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The electrochemical performance of two infiltrated SOFCs (solid oxide fuel cells) and the redox cycling tolerance of such cells are presented. NiO-SDC (Sm0.2Ce0.8O1.9) was infiltrated into a porous 8YSZ (8 mol% Y2O3) support to form the anode of the infiltrated cells and LSM (La0.80Sr0.20MnO3) or Nd-nickelate (Nd2NiO4) was infiltrated into a thin porous YSZ layer to form the cathode. The power density of the Nd-nickelate infiltrated cell is higher than that of the LSM infiltrated cell suggesting it as a suitable cathode for intermediate temperature applications. The microstructure of these infiltrated solid oxide fuel cells shows a reasonable distribution of fine particles (50-100 nm) near the interface of electrodes and electrolyte and within the bulk electrodes. Despite having much lower Ni content than conventional anode supported cells, the infiltrated fuel cells exhibit a reasonable power density at low temperatures and an excellent robustness against redox cycling when air is used as the anode oxidant.

Despite of the numerous research on thermal-runaway in valve regulated lead-acid batteries, its exact cause is not well known yet and it is not clear which physical phenomena contribute to thermal rise. To have a better understanding, the main sources of heat generation in lead-acid batteries are studied using the governing equations of battery dynamics derived in Part I. The governing equations including the conservation of energy are applied to different electrochemical reactions that take place during the overcharge of the battery. The reversible and irreversible heat sources of each reaction are determined separately. To investigate the heat generation contribution of each reaction, the governing equations are solved numerically using a two-dimensional thermal-electrochemical model. In this investigation, each term in the energy equation is calculated quantitatively in order to realize its contribution to heat generation. The numerical results show that beside Joule heating, only irreversibility contributes to heat generation which in turn results into temperature rise and the reversible part has no contribution.

Mathematical modeling and numerical simulation can help increasing the efficiency, energy and power density of zinc-silver oxide batteries. It is clear that the accuracy of the modeling depends on the assumptions of the model. Among the different types of modeling, the models based on governing equation can give a very good understanding of the involved physical phenomena. Although zinc-silver oxide batteries are very mature, there do not appear to be many existing modeling based on fundamental governing equations. In the present work, a general system of governing equations for this type of batteries is presented based on the single-domain approach. The main advantage of this type of modeling is that it contains a single-domain formulation which is valid on entire cell sandwich, namely porous electrodes, separator, electrolyte reservoir and separator. The presented governing equations are solved numerically and the results are compared and verified with experimental tests.

Single cells based on Ni-CeO2-WC-YSZ anodes were investigated as an alternative material for direct methane solid oxide fuel cells. First, a YSZ electrolyte-based cell with porous YSZ as the support for electrode materials on both sides was prepared. Then electrocatalyst materials were incorporated into the porous YSZ: the anode was infiltrated with WC (25 vol.%), Ni (5 wt%) and ceria (5 wt%) precursors; and the cathode with LSM (20 vol.%) precursor. A Ni-CeO2-WC-YSZ symmetrical cell study showed that the Ni modified electrode performed stably with humidified methane at 850degC for a period of 48 hours under open circuit condition; no carbon formation was observed either with in-situ impedance spectroscopy or ex-situ scanning electron microscopy. Furthermore, the fuel cell results revealed that not only does the anode operate steadily with a reasonable performance on methane fuel, but the stability of the carbide phase is well maintained. The cell also successfully survived an oxidation-reduction-recarburization cycle. It was demonstrated that with a proper cell configuration, the structural integrity can be protected. These results suggest that a Ni modified anode is compatible with methane fuel, with reasonable and stable performance.

Thermal-runaway (TRA) is one of the failure modes in batteries. Much research has been conducted to find the exact cause of this issue and how to prevent it. Despite all these efforts, a proper model which can predict the thermal-runaway does not yet exist. In Part I of the present study, this phenomenon is considered theoretically and as a result, a general set of governing equations are presented by which the thermal behavior of batteries can be obtained. Since the proposed system of equations is general, it can be used for investigating the thermal-runaway in any kind of battery systems. In a the second part of this paper (Part II), the present model will be applied to lead-acid batteries.

The impact of porous support morphology on the electrochemical performance of LSM-infiltrated symmetrical cells was investigated. Five distinctly different porous YSZ supports were developed using different YSZ powders (as received or calcined-milled), pore formers (polymethyl methacrylate, graphite and carbon black) and sintering conditions, while the total volume fraction of open porosity was identically kept in the range of 50-55% for all the cells. The influence of size, connectivity and distribution of the pores as well as the configuration of YSZ particles on the surface area and three phase boundary length was analyzed qualitatively by scanning electron microscopy and quantitatively by the Brunauer-Emmett-Teller technique both before and after LSM infiltration into the support. Ac impedance spectroscopy studies revealed that ohmic and polarization resistance of the cells were quite varied. It was found that a calcined YSZ-based structure had the most uniform morphology and the lowest ohmic resistance (225 m*cm2 at 800degC). Low temperature sintered cells with an as received YSZ-based structure, however, exhibited the lowest polarization resistance (60 m.cm2 at 800degC). The significance of using calcined YSZ-based structures in the practical development of porous YSZ supports is discussed.

In this work, the separation and purification of 1,5-Di-O-caffeoylquinic acid (1,5 DCQA) was carried out via column chromatography (ethyl acetate/n-hexane with volume ratio 20/80) from Artichoke (Cynara scolymusL.) head ethanolic extract and characterized with IR, LC/MS, and UV/visible. The electrochemical approach has been used to analyze and detect electroactive compounds in ethanolic extract. Differential pulse voltammetry results indicated that a bioactive and electroactive molecule (1,5-Di-O-caffeoylquinic acid) is the major constituent in the Artichoke ethanolic extract. The analytical parameters are calculated via calibration curve and obtained 7.8 ?M and 9.0 ?M-1.8 mM for LOD and linear range, respectively. The theoretical and experimental biological assessment has been carried out with molecular docking, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and in vitro antibacterial susceptibility assay. The adsorption peak of DPPH is thoroughly deleted after the addition of Artichoke extract; therefore, its antioxidant activity is achieved approximately 100%. The inhibition zone surrounding the wells indicated that relevant extract has inhibitory function against E. coli(19 mm), S. enterica(21 mm), B. cereus(20 mm), and S. aureus(17 mm) bacterial. The binding affinity values showed that 1,5 DCQAhas an inhibitory effect against ROS generation enzymes and bacterial enzymes.

The electrochemical performance of two infiltrated SOFCs (solid oxide fuel cells) and the redox cycling tolerance of such cells are presented. NiO-SDC (Sm0.2Ce0.8O1.9) was infiltrated into a porous 8YSZ (8 mol% Y2O3) support to form the anode of the infiltrated cells and LSM (La0.80Sr0.20MnO3) or Nd-nickelate (Nd2NiO4) was infiltrated into a thin porous YSZ layer to form the cathode. The power density of the Nd-nickelate infiltrated cell is higher than that of the LSM infiltrated cell suggesting it as a suitable cathode for intermediate temperature applications. The microstructure of these infiltrated solid oxide fuel cells shows a reasonable distribution of fine particles (50–100 nm) near the interface of electrodes and electrolyte and within the bulk electrodes. Despite having much lower Ni content than conventional anode supported cells, the infiltrated fuel cells exhibit a reasonable power density at low temperatures and an excellent robustness against redox cycling when air is used as the anode oxidant.

Despite of the numerous research on thermal–runaway in valve regulated lead–acid batteries, its exact cause is not well known yet and it is not clear which physical phenomena contribute to thermal rise. To have a better understanding, the main sources of heat generation in lead–acid batteries are studied using the governing equations of battery dynamics derived in Part I. The governing equations including the conservation of energy are applied to different electrochemical reactions that take place during the overcharge of the battery. The reversible and irreversible heat sources of each reaction are determined separately. To investigate the heat generation contribution of each reaction, the governing equations are solved numerically using a two–dimensional thermal–electrochemical model. In this investigation, each term in the energy equation is calculated quantitatively in order to realize its contribution to heat generation. The numerical results show that beside Joule heating, only irreversibility contributes to heat generation which in turn results into temperature rise and the reversible part has no contribution.

Single cells based on Ni-CeO2-WC-YSZ anodes were investigated as an alternative material for direct methane solid oxide fuel cells. First, a YSZ electrolyte-based cell with porous YSZ as the support for electrode materials on both sides was prepared. Then electrocatalyst materials were incorporated into the porous YSZ: the anode was infiltrated with WC (25 vol.%), Ni (5 wt%) and ceria (5 wt%) precursors; and the cathode with LSM (20 vol.%) precursor. A Ni-CeO2-WC-YSZ symmetrical cell study showed that the Ni modified electrode performed stably with humidified methane at 850°C for a period of 48 hours under open circuit condition; no carbon formation was observed either with in-situ impedance spectroscopy or ex-situ scanning electron microscopy. Furthermore, the fuel cell results revealed that not only does the anode operate steadily with a reasonable performance on methane fuel, but the stability of the carbide phase is well maintained. The cell also successfully survived an oxidation-reduction-recarburization cycle. It was demonstrated that with a proper cell configuration, the structural integrity can be protected. These results suggest that a Ni modified anode is compatible with methane fuel, with reasonable and stable performance.

Mathematical modeling and numerical simulation can help increasing the efficiency, energy and power density of zinc–silver oxide batteries. It is clear that the accuracy of the modeling depends on the assumptions of the model. Among the different types of modeling, the models based on governing equation can give a very good understanding of the involved physical phenomena. Although zinc–silver oxide batteries are very mature, there do not appear to be many existing modeling based on fundamental governing equations. In the present work, a general system of governing equations for this type of batteries is presented based on the single–domain approach. The main advantage of this type of modeling is that it contains a single–domain formulation which is valid on entire cell sandwich, namely porous electrodes, separator, electrolyte reservoir and separator. The presented governing equations are solved numerically and the results are compared and verified with experimental tests.

Thermal–runaway (TRA) is one of the failure modes in batteries. Much research has been conducted to find the exact cause of this issue and how to prevent it. Despite all these efforts, a proper model which can predict the thermal–runaway does not yet exist. In Part I of the present study, this phenomenon is considered theoretically and as a result, a general set of governing equations are presented by which the thermal behavior of batteries can be obtained. Since the proposed system of equations is general, it can be used for investigating the thermal–runaway in any kind of battery systems. In a the second part of this paper (Part II), the present model will be applied to lead–acid batteries.

The impact of porous support morphology on the electrochemical performance of LSM-infiltrated symmetrical cells was investigated. Five distinctly different porous YSZ supports were developed using different YSZ powders (as received or calcined-milled), pore formers (polymethyl methacrylate, graphite and carbon black) and sintering conditions, while the total volume fraction of open porosity was identically kept in the range of 50–55% for all the cells. The influence of size, connectivity and distribution of the pores as well as the configuration of YSZ particles on the surface area and three phase boundary length was analyzed qualitatively by scanning electron microscopy and quantitatively by the Brunauer-Emmett-Teller technique both before and after LSM infiltration into the support. Ac impedance spectroscopy studies revealed that ohmic and polarization resistance of the cells were quite varied. It was found that a calcined YSZ-based structure had the most uniform morphology and the lowest ohmic resistance (225 mΩ·cm2at 800°C). Low temperature sintered cells with an as received YSZ-based structure, however, exhibited the lowest polarization resistance (60 mΩ.cm2at 800°C). The significance of using calcined YSZ-based structures in the practical development of porous YSZ supports is discussed.