior in power density and thermodynamic efficiency as compared with the Direct Methaol Fuel Cell (DMFC). Furthermore, PEMFC has lighter weight and smaller size than DMFC which are very important factors as small robot power system. The most significant factor of mobile robots is weight which relates closely with energy consumption and robot operation. This research tried to find optimum specifications in terms of type, number of cell, active area, cooling method, weight, and size. In order to find optimum 500W PEMFC, six options are designed in this paper and studied to reduce total stack weight by applying new materials and design innovations. However, still remaining problems are thermal management, robot space for energy sources, and so on. For a thermal management, design options need to analysis of Computational Fluid Dynamics (CFD) for determining which option has the improved performance and durability.

• Journal of Electrochemical Science and Technology
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• v.15 no.3
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• pp.373-387
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• 2024

The layout of the cathode flow field largely determines the net output power of the proton exchange membrane fuel cell (PEMFC). To make the normal mass transfer effect best, the longitudinal channel was waved based on four serpentine flow channels, and the effects of sag depth and longitudinal channel width on the output efficiency of the cell were explored. The results show that the wave channel design systematically enhances the forced convection between adjacent channels, which can prevent a large zone of oxygen starvation zone at the outlet of the channel. The increase of the normal velocity in the gas transmission process will inevitably induce a significant enhancement of the mass transfer effect and obtain a higher current density in the reaction zone. For the longitudinal channel width, it is found that increasing its size in the effective range can greatly reduce the channel pressure drop without reducing the output power, thereby improving the overall efficiency. When the sag depth and longitudinal channel width gradient are 0.6 mm and 0.2 mm respectively, PEMFC can obtain the best comprehensive performance.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.12
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• pp.1188-1193
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• 2007

This study focuses on the corrosion problems of STS316(stainless steel 316) tube for the cooling system of PEMFC (Proton Exchange Membrane Fuel Cell) operation. Deionized water which is highly corrosive is used especially for cooling agent of PEMFC to eliminate electrical conductivity, The tensile stress analysis was performed to check the change of mechanical strength of cooling line and pH of the water was monitored for the observation of extent of corrosion at simulated PEMFC operating condition. When STS316 tube was exposed to deionized water for 500 hours, substantial cracks were found on the surface and the pH of water was decreased from 6.8 to 5.8. For prevention of corrosion problems, the STS316 was coated by three kinds of fluororesin such as PTFE, FEP and ETFE. Among the coating materials, PTFE was the most protective in corrosive environment and was maintained the mechanical strength. To lower the cost, the same experimental analyses were carried out for iron tubes and the result will be discussed in detail.

• Journal of Surface Science and Engineering
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• v.50 no.1
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• pp.1-9
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• 2017

Design of novel materials in renewable energy systems plays a key role in powering transportation vehicles and portable electronics. This review introduces the research work of first principles-based computational design for the materials over the last decade to accomplish the goal with less financial and temporal cost beyond the conventional approach, especially, focusing on electrocatalyst toward a proton exchange membrane fuel cell (PEMFC). It is proposed that the new method combined with experimental validation, can provide fundamental descriptors and mechanical understanding for optimal efficiency control of a whole system. Advancing these methods can even realize a computational platform of the materials genome, which can substantially reduce the time period from discovery to commercialization into markets of new materials.