Dissertations / Theses: 'Fuel cells research'

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Clarke, Adrian James. "The conceptual design of novel future UAV's incorporating advanced technology research components." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/7163.

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There is at present some uncertainty as to what the roles and requirements of the next generation of UAVs might be and the configurations that might be adopted. The incorporation of technological features on these designs is also a significant driving force in their configuration, efficiency, performance abilities and operational requirements. The objective of this project is thus to provide some insight into what the next generation of technologies might be and what their impact would be on the rest of the aircraft. This work involved the conceptual designs of two new relevant full-scale UAVs which were used to integrate a select number of these advanced technologies. The project was a CASE award which was linked to the Flaviir research programme for advanced UAV technologies. Thus, the technologies investigated during this study were selected with respect to the objectives of the Flaviir project. These were either relative to those already being developed as course of the Flaviir project or others from elsewhere. As course of this project, two technologies have been identified and evaluated which fit this criterion and show potential for use on future aircraft. Thus we have been able to make a contirubtion knowledge in two gaps in current aerospace technology. The first of these studies was to investigate the feasibility of using a low cost mechanical thrust vectoring system as used on the X-31, to replace conventional control surfaces. This is an alternative to the fluidic thrust vectoring devices being proposed by the Flaviir project for this task. The second study is to investigate the use of fuel reformer based fuel cell system to supply power to an all-electric power train which will be a means of primary propulsion. A number of different fuels were investigated for such a system with methanol showing the greatest promise and has been shown to have a number of distinct advantages over the traditional fuel for fuel cells (hydrogen). Each of these technologies was integrated onto the baseline conceptual design which was identified as that most suitable to each technology. A UCAV configuration was selected for the thrust vectoring system while a MALE configuration was selected for the fuel cell propulsion system. Each aircraft was a new design which was developed specifically for the needs of this project. Analysis of these baseline configurations with and without the technologies allowed an assessment to be made of the viability of these technologies. The benefits of the thrust vectoring system were evaluated at take-off, cruise and landing. It showed no benefit at take-off and landing which was due to its location on the very aft of the airframe. At cruise, its performance and efficiency was shown to be comparable to that of a conventional configuration utilizing elevons and expected to be comparable to the fluidic devices developed by the Flaviir project. This system does however offer a number of benefits over many other nozzle configurations of improved stealth due to significant exhaust nozzle shielding.The fuel reformer based fuel cell system was evaluated in both all-electric and hybrid configurations. In the ell-electric configuration, the conventional turboprop engine was completely replaced with an all-electric powertrain. This system was shown to have an inferior fuel consumption compared to a turboprop engine and thus the hybrid system was conceived. In this system, the fuel cell is only used at loiter with the turboprop engine being retained for all other flight phases. For the same quantity of fuel, a reduction in loiter time of 24% was experienced (compared to the baseline turboprop) but such a system does have benefits of reduced emissions and IR signature. With further refinement, it is possible that the performance and efficiency of such a system could be further improved. In this project, two potential technologies were identified and thoroughly analysed. We are therefore able to say that the project objectives have been met and the project has proven worthwhile to the advancement of aerospace technology. Although these systems did not provide the desired results at this stage, they have shown the potential for improvement with further development.

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Jackson, Colleen. "SiC and B₄C as electrocatalyst support materials for low temperature fuel cells." Doctoral thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27313.

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Supported nano-catalyst technologies are key for increasing the catalyst utilisation and achieving economically feasible platinum metal loadings in hydrogen polymer electrolyte fuel cells (PEFCs). High surface area carbons are commonly utilised as support materials for platinum due to low cost, large surface areas and high conductivity. However, PEFCs using this technology undergo oxidation of carbon supports, significantly reducing the lifetime of the fuel cell. In this work, silicon carbide and boron carbide are investigated as alternative catalyst support materials to carbon, for the oxygen reduction reaction for low temperature fuel cells. Electrochemical testing, accelerated degradation studies as well as advanced characterisation techniques were used to clarify the structure-property relationships between catalyst morphology, metal-support interaction, ORR activity and surface adsorption onto the Pt nanoparticles. Extended X-ray Absorption Fine Structure (EXAFS) analysis gave insights into the shape of the clustered nanoparticles while X-ray Photoelectron Spectroscopy (XPS) and in-situ X-ray Absorption Near-Edge Spectroscopy (XANES) analysis provided information into how the metal-support interaction influences surface adsorption of intermediate species. Electronic metal-support interactions between platinum and the carbide supports were observed which influenced the electrochemical characteristics of the catalyst, in some cases increasing the oxygen reduction reaction activity, hydrogen oxidation reaction activity and Pt stability on the surface of the support.

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Jackson, Colleen. "Preparation and characterisation of Pt-Ru/C catalysts for direct methanol fuel cells." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/24322.

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The direct methanol fuel cell (DMFC) is identified as a promising fuel cell for portable and micro fuel cell applications. One of the major benefits is that methanol is an energy dense, inexpensively manufactured, easily stored and transported, liquid fuel (Hamann et al., 2007). However, the DMFC's current efficiency and power density is much lower than theoretically possible. This inefficiency is predominantly due to the crossover of methanol from the anode to the cathode, Ru dissolution and Ru crossover from the anode to the cathode. In addition, the DMFC has a high manufacturing cost due to expensive catalyst costs and other materials. Catalyst expenses are further increased by catalyst loading due to low activity at the anode of the DMFC (Zhang, 2008). Hence, with increasing activity and stability of the Pt-Ru/C catalyst, catalyst expenditure will decrease due to a decrease in catalyst loading. In addition, performance will increase due to a reduction in ruthenium dissolution and crossover. Therefore, increasing the activity and stability of the Pt-Ru/C catalyst is paramount to improving the current DMFC performance and viability as an alternative energy conversion device. Pt-Ru/C catalyst synthesis method, precursors, reduction time and temperature play a role in the activity for methanol electro-oxidation and stability since these conditions affect structure, morphology and dispersivity of the catalyst (Wang et al., 2005). Metal organic chemical deposition methods have shown promise in improving performance of electro-catalysts (Garcia & Goto, 2003). However, it is necessary to optimise deposition conditions such as deposition time and temperature for Pt(acac)₂ and Ru(acac)₃ precursors. This study focuses on a methodical approach to optimizing the chemical deposition synthesis method for Pt-Ru/C produced from Pt(acac)₂ and Ru(acac)₃ precursors. Organo-metallic chemical vapour deposition (OMCVD) involved the precursor's vapourisation before deposition and a newly developed method which involved the precursors melting before deposition. An investigation was conducted on the effects of precursor's phase before deposition. The second investigation was that of the furnace operating temperature, followed by an exploration of the furnace operating time influence on methanol electro-oxidation, CO tolerance and catalyst stability. Lastly, the exploration of the Pt:Ru metal ratio influence was completed. It was found that the catalyst produced via the liquid phase precursor displayed traits of a high oxide content. This led to an increased activity for methanol electro-oxidation, CO tolerance and catalyst stability despite the OMCVD catalyst producing smaller particles with a higher electrochemically active surface area (ECSA).

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Stout, Sean Dakota. "DESIGN AND CHARACTERIZATION OF INTERMEDIATE TEMPERATURE SOLD OXIDE FUEL CELLS WITH A HONEYCOMB STRUCTURE; OPERATION, RESEARCH, AND OPPORTUNITIES." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1740.

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The aim of this thesis is to propose the design process and considerations to be employed in the fabrication of a high-volumetric-power-density intermediate temperature solid oxide fuel cell (IT-SOFC), as well as the necessary characterization and analysis techniques for such a device. A novel hexagonal honeycomb design will be proposed with functionally graded electrodes and an alternative electrolyte – a previously unexplored configuration based on attained research. The potential use of CFD software to investigate mass and heat transport properties of an SOFC having such a design shall be discussed, as well as the utility of experimental methods such as the generation of a polarization curve and the use of SEM to characterize electrochemical performance and microstructure, respectively. Fabrication methods shall also be evaluated, and it will be shown that the proposed design is not only feasible but meets the goal of designing an SOFC with a power density of 2 W/cm3 operating at or below 650 C.

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Xalabile, Philasande. "Development of bimetallic Pd-Zn catalysts for methanol steam reforming: hydrogen production for fuel cells." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/24325.

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Proton exchange membrane fuel cell (PEMFC) has been reported as clean and efficient energy technology from conversion of H₂. However, one of the main challenges remains the storage and transport of hydrogen. The promising alternative is to produce H₂ on site by a reformer using a H₂-dense liquid as a fuel, a technology known as fuel processing. Methanol is an attractive source of H₂ compared to other fuels as it presents several advantages, i.e. it is obtained sulphur-free, has a high H to C ratio and therefore produces a H₂-rich reformate, can be reformed at low temperatures (200 - 300°C) and is a liquid at ambient conditions so that it can be easily handled. Typically, Cu-based catalysts are used for steam reforming of methanol due to their high activity (i.e. H₂ production) and high selectivity towards CO₂. As CO poisons anodic catalyst of PEMFC, high selectivity towards CO₂ is crucial so as to eliminate or at least minimize CO removal load downstream a fuel processor. However, Cubased catalysts are thermally unstable and suffer deactivation due to sintering at high temperatures (> 250°C). Moreover, Cu-based catalysts are pyrophoric and therefore difficult to handle. Recent studies show that PdZn catalysts are very promising as they exhibit comparable activity and selectivity to Cu-based ones. Furthermore, PdZn catalysts are thermally stable in the typically methanol steam reforming temperature range (200 - 300°C). Most literature attributes high CO₂ selectivity of PdZn catalysts to formation of PdZn alloy. It is generally agreed that PdZn alloy is formed when PdZn catalysts are reduced in H₂ at high temperatures (> 250°C). In this work, a Pd/ZnO catalyst aimed at 2.5 wt% Pd was successfully prepared via incipient wetness impregnation and the duplicate preparation of the catalyst was successful. Both impregnation catalysts were confirmed by ICP-OES to contain similar weight Pd loadings i.e. 2.8 and 2.7 wt%, respectively. The actual Pd loading (ICP-OES) was slightly higher than the target loading (2.5 wt%) due to Pd content of Pd salt underestimated during catalyst preparation. Furthermore, crystallite size distribution, i.e. PdO crystallites on ZnO support, was similar (i.e. 6.7 ± 2.4 nm and 6.3 ± 1.9 nm) for both impregnation catalysts.

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aoxiang, Xiaoxiang. "Development of new proton conducting materials for intermediate temperature fuel cells." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/887.

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The work in this thesis mainly focuses on the preparation and characterization of several phosphates and solid oxide systems with the aim of developing new proton conducting materials for intermediate temperature fuel cells (ITFCs). Soft chemical methods such as sol-gel methods and conventional solid state methods were applied for the synthesis of these materials. Aluminum phosphate obtained by a solution method is single phase and belongs to one of the Al(H₂PO₄)₃ allotropies with hexagonal symmetry. The material is stable up to 200°C and decomposes into Al(PO₃)₃ at a higher temperature. The electrical conductivity of pure Al(H₂PO₄)₃ is on the order of 10⁻⁶-10⁻⁷ S/cm, very close to the value for the known proton conductors AlH₃(PO₄)₂•3H₂O and AlH₂P₃O₁₀•2H₂O. Much higher conductivity is observed for samples containing even a trace amount of excess H₃PO₄. It is likely that the conduction path gradually changes from grain interior to the surface as the acid content increases. The conductivity of Al(H₂PO₄)₃-0.5H₃PO₄ exhibited a good stability over the measured 110 hours. Although tin pyrophosphate (SnP₂O₇) has been reported to show a significantly high conductivity (~10⁻² S/cm) at 250°C in various atmospheres, we observed large discrepancies in the electrical properties of SnP₂O₇ prepared by different methods. Using an excess amount of phosphorous in the synthetic procedure generally produces SnP₂O₇ with much higher conductivity (several orders of magnitude higher) than samples with stoichiometric Sn:P ratios in their synthetic procedure. Solid state ³¹P NMR confirmed the presence of residual phosphoric acid for samples with excess starting phosphorous. Transmission Electron Microscope (TEM) confirmed an amorphous layer covered the SnP₂O₇ granules which was probably phosphoric acid or condensed phases. Thereby, it is quite likely that the high conductivity of SnP₂O₇ results mainly from the contribution of the residual acid. The conductivity of these samples exhibited a good stability over the measured 80 hours. Based on the observations for SnP₂O₇, we developed a nano core-shell structure based on BPO₄ and P₂O₅ synthesised by solid state methods. The particle size of BPO₄ using this method varied between 10-20 nm depending on the content of P₂O₅. TEM confirmed the existence of an amorphous layer that is homogeneously distributed. The composite exhibits the highest conductivity of 8.8×10⁻² S/cm at 300°C in air for 20% extra P₂O₅ and demonstrates a good stability during the whole measured 110 hours. Polytetrafluoroethylene (PTFE) was introduced into the composites in order to increase malleability for fabrication. The conductivity and mechanical strength were optimized by adjusting the PTFE and P₂O₅ content. These organic-inorganic composites demonstrate much better stability at elevated temperature (250°C) over conventional SiC-H₃PO₄-PTFE composites which are common electrolytes for phosphoric acid fuel cells (PAFCs). Fuel cells based on BPO₄-H₃PO₄-PTFE composite as the electrolyte were investigated using pure H₂ and methanol as fuels. A maximum power density of 320 mW/cm² at a voltage of 0.31 V and a maximum current density of 1.9 A/cm² at 200°C were observed for H₂/O₂ fuel cells. A maximum power density of 40 mW/cm² and maximum current of 300 mA/cm² 275°C were observed when 3M methanol was used in the cell. Phosphoric acid was also introduced into materials with internal open structures such as phosphotungstic acid (H₃PW₁₂O₄₀) and heteropolyacid salt ((NH₄)₃PW₁₂O₄₀), for the purpose of acquiring additional connections. The hybrids obtained have a cubic symmetry with enlarged unit cell volume, probably due to the incorporation of phosphoric acid into the internal structures. Solid state ³¹P NMR performed on H₃PW₁₂O₄₀-xH₃PO₄ (x = 0-3) showed additional peaks at high acid content which could not assigned to phosphorus from the starting materials, suggesting a strong interaction between H₃PW₁₂O₄₀ and H₃PO₄. The conductivity of hybrids was improved significantly compared with samples without phosphoric acid. Fourier transform infrared spectra (FT-IR) suggest the existence of large amount of hydrogen bonds (OH••••O) that may responsible for the high conductivity. A H₂/O₂ fuel cell based on H₃PW₁₂O₄₀-H₃PO₄-PTFE exhibited a peak power density of 2.7 mW/cm² at 0.3 V in ambient temperature. Solid oxide proton conductors based on yttrium doped BaZrO₃ were investigated by introducing potassium or lanthanum at the A-sites. The materials were prepared by different methods and were obtained as a single phase with space group Pm-3m (221). The unit cell of these samples is slightly smaller than the undoped one. The upper limit of solid solution formation on the A-sites for potassium is between 5 ~ 10% as introducing more K results in the occurrence of a second phase or impurities such as YSZ (yttrium stabilized zirconium). K doped Barium zirconates showed an improved water uptake capability even with 5% K doping, whereas for La doped ones, water uptake is strongly dependent on particle size and synthetic history. The conductivity of K doped BaZrO₃ was improved by a factor of two (2×10⁻³ S/cm) at 600°C compared with undoped material. Fuel cells based on Pt/Ba₀₋₉₅K₀₋₀₅Zr₀₋₈₅Y₀₋₁₁Zn₀₋₀₄O[subscript(3-δ)]/Pt under humidified 5% H₂/air conditions gave a maximum power density 7.7 mWcm⁻² at 718°C and an interfacial resistance 4 Ωcm⁻². While for La doped samples, the conductivity was comparable with undoped ones; the benefits of introducing lanthanum at A-sites may not be so obvious as deficiency of barium is one factor that leads to the diminishing conductivity.

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Menicucci, Joseph Anthony Jr. "Algal biofilms, microbial fuel cells, and implementation of state-of-the-art research into chemical and biological engineering laboratories." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/menicucci/MenicucciJ0510.pdf.

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Alternative energy technologies become more attractive as the price of energy from fossil fuels becomes more expensive and the environmental concerns from their use mount. While a number of biological alternative energy technologies currently exist, a complete understanding of these technologies has yet to be developed. This dissertation characterizes an aspect of biological alternative energy technologies: the production of algal biofuels and energy conversion in microbial fuel cells. Specifically, this dissertation addresses the characterization of microalgae as a biofilm and the characterization of the power limitations of microbial fuel cells. The attachment and detachment of algae were observed using temporal microscopic imaging in a flow-cell with autofluorescence and staining techniques as part of a collaborative Montana State University and Idaho National Laboratory project. Colonies of algae exhibit many characteristics seen in bacterial biofilms: adherence; detachment and sloughing; difference in structure of an attached colony; varying strength of attachment on different surfaces; association of other organisms in an EPS matrix; and the heterogeneous nature of attached colonies. The characterization of a microbial fuel cell was completed in less than 30 minutes using an empirical procedure to predict the maximum sustainable power that can be generated by a microbial fuel cell over a short period of time. In this procedure, the external resistance was changed incrementally, in steps of 500 ohms every 60 seconds, and the anode potential, the cathode potential, and the cell current were measured. This procedure highlights the inherent limitations of energy conversion in a microbial fuel cell. A voltage/current characterization of the microbial fuel was also completed from the data collected. This dissertation also includes the evaluation of A Hands-On Introduction to Microbial Fuel Cells, a laboratory developed for an introductory chemical and biological engineering course. The experiment has been updated to include a voltage/current characterization of the microbial fuel cell. Learning objectives have been identified and pre- and post-laboratory activities have been developed for further implementation into a chemical and biological engineering curriculum.

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Ho, Po Yu. "New molecular materials for organic and dye-sensitized solar cells and photocatalytic hydrogen generation." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/280.

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Emerging solar energy technology, including photovoltaics, solar fuels generation and solar thermal systems, is considered as one of the most potential renewable energy resources because of the tremendous and free radiant energy supply by our sun. Unlike burning of fossil fuels, carbon dioxide emission-free energy conversion process is definitely another key feature and attracting scientists to explore these research areas. Besides, this implies a giant business market to compete with traditional fossil fuel companies. Nevertheless, it is too early to realize commercial application since the technologies are in the early development stage and there is still much room to explore and improve. Simply speaking, energy conversion efficiency, robustness, environmental impacts and cost are the major factors the community should deeply concentrate on at this moment. This provides many research opportunities on the creation of novel molecular functional materials and investigates the relationship between the molecular design and functional properties, and they obviously take up significant roles in the technology evolution. The basic concepts and conspectuses regarding organic photovoltaics and light-driven hydrogen generation are collected in Chapter 1. In Chapter 2, a series of new thiophene-based small molecules is presented and the discussion is focused on its application in the bulk-heterojunction organic solar cells. Importantly, the structure-property relationship is elucidated by varying the terminal electron withdrawing group and elongating the central electron donating unit. The highest power conversion efficiency (η) of 2.6% is attained by the device with compound M3 as the active material with traditional device configuration (without any annealing process and additives addition) under AM 1.5G irradiation. In Chapter 3, a series of DπA organic dyes is introduced and the discussion concentrates on its application in the dye-sensitized solar cells. Briefly, a case study on alkyl chain effects is investigated while a new starburst triarylamine donor and uncommon selenophene-containing π-linker are studied separately. The highest power conversion efficiency (η) of 6.7% is achieved by D11 under AM 1.5G irradiation with a high open-circuit voltage of 0.825 V. In Chapter 4, three new platinum(II) diimine complexes are synthesized and they are utilized as photosensitizers with platinized titanium dioxide as catalyst site in the context of light-driven hydrogen generation. Comparison between platinum(II) diimine dithiolate complex and platinum(II) diimine bis(acetylide) complex is accomplished, and the importance of photosensitization using an organic chromophore with a desirable energy transfer consideration is accounted. Finally, Chapter 5 puts forward the concluding remarks and possible future works while Chapter 6 includes all the experimental details of the studied compounds presented in Chapter 24.

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Faria, Daniel C. "VERIFICATION AND VALIDATION OF A SAFETY SYSTEM FOR A FUEL-CELL RESEARCH FACILITY: A CASE STUDY." Ohio : Ohio University, 2007. http://www.ohiolink.edu/etd/view.cgi?ohiou1180552564.

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LARAIA, LILIAN R. "Fatores alavancadores e desafiadores no uso de mapas de rotas tecnológicas no contexto de instituições de pesquisas públicas. Um estudo de caso." reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23890.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-08-12T12:22:44Z No. of bitstreams: 0
Made available in DSpace on 2015-08-12T12:22:44Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Chidziva, Stanford. "Green hydrogen production for fuel cell applications and consumption in SAIAMC research facility." University of Western Cape, 2020. http://hdl.handle.net/11394/7859.

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Philosophiae Doctor - PhD
Today fossil fuels such as oil, coal and natural gas are providing for our ever growing energy needs. As the world’s fossil fuel reserves fast become depleted, it is vital that alternative and cleaner fuels are found. Renewable energy sources are the way of the future energy needs. A solution to the looming energy crisis can be found in the energy carrier hydrogen. Hydrogen can be produced by a number of production technologies. One hydrogen production method explored in this study is electrolysis of water.

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Qazzazie, Dureid [Verfasser], and Gerald A. [Akademischer Betreuer] Urban. "Research and development of novel hybrid nanomaterials for use as catalytic electrodes in fuel cell applications." Freiburg : Universität, 2017. http://d-nb.info/1144828961/34.

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Alsugair, Khaled A. S. "Feasibility of artificial cells in molecular sieve chromatography." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63922.

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Shukri, Ziad A. (Ziad Aziz). "Bridgman growth of CuInSe2 monocrystals for photovoltaic cell research." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40443.

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Ingots of the semiconducting compound CuInSe$ sb2$ have been grown by the Bridgman method using a single sealed quartz ampoule for both the compound synthesis, from starting elements of copper, indium and selenium, and the subsequent crystal growth. The resulting ingots, containing monocrystals of up to 2 centimeters in one dimension, were free of microcracks, voids and free of adhesion to the inner wall of the quartz ampoule. This was made possible by the unique use of a coating of boron nitride deposited on the inner wall of the ampoule prior to charging with the elements. The boron nitride acted as an effective getter in reducing the oxygen content in the starting copper, thus eliminating the adhesion between the ingot and the quartz. Reduction of the oxygen in the copper, by prior heat-treatment under high vacuum pumping, was found to be less effective than the boron nitride. The one-ampoule method used, resulted always in ingots having a uniform composition and conductivity type, which was p-type for stoichiometric starting proportions of the elements. In ingots with non-stoichiometric starting compositions, the resulting conductivity type, in the main part of the ingot, was also uniform, either p-type or n-type, with a composition close to stoichiometry. However, for non-stoichiometric melts, the last region to freeze contained binary compound phases of the elements with an excess over stoichiometry. In the main single phase chalcopyrite region, it was found that, generally speaking, n-type conductivity prevailed when the indium content was greater than about 25% and p-type when it was less than this proportion, as determined by EPMA. This was apparently irrespective of the copper or selenium content. The ingots were found to cleave, up to 1 cm$ sp2$ in area, in one of two principal cleavage planes, which are the $ {$112$ }$ and $ {$101$ }$. A third macroscopic cleavage plane, the $ {$110$ }$, was also observed in the ingots, although less frequently but wa

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Champon, Benoit. "How to regulate embryo research? : a procedural approach." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80913.

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Over the past few years, embryo research has been a widely discussed topic. New techniques such as embryo stem cell research or therapeutic cloning are considered by scientists to be very promising. Nevertheless, opponents of these experimentations warn against the commodification of human life forms and argue that the moral status of embryos should protect them from being destroyed purely for research.
Legislations on this topic have been enacted in most Western countries, though they are still much criticised. Is there an adequate way of regulating embryo research? Our argument suggests that consensus can only be procedurally obtained. That is, we believe that only legislative assemblies should have authority to take a position on this controversial topic, which is subject to moral disagreement, and as such, judges should only have a minor role.

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Hultman, Martin. "Full gas mot en (o)hållbar framtid : Förväntningar på bränsleceller och vätgas 1978 - 2005 i relation till svensk energi- och miljöpolitik." Doctoral thesis, Linköpings universitet, Tema teknik och social förändring, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-60061.

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I föreliggande avhandling undersöker Hultman hur bränsleceller och vätgas underolika tidpunkter beskrivits som delar i ett framtida energisystem 1978 – 2005. Detempiriska materialet som analyseras är statliga utredningar, böcker, rapporter,tidningsartiklar och riksdagstryck. Syftet är att undersöka vilka aktörer sombeskrev tekniken, på vilket sätt tekniken konstruerades samt hur dessa förflyttadesoch förändrades under olika tidsperioder. Avhandlingens empiri undersökstillsammans med teorier om utopier och förväntningar på teknik samt tidigareforskning om svensk energi- och miljöpolitik. Avhandlingen är indelad i kronologiskt strukturerade kapitel vilka länkas sammanav analytiska platåer. I slutkapitlet diskuteras resultaten av den historiskaförändringen från visionerna om vätgassamhällen till en vätgasekonomi i treteman. Inom det första temat analyseras omdaningar över tid med fokus påaktörer, argument och teknik. I det andra temat fokuseras hur föreställningar omtekniken byggdes upp till nya höjder mellan 2000-2005. Bland annat diskuterashur tekniska, ekonomiska, miljörelaterade och säkerhetsmässiga förväntningarskapades med hjälp av starka metaforer som vatten, vägkartan och marknaden.Dessa förväntningar gjordes på olika platser och lånades mellan lokaliteter. I dettredje temat diskuteras vätgasekonomin som en ekologiskt modern utopi. I ensådan extrapoleras framtiden utifrån en ökning i takten av teknikförändringarna,men samtidigt ska samhällsstrukturerna konserveras.
At the turn of the millennium, high expectations were connected to a technologycalled fuel cells. It was said that it could contribute in a significant way to solvingthe problem of increasing greenhouse gas concentrations in the atmosphere andreverse the greenhouse effect. But this was not the first time fuel cells andhydrogen has been described as a technology for the future and connected todifferent kind of utopias. On the contrary, this technology has a history ofexpectations connected to it and in this dissertation the period 1978 – 2005 isanalysed with focus on reoccurring arguments, main actors and how descriptionsof expectations move between different locations and different periods of time.These questions are answered with an analysis of empirical material that containsgovernmental reports, mass media articles, scientific reports as well as field notesfrom an participatory study. In this dissertation the analysis is read together withprevious research regarding Swedish energy- and environmental politics as wellas international research about fuel cell and hydrogen. The investigation is alsoinformed by theories about utopia and sociology of expectations. The main conclusion to be drawn from the historical period 1978 – 2005 is thatthe utopia hydrogen and fuel cells are said to be parts of change, from differentpossible hydrogen societies to one hydrogen economy. This change can beexemplified with changing roles of science, technology and the state as well ashow former environmental activists and political parties change their values.

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Song, Zhen-Hao, and 宋振皓. "Research on Metal Hydrogen Fuel Cells." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/3x8s4k.

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碩士
正修科技大學
電子工程研究所
107
Proton Exchange Membrane Fuel Cell is a power generation system that converts chemical energy directly into power energy. It has the advantages of high energy conversion efficiency, light in volumetric mass and low operating temperature. For a variety of small mobile power supply systems, such as electric steam locomotives, reserve power stations, mobile emergency power generation systems, etc. The density of the hydrogen storage in the hydrogen storage alloy tank is about 1,000 times that of hydrogen, which is the same as or exceeds that of liquid hydrogen. Moreover it has no danger of explosion, and the advantage of zero loss. Even it can store hydrogen for the long time and can be stored without complicated containers. High purity hydrogen is also obtained upon release, which is a safe and economical method for hydrogen storage.In this study, a lead-acid battery (full charge is 52.4V) and a PEMFC (no-load is 23.3V) constitute a battery management system (BMS). When the voltage of lead-acid batter is less than 50V, the system power is switched to the fuel cell to continue the power supply, and then the high-load voltage of the fuel cell is 22.9V. When the hydrogen storage alloy tank is replenished with hydrogen, the temperature of the hydrogen storage alloy tank will rise rapidly (up to 50°C) due to the chemical exothermic reaction of the hydrogen storage alloy tank. The half of the hydrogen storage alloy tank can be placed in the water to improve thermal dissipation, which also increase the capacity of the hydrogen storage pressure in the hydrogen storage alloy tank at the same time. The maximum hydrogen charging pressure of the hydrogen storage tank is about 35kg/cm2. In this study, the safety hydrogen storage pressure for hydrogen storage tank is about 30 kg/cm2. In the case of an empty hydrogen storage tank (0 kg/cm2), the weight of the tank is 2950g; and the hydrogen storage pressure at 30 kg/cm2, the weight of the tank is 2985g. From the measurements, it can be known that the pressure in the hydrogen storage alloy tank is 30kg/cm2,then the weight of hydrogen is 35 grams. The hydrogen storage alloy tank will be affected by certain temperature and pressure. When hydrogen is released, the hydrogen release pressure in the hydrogen storage alloy tank will decrease due to the chemical endothermic effect of the hydrogen storage alloy tank, which directly affects the operation of the fuel cell. The hydrogen storage alloy tank is thermally compensated by flowing liquid or air flow to maintain the pressure of the alloy hydrogen storage tank. The system raises the voltage of the fuel cell (23.3V) to 52V through the booster module, and reduces the voltage to 12V and 24V through the step-down module to convert the inverter to 110V and 220V AC voltage to provide our daily electrical appliances. In the case of stable operation of the hydrogen storage alloy tank, the fuel cell can be continuously operated for two hours through the supply of the hydrogen storage alloy tank

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18

Fang, Li-Hsing, and 方立行. "Research and development of Solid Oxide Fuel Cells." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/yvzr9u.

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博士
元智大學
機械工程學系
104
Fuel cell technology has attracted wide attention globally due to its high electrochemical efficiency and low emissions. Compared to the low temperature Proton Exchange Membrane Fuel Cell (PEMFC) with its high Pt catalyst cost, easy catalyst poisoning, water and heat management problems and need for extra auxiliary reforming, the high temperature Solid Oxide Fuel Cell (SOFC) has been studied more due to its higher conversion efficiency, no need for Pt catalyst, and simpler system overall. A Unitized Regenerative Solid Oxide Fuel Cell (URSOFC) is one system, which is capable of carrying out energy storage and power generation. In the electrolysis mode, it acts as Solid Oxide Electrolysis Cell (SOEC), producing hydrogen (from water). In the fuel cell mode, it acts as a Solid Oxide Fuel Cell (SOFC), generating electricity by electrochemical combination of hydrogen with air. This study addresses the fabrication of its key component– a hydrogen electrode-supported cell that uses different oxygen electrodes (LSM, LSM-YSZ and LSCF) within its operation under the SOFC and SOEC modes.

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19

Tsai, Han-Hsuch, and 蔡函學. "Research of Fault Forecasting System for Proton Exchange Membrane Fuel Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/43806614935909829171.

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碩士
國立勤益科技大學
電機工程系
99
Abstract With advancements in technology, the using of fuel cells (FCs) gradually gains commercial value due to low pollution, and many countries are actively developing FCs technologies and applications. However, during power generation of FCs, its operation may be affected by fuel purity and flow, as well as stack temperature resulting in an instable power supply. Many studies have developed FCs fault forecasting systems that can prevent operating errors leading to permanent damage. This paper has developed a FC fault forecasting system using to proton exchange membrane fuel cells (PEMFC). Firstly, a set of Zigbee wireless sensors with a PC to achieve FCs condition monitoring. The sensor modules are used to construct the data for FCs voltage, current, temperature, and supplied gas pressure. The fault forecasting system is constructed with a Labview human-machine interface, thus, users can forecast the system fault conditions, and replace the system components to prevent future risks. The system divides faults into 7 fault types, and each fault type has 13 kinds of experimental features to construct the matter-element model. Due to the time delay condition of FCs reactions, this paper first forecasted all operational features of FCs using a gray prediction model. Fault diagnosis uses the extension method and an extension neural network (ENN) to demonstrate the effectiveness of the proposed method, and compares testing results in a 200W PEMFC with other traditional methods. The experimental results confirmed that the proposed diagnostic system has a very high accuracy, fast learning, and simple structure.

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20

Ciou, Cheng-Hao, and 邱承浩. "Research of Thin Gas Diffusion Layer Manufacturing Process for Proton Exchange Membrane Fuel Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/9wd7s2.

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碩士
國立中興大學
精密工程學系所
99
Ultrathin gas diffusion layer (GDL) can significantly reduce the hydrogen fuel cell stack size. This research aims to study the ultrathin carbon fiber paper fabrication for proton exchange membrane fuel cells (PEMFCs). Polyacrylonitrile (PAN) based carbon fibers with 6 mm long was dispersed and formed at the basis weights of 15g/m2 and 20 g/m2 by a slurry molding machine. The disperse agent polyscrylamide (PAM) and polyvinyl alcohol (PVA) solutions for fiber binding were added to help carbon fibers distribution evenly and increase the paper mechanical strength. The 28x28 cm2 carbon fiber papers were completed. Since heat treatment is required to reduce carbon fiber paper electrical resistance, the phenolic resin plays the fiber binding purpose. It’s a thermosetting resin containing carbon after pyrolysis. The phenolic resin was diluted to 16 to 33% for carbon fiber papers impregnation. After impregnation, the carbon fiber papers were dried by a convective oven at temperature 120℃ for 10 minutes. After impregnating the fiber papers with different concentrations of phenolic resin, a hot press process can set down the fiber paper to the desired thickness. The hot press machine was heat to temperature160℃ and press the workpieces for 10 minutes. Two heat treatment steps were used. Low temperature heat treatment (raise the temperature to 850℃) was to carbonize the phenolic resin and bond the carbon fibers. High temperature treatment (raise the temperature to 1650℃) was to graphitize the carbon fiber and related carbon structures. After graphitization, gas diffusion substrates (GDS) in the paper form are finished. GDS then be immersed to the 5% polytetrafluoroethylene (PTFE) solution and coated with a micro porous layer (MPL), the ultrathin GDL is completed. The experimental results of this ultrathin GDLs include the thinnest thickness 48 μm, tensile strength 32~39N/cm, electrics resistance 2.5mΩ‧cm2, and gas permeability 750 cm3/cm2/s. In the Tafel test, when the cell voltage is 0.6 V, hydrogen and air gas flow ratio is 1.5/2.5, and the working temperature is 60 ℃, without the back pressure, the maximum current density is 815mA/cm2. This study shows the ultrathin GDL fabrication suitable for PEMFC applications and exhibits the feasible functionality for fuel cells.

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21

Truong, Van Men, and 張文愛. "Research of Non-Platinum Gas Diffusion Electrode Preparation for Anion Exchange Membrane Fuel Cells." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5693026%22.&searchmode=basic.

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博士
國立中興大學
精密工程學系所
107
This research focused on the preparation of non-platinum electrodes applied for anion exchange membrane fuel cells (AEMFCs). Specifically, two attempts including the development of silver nanoparticles supported on functionalized carbon particles (Ag/C) used as the cathode catalyst in AEMFCs and the study of the effects of PTFE content in gas diffusion substrate, microporous layer, cell temperature and inlet gas humidification on AEMFC performance were carried out. The characterization results show that Ag/C catalyst was successfully synthesized by wet impregnation method. For AEMFC performance evaluation, the experimental results showed that the peak power densities of the single AEMFC using Ag/C were only 3.5% lower than that using commercial Pt/C which was consistent with the cyclic voltammetry (CV) and linear sweep voltammetry (LSV) measurements. Therefore, the Ag/C can be used as the cathode catalyst to substitute the commercial Pt/C as the strategic cost reduction, so that a commercialized alkaline anion exchange membrane fuel cell can be realized. Moreover, the gas diffusion substrate (GDS) treated with polytetrafluoroethylene (PTFE) can offer not only an appropriate hydrophobic level but also robust supporting for the microporous layer and catalyst layer. Thereby, well water management and catalyst usage in the cell can be obtained during the cell operation. The testing results showed that the best cell performance was achieved by employing the GDS with 30 wt.% PTFE content and MPL at both anode and cathode sides of a single AEMFC. Although PTFE treatment in the GDS is beneficial for AEMFC performance, excessive PTFE embedment in the GDS will lead to an adverse effect due to most of the pores on the GDS surface blocked by excessive PTFE particles, causing a severe hindrance of transport of reactant gas and water. In addition, it is found that the AEMFC performance was strongly affected by the cell operating temperature and highly sensitive to humidification at both anode and cathode inlet gases. Besides, back diffusion could partly support the water demand at the cathode once the water concentration gradient between the anode and cathode is formed. These results suggest that the water management in AEMFCs plays a critical role in achieving a desirable cell performance.

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22

Wang, Jhang-Han, and 王章翰. "Research of Polyethyleneimine Modified Carbon Cloth Anode Electrodes for Self-Pumping Glucose Oxidase Fuel Cells." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/36625021527359458220.

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碩士
國立中興大學
精密工程學系所
104
The polyethyleneimine (PEI) to modify carbon cloth electrode for reducing processing time and increasing self-pumping glucose oxidase fuel cell electricity was studied. Because enzyme should be well attached on the electrode, a high compatibility support is needed. PEI is usually used in gene transfection of biochemical engineering utilized as support of Glucose Oxidase (GOx) to enhance the enzyme immobilization, it is a good candidate to increase redox current for enzymatic fuel cells (EFCs). PEI and GOx had been successfully immobilized on carbon cloth electrode through FT-IR analysis, then UV / Vis spectrophotometer was used to investigate the best concentration of PEI support. The PEI was proved to be the support that improved redox current by cyclic voltammetry analysis. The modified carbon cloth electrodes were assembled into an EFC single cell. The self-pumping fluid enzymatic fuel cell results showed that 4 wt% PEI of GOx carbon cloth electrode can achieve at 0.48 V with the maximum power density 0.609 mW cm-2(126.9 mW cm-3). The experimental results showed the practical use of PEI as the support for GOx in EFCs.

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23

Lai, Chao-Wei, and 賴晁偉. "Research of Buckypaper Characteristics Processing for Proton Exchange Membrane Fuel Cells Gas Diffusion Layer Characteristics." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/41510529397994468628.

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碩士
國立中興大學
精密工程學系所
102
This research aims to study the buckypaper fabrication and characteristics processing for gas diffusion layer (GDL). Mixed acid (HNO3/H2SO4=1/3) is refluxed for 40 min. Cationic surfactant hexadecyl trimethyl ammonium bromide (HTAB) is modified by carbon tubes. Multiwall Carbon Nanotubes(MWCNT) is dispersed and formed at the basis weights of 1.45 to 3.3 mg/cm2 by a slurry molding machine. The disperse agent DI water and polyvinyl alcohol (PVA) solutions are added to MWCNT. And then MWCNT it''s distribution is evenly and mechanical strength of paper is increased. The buckypaper were completed by vacuum filtration technology. The phenolic resin is diluted to 10 to 30% for impregnation of buckypaper. After impregnation, the buckypaper were dried by a hot plane at temperature 160℃ for 10 minutes. The hot press machine was heated to 160℃ and pressing the workpieces for 10 minutes. After hot press, carbon nanotube is graphitized to improve the structures of carbon by high temperature treatment (raising to 1600℃). And then the buckypaper is immersed to polytetrafluoroethylene (PTFE) solution that is diluted 10 to 20%. The ultrathin GDL is completed by Above-mentioned process. The experimental results include the thinnest thickness that is 38 μm and electrical resistance that is 3.7 mΩ‧cm and water contact angle that is 121˚.

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24

Huang, Li-Zhen, and 黃俐禎. "Cross-Linking Agent Modified Anode Electrodes for the Research of Self-Pumping Glucose Oxidase Fuel Cells." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/wqe33s.

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碩士
國立中興大學
精密工程學系所
106
A self-pumping glucose oxidase enzymatic fuel cell (GEFC) with a new anodic catalyst which was modified by coating three different cross-linking agents such as TPA, GA, and TPP to form CNT-CC/[PEI/(GOx/TPA)], CNT-CC/[PEI/(GOx/TPP)] and CNT-CC/[PEI/(GOx/GA)] anode electrode, was fabricated, respectively. By using of these reagents as the chemical bonding method for enzyme immobilization, the amount of enzyme immobilized on the electrode and the enzyme stability are enhanced as well as improve the electrochemical performance of the self-pumping GEFC. To test the ability of GOx enzyme immobilized on the modified electrode and its chemical structure, the SEMs and the FTIR were successfully accomplished. In addition, the UV/Visible spectrophotometer was used in order to analyze the enzyme activities of the electrodes. New anodic electrodes (CNT-CC/[PEI/(GOx/TPA)], CNT-CC/[PEI/(GOx/TPP)] and CNT-CC/[PEI/(GOx/GA)]) affect the electrochemical performance of the self-pumping GEFC, were measured from the redox reaction current peak by CV curves. Moreover, the self-pumping GEFC performance test, results showed that the maximum power density of the cell with CNT-CC/[PEI/(GOx/TPA)] which is approximately 11% higher than that of the cell with CNT-CC/[PEI/(GOx/TPP)] and CNT-CC/[PEI/(GOx/GA)] (0.88 and 0.87 mW.cm-2, respectively) and 61% improvement compared to our previous research without adding the cross-linking agent (0.609 mW.cm-2) is 0.98 mW.cm-2. Finally, with a fixed volume of fuel supplied into the anode side, the output power density of the self-pumping GEBC was continuously measured for lasting 30min.

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25

Menicucci, Joseph Anthony. "Algal biofilms, microbial fuel cells, and implementation of state-of-the-art research into chemical and biological engineering laboratories." 2010. http://etd.lib.montana.edu/etd/2010/menicucci/MenicucciJ0510.pdf.

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26

Tseng, Chun Ch''i, and 曾駿騏. "Research of the Phosphoric Acid Content in Membrane Electrode Assembly of ABPBI-based High Temperature PEM Fuel Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/47187268019201988988.

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碩士
元智大學
機械工程學系
99
In this study, the conductivities of commercial AB-PBI membranes doped with 85 wt% H3PO4 as well as different bathing timings and temperature are investigated. Also, the electrodes including AB-PBI polymer and Pt/C catalyst are investigated with different H3PO4 loading. The as-prepared electrodes and membranes are combined to manufacture membrane electrode assembly for high temperature proton exchange membrane fuel cell(HT-PEMFC) application. Effects of H3PO4 contents in membranes and electrodes are studied with material properties as well as fuel cell performance. The results reveal that AB-PBI membranes doped with 85 wt% H3PO4 at bathing temperature of 90 ℃ for nine hours lasting has highest conductivity 33 mS/cm. The membrane with highest conductivity is selected and combined with electrodes including 15 wt % AB-PBI and 0.75 mg/cm2 Pt loading. The current density, 260 mA/cm2 , of the as-prepared MEA at 0.6 V and 160℃ using oxygen and hydrogen as inlet is highest compared with other samples. Characterization of the electrodes before/after constant current 200 mA/cm2 discharging using I-V curves, AC impedances, and CV, to study voltage change with time of different H3PO4 loading.

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27

Chan, Pin-Cheng, and 詹彬程. "A novel research of local diagnosis of temperature, voltage, and flow rate in fuel cells by integrated micro sensors." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/45401701254994036627.

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碩士
元智大學
機械工程學系
98
The temperature in membrane electrode assembly (MEA), voltage distribution and fuel operating conditions in flow channel significantly contribute to fuel cell performance. The conventional methods can not determine the accurate of inner change. This work presents flexible and multi-functional micro sensors that decrease the insulating area and effect on fuel cells. By using micro-electro-mechanical systems (MEMS) for novel applications and innovative fabrication integrated with micro flexible temperature, voltage and flow sensor, this work integrates the three separate functions of a flexible micro temperature, voltage and flow sensor into one. Through using stainless steel foil (40μm) as a flexible substrate, it is so sufficiently small as to place anywhere between MEA and flow channel, and the additional design for support frame is unnecessary. Therefore, the micro sensors integrated into the fuel cell have the merits of multi-function, high accuracy, high linearity, high sensitivity, extreme flexibility, mass production and short response time. Integrated micro sensors are embedded in a fuel cell to determine the temperature, voltage and flow parameters in the inner flow channel of a fuel cell. Users can command and monitor the temperature status, voltage distribution and fuel operating condition in a flow channel of a fuel cell. The operating parameter is then adjusted to increase both fuel cell performance and service life.

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28

Aliahmad, Nojan. "Paper-based lithium-Ion batteries using carbon nanotube-coated wood microfiber current collectors." Thesis, 2013. http://hdl.handle.net/1805/3652.

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Indiana University-Purdue University Indianapolis (IUPUI)
The prevalent applications of energy storage devices have incited wide-spread efforts on production of thin, flexible, and light-weight lithium-ion batteries. In this work, lithium-ion batteries using novel flexible paper-based current collectors have been developed. The paper-based current collectors were fabricated from carbon nanotube (CNT)-coated wood microfibers (CNT-microfiber paper). This thesis presents the fabrication of the CNT-microfiber paper using wood microfibers, coating electrode materials, design and assemblies of battery, testing methodologies, and experimental results and analyses. Wood microfibers were coated with carbon nanotubes and poly(3,4-ethylenedioxythiophene) (PEDOT) through an electrostatic layer-by-layer nanoassembely process and formed into a sheet, CNT-microfiber paper. The CNT loading of the fabricated paper was measured 10.1 μg/cm2 subsequently considered. Electrode material solutions were spray-coated on the CNT-microfiber paper to produce electrodes for the half and full-cell devices. The CNT current collector consists of a network structure of cellulose microfibers at the micro-scale, with micro-pores filled with the applied conductive electrode materials reducing the overall internal resistance for the cell. A bending test revealed that the paper-based electrodes, compared to metal ones, incurred fewer damages after 20 bends at an angle of 300o. The surface fractures on the paper-based electrodes were shallow and contained than metallic-based electrodes. The micro-pores in CNT-microfiber paper structure provides better adherence to the active material layer to the substrate and inhibits detachment while bending. Half-cells and full-cells using lithium cobalt oxide (LCO), lithium titanium oxide (LTO), and lithium magnesium oxide (LMO) were fabricated and tested. Coin cell assembly and liquid electrolyte was used. The capacities of half-cells were measured 150 mAh/g with LCO, 158 mAh/g with LTO, and 130 mAh/g with LMO. The capacity of the LTO/LCO full-cell also was measured 126 mAh/g at C/5 rate. The columbic efficiency of the LTO/LCO full-cell was measured 84% for the first charging cycle that increased to 96% after second cycle. The self-discharge test of the full-cell after charging to 2.7 V at C/5 current rate is showed a stable 2 V after 90 hours. The capacities of the developed batteries at lower currents are comparable to the metallic electrode-based devices, however, the capacities were observed to drop at higher currents. This makes the developed paper-based batteries more suitable for low current applications, such as, RFID tags, flexible electronics, bioassays, and displays. The capacities of the batteries at higher current can be improved by enhancing the conductivity of the fibers, which is identified as the future work. Furthermore, fabrication of an all solid state battery using solid electrolyte is also identified as the future work of this project.

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29

TI, TSENG WEN, and 曾文毅. "Research of Alkaline Fuel Cell." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/01706188106316336033.

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碩士
大葉大學
機械工程研究所碩士班
94
Various kinds of relevant packages, such as bipolar plate, a board channel, catalyst of the alkaline fuel cell are complicated and expensive, if we can research and develop the new-type alkaline fuel cell. The catalyst, reduce and make the threshold, can make the cost reduce effectively. Use the metal and plastics to utilize metal and plastic processing easy, cheap and anticorrosive characteristic as the main material of fuel cell in the experiment, it is due to its merits of low cost, good corrosion resistance, efficient heat transfer good electrical conductivity, and being robust compact, as well as lightweight. so to have, different from over the alkaline fuel cell on this research , develop out the new form for the alkaline fuel cell. This research use metal network to electroplates catalysts , fix the electrode in the gas and liquid mixing area and utilize the stainless steel network , carbon cloth and Renee nickel, electroplate various kinds of catalysts , carries on the relevant experiment to test, will test the data analysis , will probe into the impact on alkaline fuel cell of catalyst, come to verify this alkaline fuel cell superiority and practicability by this. The result of study shows: Apply the catalyst on many hole materials, its bending and material is processed degree more than superior to the tradition with the fuel cell of the carbon cloth (paper), but Renee nickel hole easy to brake of bending. We can know via the single fuel cell relevant experiment, the single fuel cell power can increase the electric current amount via the way to pile pile, make the fuel cell catalyst increase three-dimensional space by the ordinary coating, to really pile pile and become intact three-dimensional space, if can study several, such as follow-up porous material, durability,etc. There will be very great benefitting to the development of the technology of the fuel cell.

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30

Yung, Yang Ching, and 楊情勇. "Fuel Cell Patent Map Analysis and Research." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/95968843368596598363.

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碩士
中華科技大學
機電光工程研究所在職專班
99
As the world's energy in critical shortages, mean while nuclear energy is no longer the safe development solution, industrial countries are all actively studying the new reliable power. Although wind, tidal and solar energy is widely used as alternative power, different type powers are more often limited to industrial or household use. For the typical vehicles and transportations, these three energy’s scale is too big to fit in, so all are not suitable for passenger traffic. Instead, the use of "Fuel Cell" mainly caused by the sizes effect, product flexibility, cost consideration and other application factors. In the objective conditions, vendors of emerging energy, on such technological requirements and specifications, have not been reunified. When the current technology and processes have been approved, the “Fuel Cell” is the trend of long term energy utilization. Expected by this research , "Fuel Cells" is the core technology and presents a lot of patents, so that consumers have knowledge of fuel cell reliability and economy, through a variety of patent terms, researches. For innovative manufacturing, fuel cell could be updated by the layout and patent applications. So the application strategy or the choice of royalty payments may be decided earlier before jump into the crucial market. The research process is normally set as: firstly the fuel cell based technologies, products dismantling, the hydrogen battery technology, and related components. Mainly the fish bone diagram and tech tree diagram are used to clarify the important technical documents or papers which related to the timing and key points. From the prior patent documents, the purpose is to distinguish important techniques, components and related derivatives. And even on the same battery technology, it could figure out some similarities and differences. The use of preliminary data compilation and the summary of retrieving patent documents, as cut into the core of research papers, prepare for a complete review. Typically, the literature research process which can be distinguished weather the browse work is completed or not, where the new area of research is yet plenty of room for improvement of the missing patent and to avoid the pitfalls. In this study, patent search is made by specific choice, technical component classification, retrieval of relevant patent of fuel cells, inventors, applicants, and son on. The first preliminary analysis of the relevant patents includes patent category, patent classification, and patent inventor during the patent execution. Then, referred to the patent literature on the layout pattern of fuel cell technology, as the patent strategy, the patent portfolio model features the patents to identify specific patterns and become the competitive strategy. Further, to read the core patent will abstract the purpose of each patent and protect the benefit subject to achieve the business goals. Also, the effectiveness of technical means and description assign the technical details such as the original classification. The most important method is that the patented technology can be characterized according to their nature approaches and described the conceptual framework or technology description. The trend is divided into source-based, sub-source, and application-oriented patents. Finally, the research from the patent and the its covers areas, such as strategic direction of the layout of patent, will restore or deconstruct the fuel cell products into the patent application strategy or planning. In providing enterprises with a highly commercial value and innovative products, our research applies strategies, patent portfolio and risk assessment with the references to the evaluation of planning. Keyword: fuel cell、fuel cells、fuel battery、fuel batteries

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31

Hsieh, Yi-hung, and 謝宜宏. "Research on Solid Oxide Fuel Cell Sealing." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/14920723050490773669.

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碩士
國立臺灣科技大學
機械工程系
96
In solid oxide fuel cell (SOFC) studies, sealing is an important issue. It can be generally categorized into rigid bonded seals and compressive seals in the literature. Rigid bonded seals have better sealing performance, but sealing materials are limited and maintenance is difficult. Compressive seals can resolve above issues, but its performance depends on the applied pressure and cell specimens may damage if over-pressurized. The purpose of this research is to obtain suitable compressive seals structure and sealing materials. In this research, compressive seal structure of the single cell utilized stainless steel (AISI 304) and Mica as sealing materials. In order to evaluate the sealing performance of each material, simplified test models were first adopted respectively. In stainless steel seals, the most suitable gap size (Gap A) and compressive pressure (9.8kN) were determined by experiments. Simulating the gas flow in a single-cell, the leakage rates of the flow at different temperatures were measured. The fuel gas was 5% H2 and the flow rate was set to be 100 sccm. Both sealing materials had fewer leakage rate at 800℃—1% for stainless steel and 2% for Mica. Moreover, three thermal cycles were tested and the sealing performances were preserved. In the single-cell test, using Ni-YSZ/YSZ/Pt-YSZ specimens, the cell was sealed with the combination of stainless steel and mica at different locations. When the flow rate of 5% H2 fuel gas was 100 sccm, the better leakage rate of 3% occurred at 800℃ with the best power density of 58.86 mW/cm2. If gas changed to 15%, the best power density was 66.22 mW/cm2 at 800 ℃. Compared with the literature, the seal structure designed in this research can effectively enhance SOFC power generation efficiency. Finally, based on the single-cell sealing concept, a preliminary design of 3-cell stacks was proposed.

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32

唐逸平. "A Research on Micro Fuel Cell Technology." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/30123950503492165757.

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碩士
國立交通大學
科技管理研究所
94
Fuel Cells are one of the most promising technologies for the power source of the future. The fuel cell is an electrochemical device that converts energy into electricity and heat without combustion. It is different from a battery in that it does not release energy stored in the cell. Instead the energy is converted from a hydrogen laden fuel directly into electricity. The use of fuel cells in its cleanest state does not emit pollutants. Micro fuel cells are being developed as a result of a growing need to power a wide range of very powerful devices such as: personal communications devices, portable computers, personal data assistants, consumer products, digital cameras and so on. Presently, there is a shift taking place in the secondary battery market [4]. Lithium ion batteries are gaining significant market share over older nickel based chemistries, however even this technology is starting to approach its theoretical limits. Because fuel cells have a higher specific energy density than conventional batteries, they are expected to penetrate the growing portable power supply market as rapidly as lithium ion chemistry has done with secondary batteries [5]. The primary purpose of this paper is to research the developments of micro fuel cells and analyze drivers and constraints of the industry. This paper will explore the patent research method as a source for primary data in technology innovation. The research will include a search of the United States Patent and Trademark Office (USPTO) in order to obtain primary information on the micro fuel cell sector. Further research into secondary sources will be used to supplement the primary information.

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33

Chiou, Chau-Juan, and 邱朝專. "Research of metal bipolar plate fuel cell stack." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/55647427258824340240.

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碩士
國立中興大學
精密工程學系所
98
The purpose of this current study is to assemble a low-temperature operating fuel cell stack whose metal bipolar plates are made of aluminum and flow channels on the metal bipolar plates are created by CNC. The flow channels on the bipolar plates are 2 mm high and 2mm wide. The metal bipolar plates are plated with corrosion-resistant metal, within 10μm, by electroless plating. In addition to the metal bipolar plates, low thermal conductivity of bakelite as side boards, allowing the air in and out, and MEA whose response area is 5×5cm2 are used to assemble a PEMFC (Proton Exchange Membrane Fuel Cell). This study successful assembled the metal bipolar plate fuel cell stack with a maximum power density of 4933.6mW/cm2 and a maximum current density of 620mA/cm2. The performance of the cell stack assembled in this study is stable and consistent, achieving the purpose of developing renewable energy which can be sustained forever. Key words: flow channel design, metal bipolar plate, PEMFC, electroless plating

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Liu, Pan-Hsiu, and 劉本修. "The research of fuel cell hydrogen supply control." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/99685873119694952980.

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碩士
國立中央大學
光機電工程研究所
100
In recent years, the concept of energy conservation and carbon reduction is noticed by people. Fuel cell is a clean energy, it only need hydrogen and oxygen to generate energy, and only produce water. However, hydrogen is not easy to obtain, therefore how the hydrogen reaction in the most efficient way would be the most important issue. It has two ways to use hydrogen in efficient way; the first one is change inside of fuel cell to improve the efficiency of chemical reactions, the second one is control the hydrogen to get high efficiency use of hydrogen. This thesis is using the second way, the use of on-off valve to open hydrogen, let constant flow into the fuel cell flow field plate, the excess unreacted hydrogen will be full of the fuel cell flow field plate, to detect the rapid decline current in the hydrogen is exhausted, and open the on-off valve, the hydrogen flow into fuel cell until full of the flow field plate. When the current rapid decline because of fuel cell internal hydrocephalus, open the on-off valve to purge the fuel cell. This thesis use ARM chip as a controller, and use Microsoft Visual Basic(VB) to write the interface between controller and computer, using RS-232 communication interface to communicate with the ARM chip, and display the value of current and voltage on the computer screen, in order to record and analysis.

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35

Wu, Yao Tso, and 吳曜佐. "Research and development of zinc air fuel cell battery." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/43861431866422830352.

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碩士
國立屏東科技大學
車輛工程系所
100
The purpose of this research is development of zinc air fuel cell battery. First, the cell marking is the key point in development process, and that is mainly to establish the excellent manufacture parameters of anode, cathode and electrolyte by experimental analyses in cell performance. There are series of works are provided including single cell design, cells assembly design, performance analysis. The open current voltage test, long term constant voltage discharge test, long term constant watt discharge test, continuity supply anode fuel discharge test, and continuity fill electrolyte discharge test of the single cell performance of were measured. Finally, set up the ZAFC modules and test in this study. According to the test, the better performance of zinc anode is when pressure and temperature are controlled in the 200 kg/cm2, 350 ℃. The best PTFE ratio of the diffusion layer is 40% and catalyst layer is between 10 to 20 %. Single cell discharge performance is 90 Wh / kg. Module discharge test is up to 18 hours, and the module performance is 103 Wh / kg. The repeated discharge test in five times, the working time is up to 10 hours or more.The module series test, working time is up to 17 hours.

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Hsu, Chien-Pin, and 許建彬. "Research on catalyst dispersion in paste of fuel cell." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/86628599436192798329.

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碩士
國防大學中正理工學院
應用化學研究所
95
The fuel cell is known as the fourth generation of technology of generating electricity after generating electricity in fire power, wind-force and nuclear energy, it possesses low polluting, high efficiency and characteristic that can long run , and become the new energy technology which various countries of U.S.A., Europe, Japan fall over each other to develop and popularize in recent years. Exchange the membrane fuel cell as the foundation with the proton, use the methyl alcohol as the direct methyl alcohol fuel cell of the fuel is the mainstream that the miniature fuel cell is developed. Direct methyl alcohol fuel cell can not be commercial because of low discharge power and material cost too high, the electrode uses the noble metal catalyst to improve catalyst service efficiency, not only can increase the power of discharging of the membrane electrode group, will reduce the material cost too. Improvement, catalyst of service efficiency it depends on to be appropriate to control hole degree, hydrophile, polymer disperse and distribution on electrode. Outside dispersing the catalyst in this paper divided by proper mixing way, and then choose the suitable dispersant to make the paste steady, and can reduce its influence on the catalyst activation .The dispersion of catalyst paste is analyzed with laser scattering, rheometer. Assemble into an electrode and carry on CV efficiency to analyze finally, the efficiency and life-span that probe into it and discharge. In this research, the planet mixer was the best physical dispersal procedures. By the planet mixer, the particle size of catalyst was below 400 nm. In chemical dispersion method, the dispersant SA was the most less influence on catalyst activity, and the particle size was about 250 nm and zeta potential was -48 mV. Finally, the result of single cell measurement, we can reduce catalyst content in paste of fuel cell and improve the performance of single cell. Key word: Direct methanol fuel cell, Membrane electrode assembly, Rheometer

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YU, Lin Tung, and 林淙裕. "The Research of Digitization Control for Fuel Cell Energy System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68252720092257124918.

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碩士
大葉大學
電機工程學系
96
This thesis is to research the conversion of energy and the control system of the fuel cell by using Digital Signal Processor (TMS320F2407A) which can monitor and control the signal system performance. During the experiments, the power is supplied by Proton Exchange Membrane Fuel Cell (PEMFC). The push-pull converter will boost the voltage via the full-bridge inverter with the low pass filter to transfer the DC voltage to AC 110 V. In order to obtain the stable output voltage and current, the pulse width modulation control signals are generated by Digital Signal Processor (DSP) chip, according to the feedback current.

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38

Tsai, Yun-Fang, and 蔡昀芳. "Research of Self-Pumping Fluid Glucose Oxidase Enzymatic Fuel Cell." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/40780749406889348350.

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碩士
國立中興大學
精密工程學系所
102
A self-pumping fluid glucose oxidase enzymatic fuel cell was designed and fabricated. Fuel was driven into the fuel cell by capillary effect without any external pump. Fuel cell structure design included both end plate and flow channel plate. Three reservoirs are fabricated onto the end plate. And Cotton cloth was placed into the reservoirs. A particular flow channel was designed to obtain a uniform parallel flow field. The cross sectional area was decreased from central channel to inlet and outlet channel. The flow channel plate was fabricated by electroforming and lithography. And the flow field hydrophilic modification was carried out to boost capillary effect. According to the experimental analysis, the cathode and anode flow rate were less than ideal flow rate. Anode and cathode flow rate were 0.499 μl s-1 and 0.764 μl s-1 respectively. And the capillary driven liquid efficiency of anode and cathode flow field was 36 % and 53 % respectively. The result of Tafel test for self-pumping fluid enzymatic fuel cell showing a power output of p = 0.534 mW cm-2 (111.217 mW cm-3) was achieved. Furthermore, the current output performance of long term experiments at a constant voltage of 0.42V indicated that the self-pumping fluid enzymatic fuel cell may work stably under a continuous fuel supply.

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39

Pou-Yu, Chiang. "The research is to evaluate the fuel cell in millitary benefits and the concept design of fuel cell hummv." 2000. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0009-0112200611342823.

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40

Chiang, Pou-Yu, and 蔣伯餘. "The research is to evaluate the fuel cell in millitary benefits and the concept design of fuel cell hummv." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/91590587721333675549.

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碩士
元智大學
機械工程研究所
88
ABSTRACT The fuel cell is a welcomed technique of generated electric power. Because of its quality such as low noise, super low radiant heat, low pollution and high efficiency, so that it can be applied in the military affairs. Furthermore there''s military benefits i.e. to maintain the electric power system of command, management, communication and intelligence, after the attacked by China. The research is to evaluate the fuel cell in military benefits and the concept design of fuel cell hummv . There are five directions of evaluation for military benefits: 1. War preparedness: to evaluate the electric power supply, 2. Barrock: to evaluate energy benefits of electric power supply system, 3. Usage of transportation: to evaluate the decreased quantity of air pollution, 4. Combat vehicles: to evaluate the air decreased quantity of greenhouse effect and 5. Combat vehicles: to build up its noise index data. The concept design of fuel cell hummv is considered and designed in parts of military tactics and economics. The results are as follows: 1. Average discharged coefficients of hummv are HC=1.027469 (g/km), CO=5.260434 (g/km) and CO2=781.3882776 (g/km). 2. Fuel cell vehicle is found nearly 15 meters by enemy, diesel vehicle for transportation (10.5 tons) is found nearly 70 meters by enemy and the present used vehicle M60A3 and hummv in the military are found far more than 200 meters by enemy. 3. If the set up cost of fuel cell can be added till USD35/KW, no matter for its set up cost or operation cost, the fuel cell can have its excellent superiority. 4. Change the present hummv to fuel cell vehicle, this changing system will not add up the volume of the present hummv and the combat efficiency can be enhanced as well.

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41

Li, Bo-wei, and 李柏緯. "Research for full printing process for polymer organic solar cells." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/71143900268906520386.

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碩士
國立中正大學
機械工程所
98
The development of fabrication of organic solar cells today, which is still using spin coating process for small-scale devices in laboratory, or evaporating will increase the cost and cannot producing for large-scale by limits of the vacuum chamber. In this thesis, the spin coating and evaporating is replaced by micro-contact printing process for fabricating bulk-heterojunction organic solar cells. Printing the high-polar polymer of hole transport layer by atmosphere plasma treatment under ambient conditions. For reproducing the spin coating results for thickness, roughness and absorption spectroscopy of polymer active layer thin film by printing process. The solubility and concentration of polymer solution is increasing by mixed solvents. And the research of printing gel-type silver electrode with patterns. We discuss the feasibility of stacking each layers of device by adhesion work’s theory in following. Then the micro-contact printing and prewetting technique are used to stack the materials layer by layer at room-temperature without high pressure. The fabrication of polymer organic solar cells is accomplished by full-printing process. And we have characterization of the conventional or inverted devices which are fabricated with electron or hole transport as buffer layers by solution process.

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42

Liao, Yuan-kai, and 廖元楷. "Research of gas diffusion layer on polymer electrolyte membrane fuel cell." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/73664089301487084955.

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博士
逢甲大學
材料科學所
97
The constituents of a polymer electrolyte membrane (PEM) fuel cell are graphite bipolar plates, gas diffusion layers, catalyst layers and a proton exchange membrane. The main gas diffusion layer serve mainly as an electronic conduction medium, a fuel transmission pipeline and a catalyst backing material. In first research, a carbonization process is used to make gas diffusion layers (GDL) of polymer electrolyte membrane fuel cell (PEMFC) from polyacrylonitrile (PAN) carbon fiber cloths The results showed that the electrical resistivity decreased at higher heat-treatment temperature and Lc get larger, while d002 became smaller. The carbon fiber cloths with higher heat-treatment temperature showed better performance. With two manufacture types of PAN carbon fiber cloths showed the limited current density of 1358 mA/cm2 and 1337 mA/cm2 at heat-treatment temperature of 1500 ℃, respectively. Second and third parts of studies use different carbon fiber reinforcing materials impregnated with different phenolic resin concentrations to produce composite materials for use as fuel cell gas diffusion layer (GDL) substrates. Due to the differing structures of various carbon fiber reinforcing materials, GDL substrates made from these materials display different characteristics. For instance, GDL substrates produced from oxidized carbon felt have a relatively loose structure and can absorb a large quantity of resin; the properties of this type of substrate may change significantly with resin content. In contrast, the weave structure of oxidized carbon cloth tends to lessen the influence of the impregnated resin content. With regard to fuel cell performance, GDL substrates fabricated from oxidized fiber felt yield the best performance when resin content is 10 wt%, and have a limiting current density of as high as 1677 mA/cm2. A resin content of 2 wt% yields optimal performance when oxidized carbon cloth is the raw material, and the limiting current density can achieve 2207 mA/cm2.

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43

Yang, Chih-Wei, and 楊致瑋. "Research of catalyst support in Alkaline Anion Exchange Membrane Fuel Cell." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/17038993740943733271.

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碩士
國立中興大學
精密工程學系所
104
This study aims to use two kinds of carbon materials, multi-wall carbon nanotube and carbon black as catalyst supports and combine with phthalocyanine cobalt through 800℃ high temperature treatment to produce a cathode catalyst for Anion Exchange Membrane Fuel Cell. The MN4 macrocycles, phthalocyanine cobalt can be combined with the catalyst support through high temperature treatment. The catalyst CoPc/MWCNTs and CoPc/CB can form different ratios, 20%, 30%, 40%, 50%, 60%, 70% respectively. The surface analysis was done by XRD and SEM to confirm the combination of catalyst and support successfully. The Cyclic Voltammetry was done to investigate the trend of the best ratio, then, the MEA (Membrane electrode assemble) was fabricated to do the fuel cell test. Both catalyst got the best power density in the ratio of 40%, and the best power density was produced by CoPc/CB which produced 55mW/cm2, in 0.4V. The promising catalyst CoPc/MWCNTs produced only 35 mW/cm2, which did not meet the expectation, according to the references, the alkaline fuel cell performance might be bothered by the acid residues, sulfates and nitrates which produced by the purification process of MWCNTs.

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44

Yang, Chieh-Jen, and 楊介仁. "The Research of Hybrid Power Systems Applied in Fuel Cell Vehicles." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/97468871413671717920.

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碩士
國立高雄應用科技大學
應用工程科學研究所
98
This research presents the design and analysis of hybrid power sources, i.e., a combination of a proton exchange membrane fuel cell and a secondary battery, as applied in fuel cell vehicles. The candidate for the secondary battery is chosen based on its cost, weight and power efficiency. An analysis is then carried out on the strategies of designing a hybrid power source based on the compensative characteristics between the PEM fuel cell and the secondary battery as used in static-state and actual road tests of a fuel cell vehicle. In order to compensate an inefficient dynamic response of the fuel cell and to further utilize its power, this study proposes three hybrid systems to be analyzed: a parallel type, an independent type, and an auxiliary-parallel type. The experimental results show that the control mode of the auxiliary-parallel type yields an optimal performance, e.g., a cruise distance of 2.92 km with an average power of 104.8 W for every gram of hydrogen consumed under a constant operational current of 4 A. It is thus concluded that the auxiliary type and the parallel type should be used respectively for medium and high current demands.

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45

Hung, Hsu Chien, and 許建鴻. "Research of the warship dynamical propulsion AIP system from fuel cell technology." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/53865315469659938232.

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碩士
國防大學中正理工學院
造船工程研究所
93
The air independent propulsion system makes the routine possess the submerge ability for a long time like sneaking the nuclear power definitely warship, The major advantages of AIP collocate proton exchange membrane fuel cell system are：high energy density , low temperature operate , oxygen consumption low and to reduce noise. Then, in this study, the PEMFC is the target of study. In numerical simulation, adopt CDF-RC software, first under 0.6 V situations to operate the voltage, consider activation polarization, ohm polarization and concentration polarzation three losses, to relative humidity, porosity and aspect ratio to act as the discussion. The parameter effect of aspect ratio is better than relative humidity and porosity. Secondly, only consider the effect of the activation polarization in operate the density 150 Amp/m2 of the electric current cases, to discussion that such parameter effects as the relative humidity and porosity, its result is relatively close to the ideal battery characteristic curve. Synthesize result the above, CFD-RC in operate software electric current under the density 150 Amp/m2, than operate accuracy its voltage 0.6V high.

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46

HSUEH, CHEH-YEN, and 薛俊彥. "Design Research of Electrical Scooter for Environmental Protection Under Fuel Cell Energy." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/08627557771467430397.

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碩士
大葉大學
設計研究所
94
Promoting environmental proection electric scooters can significantly reduce the pollution that transportation vehicles bring to the environment. While the whole world is working full-speed to carry out such plan, it is vital for Taiwan to use its strong development in the motorcycle industry as a base for commercializing the fuel cell scooters. The fuel cell system is simply the power sector of electronic scooters. In order for such competitive, environmental proection energy to be accepted and widely used by the general public, fuel cell motorcycles need a comprehensive and innovative design to join the consumer market quickly. This research institution would like to investigate a way to encourage consumers to accept such novice transportation vehicles and to steer away from the disastrous experience with electronic scooter powered by plumbous acid battery, which are considered as dreadful “environmental proection” products because of their incompetent condition and inadequate design that could not satisfy consumers’ requests. Therefore, the research objective is to understand the differences that various groups of consumers need from fuel cell scooters. It can be accomplished by organizing the notes from interviews with experts on the change factors that consumers’ needs have towards motorcycle designs, and creating questionnaires for a diverse group of consumers on their comprehension and opinion on fuel cell scooter. The research results are excellent references for fuel cell manufacturers to recognize consumers’ needs for fuel cell scooters, and to invent something that is acceptable by consumers and eventually acknowledged as popular environmental proection electronic scooters. Another advantage will be to reduce the pollution that scooters bring to the environment.

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47

Liou, Jiann-Hwa, and 劉建華. "Research and Development of High-Temperature Solid-State Electrolyte Ceramic Fuel Cell." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/66068661988091697005.

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碩士
義守大學
材料科學與工程學系
87
Bismuth-oxide-containing materials have been extensively studied because of their excellent ionic conductivity at high temperatures. For obtaining a wide temperature and composition range forδ- Bi2O3 , several oxides such as rare earth oxides and transition metal oxides are used to stabilize this phase at low temperatures. In this study, a hot-pressing technique is used to fabricate these materials at different temperatures. Several analytical methods such as XRD, DTA, SEM, Dilatometric, and LCR meter method are also used to determine the relationships among dopant’s composition, phase, microstructure, and ionic conductivity. The hot-pressing method is found to be a powerful fabrication method for fully densifying bismuth-oxide-containing materials at 700℃~830℃in a short period of time 30 min . The stabilization effect ofδ- Bi2O3 is closely related to dopant’s composition. Among these oxide dopants, Y2O3 and Nb2O5 have better stabilization effects for high-temperature cubic phases. Fractographs of sintered specimens change with the phase and phase content. With the monoclinic, cubic phase, or rhombohedral phase, the corresponding fractograph is layered, intergranular, or twin-related morphology respectivity. Furthermore, the correlations between the high-temperature phase and the phase in the quenched specimen are explained from DTA curves. In these Bi2O3-MxOy binary systems, dopants Y2O3 and Nb2O5 show excellent ionic conductivities at 700℃, which are 0.049 S㎝-1 for 25 mol% Y2O3 and 0.047 S㎝-1 for 12 mol% Nb2O5.

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48

Hsieh, Tsung-Ying, and 謝宗穎. "Research of High Power Self-Pumping Glucose Oxidase Enzymatic Fuel Cell System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/72362638389594551061.

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碩士
國立中興大學
精密工程學系所
103
This study is to ameliorate the internal structure of a high power self-pumping glucose oxidase enzymatic fuel cell for optimizing its power density. The electric pump for driving the reaction solution can be replaced by the use of the height difference for power generation without an external powered pump. Carbon cloth is immobilized with the glucose enzyme as the fuel cell anode. Other structures including acrylic plate, proton exchange membrane and flow channel plate are assembled into a fuel cell stack. To reduce the fluid resistance, serpentine flow channel with round-corner were designed. In this study, the influences related to the current collector, flow rate and flow channel are discussed. The power density of the single cell can achieve the maximum 5.036 mW cm-2 at 0.38V.A high power stack can be assembled by using those designed parameters. Use T-type connector for outside pipeline, and allow the liquid can flow into each of cells equally. Through the electricity measurements, the cell assembled in series has a higher voltage than parallel. But the related power density performance, the parallel is better than series with 15 % increment.

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49

Jiang, Wei-Jhe, and 江維哲. "Research on the Integrated System of Fuel Cell with Human Power Generation." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/44300398526697627540.

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碩士
國立勤益科技大學
電機工程系
103
Because of the fuel cell have nonlinear P-I curves and the human power generation system also have nonlinear P-V curves. Therefore thesis used extension sliding mode control (ESMC) for maximum power point tracking (MPPT) of human power generation and fuel cell systems. The goal is to make the overall energy generation system can be fully utilized, while the whole power system can improve efficiency and stable power output. In order to avoid control for a long saturation state and high-speed switch at saturation value that to affect the controller switch life or cause high ripple on power output. Therefore, the value of gain constant of this controller is very important. This thesis uses extension method which can reduce the control input saturation phenomenon and high switching frequency of sliding mode control and increase the conversion efficiency and response speed. In addition, this thesis has also established two sets of MPPT controler of the actual circuit in the integrated system. This thesis has also developed an inverter. In order to stabilize the DC power into AC power can be supplied to the AC load. Finally, through experimental results validate the stability of the proposed method. The human power generation system experimental results show that overall efficiency is better than traditional sliding mode control method from 90.59% to 93.53% and faster speed of response 1.5 seconds rather than 1.9 seconds. The maximum power point tracking of fuel cell is also faster speed of response 0.9 seconds rather than 1.3 seconds and the conversion overall efficiency from 93% to 95.5% higher than traditional sliding mode control.

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50

Hsieh, Hsiang-kuei, and 謝享桂. "Research of Flywheel System Energy Harvesting Technology for Fuel Cell Hybrid Vehicles." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/22953742820330490534.

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碩士
國立臺南大學
綠色能源科技研究所碩士班
101
In this study, 2 fuel-cell hybrid systems for the energy performance comparison of fuel-cell hybrid vehicles (FCHVs) are presented. A Matlab/Simulink model was constructed, and the main power source was a fuel cell. A lithium battery and a flywheel battery were the auxiliary power sources. A vehicle driving test, FTP-75(Federal Test Procedure), was applied for 4 different control modes: mixed common output mode, normal driving charge mode, fuel-cell mode, and braking mode. FTP-75 simulated the energy requirements and energy output state of the full-motor hybrid system. The results show that the recovered energy of the flywheel battery was higher than that of the lithium battery, and the output power was close to the motor output curve. The flywheel battery can withstand rapid charging and discharging, which substantially reduces time and instantaneous motor current output. It can also effectively reduce the load on the motor. Finally, the flywheel battery enhanced the driving range of the hybrid vehicle to a greater degree than the lithium battery did under the same conditions.

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Dissertations / Theses on the topic 'Fuel cells research'

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