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1.	Eidehall, Andreas, et al. (author) Joint Road Geometry Estimation and Vehicle Tracking 2007 In: Control Engineering Practice. - Linköping : Elsevier. - 0967-0661 .- 1873-6939. ; 15:12, s. 1484-1494 Journal article (peer-reviewed)abstract Detection and tracking of other vehicles and estimation of lane geometry will be required for many intelligent driver assistance systems in the future. By combining the processing of these two features into a single filter, better utilisation of the available information can be achieved. For instance, it is demonstrated that it is possible to improve the road shape estimate by including information about the lateral movement of leading vehicles. Statistical evaluation is done by comparing the estimated parameters to true values in varying road and weather conditions. The performance is also related to typical requirements of active safety applications such as adaptive cruise control and a new safety function called emergency lane assist.
2.	Folkesson, Anders, et al. (author) Real life testing of a hybrid PEM fuel cell bus 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 118:1-2, s. 349-357 Journal article (peer-reviewed)abstract Fuel cells produce low quantities of local emissions, if any, and are therefore one of the most promising alternatives to internal combustion engines as the main power source in future vehicles. It is likely that urban buses will be among the first commercial applications for fuel cells in vehicles. This is due to the fact that urban buses are highly visible for the public, they contribute significantly to air pollution in urban areas, they have small limitations in weight and volume and fuelling is handled via a centralised infrastructure. Results and experiences from real life measurements of energy flows in a Scania Hybrid PEM Fuel Cell Concept Bus are presented in this paper. The tests consist of measurements during several standard duty cycles. The efficiency of the fuel cell system and of the complete vehicle are presented and discussed. The net efficiency of the fuel cell system was approximately 40% and the fuel consumption of the concept bus is between 42 and 48% lower compared to a standard Scania bus. Energy recovery by regenerative braking saves up 28% energy. Bus subsystems such as the pneumatic system for door opening, suspension and brakes, the hydraulic power steering, the 24 V grid, the water pump and the cooling fans consume approximately 7% of the energy in the fuel input or 17% of the net power output from the fuel cell system. The bus was built by a number of companies in a project partly financed by the European Commission's Joule programme. The comprehensive testing is partly financed by the Swedish programme "Den Grona Bilen" (The Green Car). A 50 kW(el) fuel cell system is the power source and a high voltage battery pack works as an energy buffer and power booster. The fuel, compressed hydrogen, is stored in two high-pressure stainless steel vessels mounted on the roof of the bus. The bus has a series hybrid electric driveline with wheel hub motors with a maximum power of 100 kW. Hybrid Fuel Cell Buses have a big potential, but there are still many issues to consider prior to full-scale commercialisation of the technology. These are related to durability, lifetime, costs, vehicle and system optimisation and subsystem design. A very important factor is to implement an automotive design policy in the design and construction of all components, both in the propulsion system as well as in the subsystems.
3.	Selimovic, Azra, et al. (author) Networked solid oxide fuel cell stacks combined with a gas turbine cycle 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:1-2, s. 76-82 Conference paper (peer-reviewed)abstract An improved design of fuel cells stacks arrangement has been suggested before for MCFC where reactant streams are ducted such that they are fed and recycled among multiple MCFC stacks in series. By networking fuel cell stacks, increased efficiency, improved thermal balance, and higher total reactant utilisation can be achieved. In this study, a combination of networked solid oxide fuel cell (SOFC) stacks and a gas turbine (GT) has been modelled and analysed. In such a combination, the stacks are operating in series with respect to the fuel flow. In previous studies conducted on hybrid SOFC/GT cycles by the authors, it was shown that the major part of the output of such cycles can be addressed to the fuel cell, In those studies, a single SOFC with parallel gas flows to individual cells were assumed. It can be expected that if the performance of the fuel cell is enhanced by networking, the overall system performance will improve. In the first part of this paper, the benefit of the networked stacks is demonstrated for a stand alone stack while the second part analyses and discusses the impact networking of the stacks has on the SOFC/GT system performance and design. For stacks with both reactant streams in series, a significant increase of system efficiency was found (almost 5% points), which, however, can be explained mainly by an improved thermal management.
4.	Agrell, J., et al. (author) Steam reforming of methanol over a Cu/ZnO/Al2O3 catalyst : a kinetic analysis and strategies for suppression of CO formation 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:1-2, s. 249-257 Conference paper (peer-reviewed)abstract Steam reforming of methanol (CH3OH + H2O --> CO2 + 3H(2)) was studied over a commercial Cu/ZnO/Al2O3 catalyst for production of hydrogen onboard proton exchange membrane (PEM) fuel cell vehicles. A simple power-law rate expression was fitted to experimental data in order to predict the rates Of CO2 and H-2 formation under various reaction conditions. The apparent activation energy (E-a) was estimated to be 100.9 kJ mol(-1), in good agreement with values reported in the literature. Appreciable amounts of CO by-product were formed in the reforming process at low contact times and high methanol conversions. Being a catalyst poison that deactivates the electrocatalyst at the fuel cell anode at concentrations exceeding a few ppm, special attention was paid to the pathways for CO formation and strategies for its suppression. It was found that increasing the steam-methanol ratio effectively decreases CO formation. Likewise, addition of oxygen or air to the steam-methanol mixture minimises the production of CO. By shortening the contact time and lowering the maximum temperature in the reactor, CO production can be further decreased by suppressing the reverse water-gas shift reaction.
5.	Andersson, Anna M, et al. (author) Electrochemically lithiated graphite characterised by photoelectron spectroscopy 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 119-121, s. 522-527 Journal article (peer-reviewed)abstract X-ray photoelectron spectroscopy (XPS) has been used to study the depth profile of the solid–electrolyte interphase (SEI) formed on a graphite powder electrode in a Li-ion battery. The morphology of the SEI-layer, formed in a 1 M LiBF4 EC/DMC 2:1 solution, consists of a 900 Å porous layer of polymers (polyethylene oxide) and a 15–20 Å thin layer of Li2CO3 and LiBF4 reduction–decomposition products. Embedded LiF crystals as large as 0.2 μm were found in the polymer matrix. LiOH and Li2O are not major components on the surface but rather found as a consequence of sputter-related reactions. Monochromatised Al Kα XPS-analysis based on the calibration of Ar+ ion sputtering of model compounds combined with a depth profile analysis based on energy tuning of synchrotron XPS can describe the highly complex composition and morphology of the SEI-layer.
6.	Doeff, M.M, et al. (author) Transport properties of binary salt polymer electrolytes 2000 In: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 89:2, s. 227-231 Journal article (peer-reviewed)abstract Transport properties (ionic conductivities (σ), salt diffusion coefficients (Ds), and cationic transference numbers (t+0)) as a function of salt concentration (Cs) are reported and compared for several common binary salt/polymer systems being considered for use as electrolytes in rechargeable lithium batteries for electric vehicle and other applications. The three properties provide a complete description of transport in solid polymer electrolytes (SPEs) or "dry" systems in cells undergoing galvanostatic charge and discharge. The macroscopic approach used obviates the need to know the details of speciation in these non-ideal solutions and allows for a more sophisticated correlation of the characteristics of ion transport with polymer structure, salt type, and concentration than conductivity data alone.
7.	Escudero, M. J., et al. (author) Development and performance characterisation of new electrocatalysts for PEMFC 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:1-2, s. 206-214 Conference paper (peer-reviewed)abstract New electrocatalysts based on Pt, Pt-Ru and Pt-Pd have been prepared by the microemulsion method. This method allows the production of a very narrow size distribution of metal particles, with an average size smaller than that of conventional electrocatalysts prepared by impregnation. Eight membrane electrode assemblies (MEAs) with an active surface area of 50 cm(2) were characterised in a single fuel cell. The MEAs consist of Nation 117 as membrane and a commercial electrocatalyst (40% Pt/C from E-TEK) on the cathode side, Four MEAs have electrocatalysts prepared by the microemulsion technique and the other four have commercial electrocatalysts on the anode side. The performance of the eight MEAs was evaluated by measuring the fuel cell polarisation curves and the internal resistance with H-2/O-2 and H-2/air, at 60 T and pressure in the range from I to 3 bar. The MEAs with the electrocatalysts prepared by microemulsion showed a performance comparable to that of the MEAs with commercial electrocatalysts. The satisfactory results obtained show that microemulsion is a promising method for the preparation of electrocatalysts for fuel cells. Further effort will be devoted to the optimisation of the method, mainly, the deposition of the metal particles on the carbon support, which it is expected to enhance the fuel cell performance.
8.	Fu, Q. X., et al. (author) Intermediate temperature fuel cells based on doped ceria-LiCl-SrCl2 composite electrolyte 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 104:1, s. 73-78 Journal article (peer-reviewed)abstract A new type of oxide-salt composite electrolyte, gadolinium-doped ceria (GDC)-LiCl-SrCl2, was developed and demonstrated its promising use for intermediate temperature (400-700 degreesC) fuel cells (ITFCs). The dc electrical conductivity of this composite electrolyte (0.09-0.13 S cm(-1) at 500-650 degreesC) was 3-10 times higher than that of the pure GDC electrolyte, indicating remarkable proton or oxygen ion conduction existing in the LiCl-SrCl2 chloride salts or at the interface between GDC and the chloride salts. Using this composite electrolyte, peak power densities of 260 and 510 mW cm(-2), with current densities of 650 and 1250 mA cm(-2) were achieved at 550 and 625 degreesC, respectively. This makes the new material a good candidate electrolyte for future low-cost ITFCs.
9.	Georen, P., et al. (author) On the use of voltammetric methods to determine electrochemical stability limits for lithium battery electrolytes 2003 In: Journal of Power Sources. - : Elsevier BV. - 0378-7753 .- 1873-2755. ; 124:1, s. 213-220 Journal article (peer-reviewed)abstract In previous studies a novel amphiphilic co-polymer was developed for use in lithium-ion batteries. In order to evaluate the electrochemical stability of that electrolyte and compare it with others, a voltammetric method was applied on a set of electrolytes with different salts, solvents and polymers. However, initially the voltammetric methodology was studied. Platinum was found to be the most suited electrode material, experiencing no significant interfering reactions and a proper diffusion-controlled kinetic behaviour when sweep rate was varied. Furthermore, the influence on the voltammograms of adding water traces to the electrolytes was studied. It could be established that the oxidation peak around 3.8 V versus Li was related to water reactions. It was concluded that quantitative voltage values of the stability limits were difficult to assess using voltammetry. On the other hand, the method seemed well suited for comparison of electrolytes and to investigate the influences of electrolyte components on the stability. The voltammetric results varied little between the different electrolytes evaluated and the anodic and cathodic limits, as defined here, were in the range of I and 4.5 V vs. Li, respectively. Although the novel polymer did not affect the stability limit significantly it seemed to promote the breakdown reaction rate in all electrolytes tested. Furthermore, the use of LiTFSI salt reduced the stability window.
10.	Herstedt, Marie, et al. (author) Rate capability of natural graphite as anode material in Li-ion batteries 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 124:1, s. 191-196 Journal article (peer-reviewed)abstract Jet-milled natural Swedish graphite has been evaluated as an anode material for Li-ion battery applications, with a focus on rate capability of the material. The material was found to have a superior rate capability compared to other carbon materials with similar particle sizes. It could also intercalate and deintercalate lithium reversibly in an electrolyte based on propylene carbonate:ethylene carbonate (1:1). Jet-milling was found to increase the amount of rhombohedral phase (3R) in the material from 15 to 40%. However, after repeated electrochemical intercalation and deintercalation of lithium, the amount of 3R phase decreases to ~5%. Neither rate capability nor PC-tolerance can therefore be correlated to the amount of 3R phase.
11.	Kiros, Yohannes, 1956-, et al. (author) Cobalt and cobalt-based macrocycle blacks as oxygen-reduction catalysts in alkaline fuel cells 1993 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 45:2, s. 219-227 Journal article (peer-reviewed)abstract The electrochemical reduction of oxygen on high surface are carbons catalyzed by cobalt and pyrolyzed macrocycles has been studied in alkaline fuel cells. Tests were also carried out with 'green black', i.e., pyrolyzed phyto-biomass. Galvanostatic polarization curves show that cobalt from cobalt acetate and fine cobalt metal power exhibit a high catalytic activity. The activity of pyrolyzed cobalt tetraphenylporphyrin (CoTPP) is due to the combined effects of the cobalt additive and the charred residue of the macrocycle. 'Green black', with chlorophyll as macrocycle black precursor, has a similar effect. The dissolution of cobalt from the electrode surface has been established. Life tests with these electrodes are reported. Â© 1993.
12.	Kiros, Yohannes, et al. (author) Long-term hydrogen oxidation catalysts in alkaline fuel cells 2000 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 87:02-jan, s. 101-105 Journal article (peer-reviewed)abstract Pt/Pd bimetallic combination and Raney Ni catalysts were employed in long-term electrochemical assessment of the hydrogen oxidation reaction (HOR) in 6 M KOH. Steady-state current vs. potential measurements of the gas diffusion electrodes have shown high activity for these types of catalysts. Durability tests of the electrodes have shown increased stability for the Pt/Pd-based catalysts than the Raney Ni at a constant load of 100 mA/cm(2) and at temperatures of 55 degrees C and 60 degrees C, respectively. Surface, structural and chemical analyses by BET surface area, transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) were used to characterize the composite electrode/catalyst both before and after the electrochemical testing.
13.	Kivisaari, T., et al. (author) Studies of biomass fuelled MCFC systems 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 104:1, s. 115-124 Journal article (peer-reviewed)abstract In the present work, the methods, techniques and results obtained during the studies of biomass fuelled molten carbonate fuel cell (MCFC) systems within the Swedish national fuel cell program are presented. The power plants are 60 MW class, utilising biomass (i.e. wood chips) as the primary fuel. The biomass is converted via pressurised gasification into a gaseous form that, after subsequent cleaning, can be used in the fuel cells. An investigation of the effects of gasification pressure, temperature and the influence of internal reforming on the overall system performance is presented. All studies were carried out using the Aspen Plus(TM) with Model Manager(TM) simulation package.
14.	Lindström, B., et al. (author) Development of a methanol fuelled reformer for fuel cell applications 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 118:02-jan, s. 71-78 Journal article (peer-reviewed)abstract A compact methanol reformer for fuel cell vehicles (FCVs) has, been developed and successfully tested. The reformer which has been constructed to serve a 5 Me fuel cell operates by combined reforming of methanol (CRM) (a combination of steam reforming and partial oxidation). The exploitable energy surplus in a fuel cell vehicle is low and therefore a combustion system for heating the reformer which utilizes a catalyst for both evaporation and oxidation of liquid methanol was developed. We were able to obtain start-up times in the region of 4-6 min depending on the oxygen-to-methanol ratio (OMR) used for the combined reforming reaction. The main drawback from decreasing the start-up time by increasing the oxygen-to-methanol ratio was that the CO concentrations in the product stream increased. The reforming reaction was performed over copper-based catalysts while the oxidation took place over a mixture of platinum and manganese-based catalysts. The catalysts were characterized using SEM-EDS, BET surface area measurement and X-ray diffraction (XRD).
15.	Lindström, B., et al. (author) Steam reforming of methanol over copper-based monoliths : the effects of zirconia doping 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:02-jan, s. 264-273 Journal article (peer-reviewed)abstract In this paper, an experimental investigation concerning steam reforming of methanol over various alumina-supported monolithic copper-based catalysts is presented. The activity and carbon dioxide selectivity was studied over two sets of catalysts, one of which was doped with zirconium, with five different copper contents. The zirconium-doped catalyst were less active with respect to the hydrogen yield, however, they were at all times more selective towards carbon dioxide over the entire temperature interval. The catalysts have been characterised using Brunauer-Emmett-Teller (BET) surface area measurement and X-ray diffraction (XRD). The results show that the copper loading and modification of the active material by zirconia doping had a great influence on the methanol conversion and carbon dioxide selectivity of the steam reforming reaction.
16.	Lundblad, Anders, et al. (author) Effect of sintering procedures in development of LiCoO2-cathodes for the molten carbonate fuel cell 2000 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 90:2, s. 224-230 Journal article (peer-reviewed)abstract LiCoO2-powder was synthesized from carbonate precursors by calcination in air. Greentapes were tape-cast using a non-aqueous slurry and 10 mu m plastic spheres as pore formers. Sintering was carried out in air at 850-950 degrees C and in argon/air at 500/750 degrees C, The two sintering procedures led to very different sub-micron morphologies, with the primary particles being much smaller in the latter case. The electrochemical performance at 650 degrees C, in terms of overpotential at 160 mA/cm(2), for the air- and argon/air-sintered electrodes was 57 and 81 mV, respectively. The potential drop due to contact resistance between electrode and current collector was estimated to be 100 and 70 mV, respectively. The electrode materials were characterized by scanning electron microscopy (SEM), Hg-porosimetry, the BET-method (N-2-adsorption), X-ray diffractometry (XRD), flame atomic absorption spectrometry (F-AAS), carbon analysis and a van der Pauw conductivity measurement set-up.
17.	Pirjamali, M., et al. (author) Effects of carbon pretreatment for oxygen reduction in alkaline electrolyte 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 109:2, s. 446-451 Journal article (peer-reviewed)abstract The effects of different media on carbon pretreatments for oxygen reduction in alkaline electrolyte without application of active electrocatalysts were examined. Low surface area Vulcan XC-72 and high surface area Ketjenblack EC-300 were subjected to aqueous acid (flouric or formic), gaseous (H-2, N-2 or CO2) and thermal treatments at 600 or 900 degreesC. Though non-scrubbed air was used, as a result of which carbonate build-up was high and peroxide concentration increased due to the electrode reaction, some of the electrodes resulted in life-tests of more than 2000 h at 65 degreesC, 6 M KOH with a constant load of 50 mA cm(-2) and intermittent polarisations at higher current densities. BET-surface areas and pH changes of more than 60% and weight losses of up to 15% of the carbon blacks were observed after the pretreatment steps. Electrochemical characterisation of the carbons showed that pretreatment steps of the carbon blacks have a significant effect on the long-term stability and activity of the gas diffusion electrodes in alkaline electrolyte.
18.	Wallmark, Cecilia, et al. (author) Design of stationary PEFC system configurations to meet heat and power demands 2002 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:02-jan, s. 83-92 Journal article (peer-reviewed)abstract This paper presents heat and power efficiencies of a modeled PEFC system and the methods used to create the system configuration. The paper also includes an example of a simulated fuel cell system supplying a building in Sweden with heat and power. The main method used to create an applicable fuel cell system configuration is pinch technology. This technology is used to evaluate and design a heat exchanger a PEFC system working under stationary conditions, in order to find a solution with high heat utilization. The heat exchanger network for network in the system connecting the reformer, the burner, gas cleaning, hot-water storage and the PEFC stack will affect the heat transferred to the hot-water storage and thereby the heating of the building. The fuel, natural gas, is reformed to a hydrogen-rich gas within a slightly pressurized system. The fuel processor investigated is steam reforming, followed by high- and low-temperature shift reactors and preferential oxidation. The system is connected to the electrical grid for backup and peak demands and to a hot-water storage to meet the varying heat demand for the building. The procedure for designing the fuel cell system installation as co-generation system is described, and the system is simulated for a specific building in Sweden during I year. The results show that the fuel cell system in combination with a burner and hotwater storage could supply the building with the required heat without exceeding any of the given limitations. The designed co-generation system will provide the building with most of its power requirements and would further generate income by sale of electricity to the power grid.
19.	Wallmark, Cecilia, et al. (author) Design of stationary PEFC system configurations to meet heat and power demands 2002 In: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 106:1-2, s. 83-92 Journal article (peer-reviewed)
20.	Wallmark, Cecilia, et al. (author) Technical design and economic evaluation of a stand-alone PEFC system for buildings in Sweden 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 118:02-jan, s. 358-366 Journal article (peer-reviewed)abstract This paper deals with the prerequisites for a stand-alone fuel cell system installed to avoid replacing or upgrading an ageing, distant power grid connection which only supplies a few buildings with their power demands. The importance of sizing the included components in the energy system is presented in economic terms. The size of the fuel cell system and the energy storage system (battery, hot-water storage and hydrogen storage) are discussed in relation to the yearly distribution of the buildings' power demand. The main design idea is to decrease the size of the fuel cell system without making the battery too expensive and that the power requirements are fulfilled over test periods with decided length and power output. The fuel cell system installation is not economically viable for the presented conditions, but in the paper future feasible scenarios are presented. The calculated incomes are shown as a function of the size of the fuel cell system and energy storage, the electricity costs, the fuel costs including transportation, the prices of electricity and heat, and the fuel cell system costs and efficiencies. The main factor in the system's economic performance is the fuel price, which contributes more than half the costs for the fuel cell system-based energy system. The cost of the power grid is also determining for the result, where the distance to the main power grid is the important factor. The evaluation is performed from the utility company's point of view.
21.	Wallmark, Cecilia, et al. (author) Technical design and economic evaluation of a stand-alone PEFC system for buildings in Sweden 2003 In: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 118:1-2, s. 358-366 Journal article (peer-reviewed)
22.	Zhu, Bin (author) Advantages of intermediate temperature solid oxide fuel cells for tractionary applications 2001 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 93:02-jan, s. 82-86 Journal article (peer-reviewed)abstract Our recent achievements suggest that intermediate temperature (IT) solid oxide fuel cells (SOFCs) can become a strong competitor not only for stationary power generation, but also for tractionary applications, e.g. for electrical (hybrid) vehicles. These ITSOFCs are based on ceria-salt composite ceramic materials. These new ceria-based composite ceramic materials have shown a super ionic conductivity (0.1-1.0 S cm(-1)) in the IT region (400-600 degreesC). Using them as the electrolytes the ITSOFCs are operated between 300 and 1500 mA cm(-2) (200-700 mW cm(-2)) continuously between 400 and 600 degreesC. The opportunities and advantages of these new advanced ITSOFCs for electrical vehicle applications are discussed. The high efficiency ITSOFCs fed directly with hydrocarbon containing gas-type and liquid-type fuels have shown an enormous potential for application in electrical vehicles.
23.	Zhu, Bin (author) Functional ceria-salt-composite materials for advanced ITSOFC applications 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 114:1, s. 1-9 Journal article (peer-reviewed)abstract This paper reports our current material research and development for advanced intermediate temperature (IT, 400-700 degreesC) solid oxide fuel cells (SOFCs). The materials reported in this work are based on ceria-salt-composites, which have super function, e.g. displaying ionic conductivity of 0.01-1 S cm(-1) in the IT region. They are functional ceramic materials for advanced ITSOFC applications. When these new composites are used as ITSOFC electrolytes, a performance of 300-800 mW cm(-2) between 400 and 650 degreesC has been demonstrated.
24.	Zhu, Bin, et al. (author) Innovative low temperature SOFCs and advanced materials 2003 In: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 118:02-jan, s. 47-53 Journal article (peer-reviewed)abstract High ionic conductivity, varying from 0.01 to 1 S cm(-1) between 300 and 700 degreesC, has been achieved for the hybrid and nano-ceriacomposite electrolyte materials, demonstrating a successful application for advanced low temperature solid oxide fuel cells (LTSOFCs). The LTSOFCs were constructed based on these new materials. The performance of 0.15-0.25 W cm(-2) was obtained in temperature region of 320400 degreesC for the ceria-carbonate composite electrolyte, and of 0.35-0.66 W cm(-2) in temperature region of 500-600 degreesC for the ceria-lanthanum oxide composites. The cell could even function at as low as 200 degreesC. The cell has also undergone a life test for several months. A two-cell stack was studied, showing expected performance successfully. The excellent LTSOFC performance is resulted from both functional electrolyte and electrode materials. The electrolytes are two phase composite materials based on the oxygen ion and proton conducting phases, or two rare-earth oxides. The electrodes used were based on the same composite material system having excellent compatibility with the electrolyte. They are highly catalytic and conductive thus creating the excellent performances at low temperatures. These innovative LT materials and LTSOFC technologies would open the door for wide applications, not only for stationary but also for mobile power sources.
25.	Afzal, Muhammad, et al. (author) Fabrication of novel electrolyte-layer free fuel cell with semi-ionic conductor (Ba0.5Sr0.5Co0.8Fe0.2O3-delta- Sm0.2Ce0.8O1.9) and Schottky barrier 2016 In: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 328, s. 136-142 Journal article (peer-reviewed)abstract Perovskite Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCF) is synthesized via a chemical co-precipitation technique for a low temperature solid oxide fuel cell (LTSOFC) (300-600 degrees C) and electrolyte-layer free fuel cell (EFFC) in a comprehensive study. The EFFC with a homogeneous mixture of samarium doped ceria (SDC): BSCF (60%:40% by weight) which is rather similar to the cathode (SDC: BSCF in 50%:50% by weight) used for a three layer SOFC demonstrates peak power densities up to 655 mW/cm(2), while a three layer (anode/ electrolyte/cathode) SOFC has reached only 425 mW/cm(2) at 550 degrees C. Chemical phase, crystal structure and morphology of the as-prepared sample are characterized by X-ray diffraction and field emission scanning electron microscopy coupled with energy dispersive spectroscopy. The electrochemical performances of 3-layer SOFC and EFFC are studied by electrochemical impedance spectroscopy (EIS). As-prepared BSCF has exhibited a maximum conductivity above 300 S/cm at 550 degrees C. High performance of the EFFC device corresponds to a balanced combination between ionic and electronic (holes) conduction characteristic. The Schottky barrier prevents the EFFC from the electronic short circuiting problem which also enhances power output. The results provide a new way to produce highly effective cathode materials for LTSOFC and semiconductor designs for EFFC functions using a semiconducting-ionic material.

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