• Journal of the Korean Electrochemical Society
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• v.6 no.3
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• pp.183-186
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• 2003

In a PEM fuel cell electrode, backing layer has tremendous impact on electrode performance. The backing layer provides structural support for the porous electrode, distributes the reactants to the other layers and acts as a current collector. It has major influence on the water management in a PEM fuel cell. Selection of suitable backing layer material for the fabrication of electrode is thus very important to achieve high performance. In this paper we have compared the performance of PEM fuel cell electrodes fabricated using carbon paper EC-TPI-060T, carbon cloth EC-CCI-060T, (ElectroChem Inc.USA) and Carbon cloth from Textron, USA (CPW 003 grade). Mass transport problem was observed under non-pressurized condition, at high current densities, in the caie of EC-CC1-060T carbon cloth electrode (at $50^{\circ}C$), due to its higher thickness. The performance of carbon paper electrode was higher than EC-CCI-060T carbon cloth electrode. The performance of Textron carbon cloth was comparable to EC-TPI -060T carbon paper.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.12
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• pp.2161-2166
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• 2008

This paper deals with a Z-source active power filter(Z-AFU) for mitigation voltage THD(total harmonic distortion) due to voltage harmonic propagation(amplification) in 6.6kv power distribution system. Bus voltage harmonic signal is detected by 60Hz butterworth BPF(band pass filter). As an ESS(energy storage system) of the proposed system, PEM fuel cells(Ballard NEXA, 1.2kw) is employed. Test results based on PSIM(power electronics simulation tool) validate the proposed approach.

• Journal of computational fluids engineering
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• v.12 no.1
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• pp.9-15
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• 2007

A three dimensional numerical model to predict the flow and transport of mixtures and also the electrochemical reactions in polymer electrolyte membrane (PEM) fuel cells is developed. The numerical computation is base on vorticity- velocity method. Governing equations for the flow and transport of mixtures are coupled with the equations for electrochemical reactions and are solved simultaneously including production and condensation of vapor. Fuel cell performance predicted by this calculation is compared with the experimental results and resonable agreements are achieved.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.553-554
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• 2006

This paper presents the effects of different operating parameters on the performance of a proton exchange membrane (PEM) fuel cell by a three-dimensional computational fluid dynamics (CFD) model. The effects of different operating parameters on the performance of PEM fuel cell studied using pure hydrogen on the anode side and air on the cathode side. The various parameters are temperatures, pressures, humidification of the gas steams and various combinations of these parameters. In addition, geometrical and material parameters such as the gas diffusion layer (GDL) thickness and porosity as well as the ratio between the channel width and the land area were investigated.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.39-46
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• 2006

The fuel cell is one of promising environment-friendly energy sources for the next generation. The bipolar plate is a major component of the PEM fuel cell stack, which takes a large portion of stack cost. In this study, as alternative materials for bipolar plate of PEM fuel cells, graphite composites were fabricated by compression molding. Graphite particles mixed with epoxy resin were used as the main substance to provide electric conductivity To achieve desired electrical properties, specimens made with different mixing ratio, processing pressure and temperature were tested. To increase mechanical strength, one or two layers of woven carbon fabric were added to the graphite and resin composite. Thus, the composite material was consisted of three phases: graphite particles, carbon fabric, and epoxy resin. By increasing mixing ratio of graphite, fabricated pressure and process temperature, the electric conductivity of the composite was improved. The results of tensile test showed that the tensile strength of the two-phase graphite composite was about 4MPa, and that of three-phase composite was increased to 57MPa. As surface properties, contact an91e and surface roughness were tested. Graphite composites showed contact angles higher than $90^{\circ}$, which mean low surface energy. The average surface roughness of the composite specimens was $0.96{\mu}m$.

• International Journal of Automotive Technology
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• v.1 no.1
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• pp.9-16
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• 2000

The growing concerns on environmental protection have been constantly demanding cleaner and more energy efficient vehicles without compromising any conveniences provided by the conventional vehicles. The recent significant advances in proton-exchange-membrane (PEM) fuel cell technology have shown the possibility of developing such vehicles powered by fuel cells. Several prototype fuel cell electric vehicles (FCEV) have been already developed by several major automotive manufactures, and all of the favorable features have been demonstrated in the public roads. FCEV is essentially a zero emission vehicle and allows to overcome the range limitation of the current battery electric vehicles. Being motivated by the laboratory and field demonstrations of the fuel cell technologies, variety of fuel cell alliances between fuel cell developers, automotive manufactures, petroleum companies and government agencies have been formed to expedite the realization of commercially viable FCEV. However, there still remain major issues that need to be overcome before it can be fully accepted by consumers. This paper describes the current fuel cell vehicle development status and the staggering challenges for the successful introduction of consumer acceptable FCEVS.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.563-567
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• 2009

The polymer electrolyte membrane fuel cell(PEMFC) with the advantages of low-operating temperature, high current density, low cost and volume, fast start-up ability, and suitability for discontinuous operation becomes the most reasonable and attractive power system for transportation vehicle and micro-grid power plant in a household. 200W PEM-type FCs system was integrated by this study, then the electrical characteristics and diagnosis of the fuel cell were analyzed with variations on mass flow rate and stack temperature. The ranges of the variations are 1~8L/min on $H_2$ volume and $20{\sim}70^{\circ}C$ on stack temperature.

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

• Membrane Journal
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• v.33 no.6
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• pp.325-343
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• 2023

Direct methanol fuel cells (DMFCs) have been attracting attention as energy conversion devices that can directly supply methanol liquid fuel without a fuel reforming process. The commercial polymer electrolyte membranes (PEMs) currently applied to DMFC are perfluorosulfonic acid ionomer-based PEMs, which exhibit high proton conductivity and physicochemical stability during the operation. However, problems such as high methanol permeability and environmental pollutants generated during decomposition require the development of PEMs for DMFCs using novel ionomers. Recently, studies have been reported to develop PEMs using hydrocarbon-based ionomers that exhibit low fuel permeability and high physicochemical stability. This review introduces the following studies on hydrocarbon-based PEMs for DMFC applications: 1) synthesis of grafting copolymers that exhibit distinct hydrophilic/hydrophobic phase-separated structure to improve both proton conductivity and methanol selectivity, 2) introduction of cross-linked structure during PEM fabrication to reduce the methanol permeability and improve dimensional stability, and 3) incorporation of organic/inorganic composites or reinforcing substrates to develop reinforced composite membranes showing improved PEM performances and durability.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.55.2-55.2
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• 2009

A polymer electrolyte membrane (PEM) fuel cell has been getting large interest as a typical issue in useful applications. The PEMFC is composed of a membrane, catalyst and the bipolar plate. SnOx:F films on SUS316 stainless steel were prepared as a function of substrate with using electron cyclotron resonance-metal organic chemical vapor deposition (ECR-MOCVD) in order to achieve the corrosion-resistant and low contact resistance bipolar plates for PEM fuel cells. The SnOx:F films coated on SUS316 substrate at surface plasma treatment for excellent stability, before/after heat treatment for good crystalline structure and microwave power for were characterized by X-ray diffraction (XRD), auger electron microscopy (AES) and field emission-scanning electron microscopy (FE-SEM). The SnOx:F film coated on SUS316 substrate with various process parameters were able to observe optimum interfacial contact resistance (ICR) and corrosion resistance. It can be concluded that fluorine-doping content plays an important function in electrical property and characteristic of corrosion-protective film.