The Experts below are selected from a list of 18756 Experts worldwide ranked by ideXlab platform
Faouzi Askri - One of the best experts on this subject based on the ideXlab platform.
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Numerical investigation of high temperature Metal Hydride water pumping system
International Journal of Hydrogen Energy, 2019Co-Authors: Faouzi Askri, Amel Miled, Sofiene Mellouli, Hatem Ben MâadAbstract:Abstract I n the present work, a high temperature Metal Hydride Water Pumping System (MHWPS) equipped with a latent heat exchanger was investigated numerically. The operating concept of the pump was presented and the mathematical model of heat and mass transfer within the pump was established. We simulated the pump under different operating conditions using the alloy Mg2Ni as a Metal Hydride and the KNO3 as a Phase Change Material (PCM). The obtained results have shown that i) the developed numerical model is flexible and accurate in predicting the dynamic behavior of the pump ii) the numerical model without radiative heat transfer gives results with errors that can reach 38%, particularly for pumping time iii) the integration of the PCM provides a reduction in the pumping time of about 90% and an increase of the efficiency of the pump of about 7.6 times compared to the case without PCM which represents an improvement of 86% and iv) the Mg2Ni alloy requires high temperature and a mass of PCM about 9 times larger than the case of LaNi5 alloy to pump a volume 6.5 times greater than that pumped with LaNi5.
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Experimental study and characterization of Metal Hydride containers
International Journal of Hydrogen Energy, 2011Co-Authors: A. Souahlia, Faouzi Askri, Sofiene Mellouli, H. Dhaou, Abdelmajid Jemni, S. Ben NasrallahAbstract:Two Metal Hydride containers were built at the laboratory respecting a simple and modular design for the purpose of getting useful knowledge about the similarity of elements of Metal Hydride containers relevant in the prediction of larger size storage unit behaviour. In this paper, we present a description of the containers and an investigation of the parameters influencing the hydrogen storage performance.
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Parametric studies on a Metal-Hydride cooling system
International Journal of Hydrogen Energy, 2009Co-Authors: Sofiene Mellouli, Faouzi Askri, H. Dhaou, A. Jemni, S. Ben NasrallahAbstract:A mathematical model and software set for computer simulation of operational Metal-Hydride cooling system are developed. The numerical model is able to take into account the coupled heat- and mass-transfer equations of the two reactors. Thus the model allows us to know and to foresee the effects of operational and design parameters on the performance of the Metal-Hydride cooling system. The model was validated by being compared to experimental data obtained by other authors and good agreements were obtained. Using this model, the effects of operating parameters are presented and discussed.
C J Webb - One of the best experts on this subject based on the ideXlab platform.
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a review of mathematical modelling of Metal Hydride systems for hydrogen storage applications
International Journal of Hydrogen Energy, 2016Co-Authors: S S Mohammadshahi, Maca E Gray, C J WebbAbstract:Metal-Hydrides have been of great interest as one of the most promising materials for hydrogen storage applications. For widespread use, the most appropriate container and thermal management systems to minimise the time of absorption and desorption and maximise the amount of stored hydrogen must be designed. In recent years, many attempts have been made to identify the relationship between different operating and design variables and the resultant performance of Metal-Hydride systems. In this review, features of mathematical models of Metal-Hydride reactors including the assumptions, different applied equations and solution methods which have been developed in previous studies are presented. The evolution of the reactor geometries and configurations of cooling systems as well as different effective factors of Metal-Hydride performance are also discussed.
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A review of mathematical modelling of Metal-Hydride systems for hydrogen storage applications
International Journal of Hydrogen Energy, 2016Co-Authors: S S Mohammadshahi, E. Maca. Gray, C J WebbAbstract:Metal-Hydrides have been of great interest as one of the most promising materials for hydrogen storage applications. For widespread use, the most appropriate container and thermal management systems to minimise the time of absorption and desorption and maximise the amount of stored hydrogen must be designed. In recent years, many attempts have been made to identify the relationship between different operating and design variables and the resultant performance of Metal-Hydride systems. In this review, features of mathematical models of Metal-Hydride reactors including the assumptions, different applied equations and solution methods which have been developed in previous studies are presented. The evolution of the reactor geometries and configurations of cooling systems as well as different effective factors of Metal-Hydride performance are also discussed.Griffith Sciences, School of Natural SciencesNo Full Tex
Nobuhiro Kuriyama - One of the best experts on this subject based on the ideXlab platform.
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hydrogen storage alloys with puni3 type structure as Metal Hydride electrodes
Electrochemical and Solid State Letters, 1999Co-Authors: Jun Chen, Hiroyuki T Takeshita, Nobuhiro Kuriyama, Hideaki Tanaka, Tetsuo Sakai, Masatake HarutaAbstract:A powder sintering method was used to synthesize the interMetallic compounds , , , and . The microstructure and primary phases were observed by scanning electron microscopy and X‐ray diffraction. The pressure‐composition isotherms showed that all alloys could reversibly absorb and desorb up to hydrogen at and a hydrogen pressure of . The sintered samples were employed as the active materials of Metal Hydride electrodes. The Hydride stability and electrochemical performance, combined with low cost raw materials, make these compounds attractive for Metal Hydride electrodes. ©2000 The Electrochemical Society
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Optimization of Fabrication Conditions of Metal-Hydride Electrode Rechargeable with Hydrogen Gas
Hydrogen Power: Theoretical and Engineering Solutions, 1998Co-Authors: Nobuhiro Kuriyama, Hiroyuki T Takeshita, Itsuki Uehara, Hideaki Tanaka, Tetsuo Sakai, T IwasakiAbstract:An air-Metal Hydride (Air-MH) battery has been studied as one of energy conversion systems with a high energy density for electric vehicles (theoretical capacity: 458 Wh-kg-1 for Air-LaNi5H6) [1,2]. The Metal-Hydride negative electrode of this battery is recharged by exposing it to hydrogen gas (H2-recharge), and also electrochemically recharged by use of an additional electrode for oxygen evolution. Therefore the Air-MH battery is suitable for the use in the future community in which both hydrogen gas and electricity are available. We have developed a Metal Hydride electrode for this battery, and showed that the electrode was recharged with hydrogen gas at the rate comparable to usual electrochemical recharging [3].
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electrochemical impedance and deterioration behavior of Metal Hydride electrodes
Journal of Alloys and Compounds, 1993Co-Authors: Nobuhiro Kuriyama, Hiroshi Miyamura, Itsuki Uehara, Tetsuo Sakai, Hiroshi Ishikawa, Toshikatsu IwasakiAbstract:Abstract Electrochemical impedance spectroscopy (EIS) was applied to Metal Hydride electrodes. Cole-Cole plots for the electrodes consisted of two obvious semicircles and a slope related to Warburg impedance. The semicircle in the high-frequency region was mainly related to the resistance and capacitance between the current collector and the pellet of alloy powder. The semicircle in the low-frequency region, which exhibited appreciable dependence on hydrogen content, was attributed to electrode reactions on the alloy particles and double-layer capacitance on the alloy particles. Resistance and capacitance between alloy particles in the electrodes also need to be taken into account. Deterioration processes of Metal Hydride electrodes using a mischMetal-based alloy, MmNi 3.5 Co 0.7 Al 0.8 , were also studied employing EIS. Deterioration of a Metal Hydride electrode using copper-coated alloy powder was dominated by a decrease in reactivity of the alloy surface. In contrast, an increase in the contact resistances and a decrease in the amount of electrochemically utilizable alloy particles were significant in the deterioration of electrodes using uncoated alloy powder. Deterioration of the electrodes was avoided to some extent by elevating the hot-press temperature during electrode preparation.
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Nickel-Metal Hydride battery for electric vehicles
Journal of Alloys and Compounds, 1993Co-Authors: Tetsuo Sakai, Hiroshi Miyamura, Nobuhiro Kuriyama, Itsuki Uehara, U. Kajiyama, Mariko Muta, A. Takagi, K. Kinoshita, F. IsogaiAbstract:When a nickel-powder-mixed alloy electrode using MmNi3.5Co0.7Al0.8 (Mm = mischMetal) was held in a complete discharge state at 40 °C, a severe capacity decrease due to passivation was observed. This capacity lowering was prevented by a nickel (copper) coating or by a cobalt powder mixing. The alloy MmNi3.8Co0.5Mn0.4Al0.3 did not cause passivation even for the nickel-mixed alloy. Prismatic nickel-Metal Hydride batteries (30–60 A h) were constructed using the alloy electrodes and evaluated as an electric vehicle battery.
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Solid-state Metal Hydride batteries using tetramethylammonium hydroxide pentahydrate
Solid State Ionics, 1992Co-Authors: Nobuhiro Kuriyama, Hiroshi Miyamura, Tetsuo Sakai, Hiroshi IshikawaAbstract:Abstract A new solid electrolyte, tetramethylammonium hydroxide pentahydrate, was applied to a nickel oxyhydroxide-Metal Hydride (NiOOH/MH) battery and a manganese dioxide-Metal Hydride (MnO 2 /MH) battery, which were prepared by impregnating the melt of the solid electrolyte into the battery components. The NiOOH/MH and MnO 2 /MH batteries were dischargeable even at 10 mA cm −2 and 2 mA cm −2 , respectively. No appreciable decrease in discharged capacity for both batteries was observed up to 200 cycles. Both batteries showed poor charge retention performance, resulting from the decreased density of the oxidized Metal ions near the surface of the active material particles on their positive electrodes due to diffusion of protons and conduction of electrons.
Hatem Ben Mâad - One of the best experts on this subject based on the ideXlab platform.
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Numerical investigation of high temperature Metal Hydride water pumping system
International Journal of Hydrogen Energy, 2019Co-Authors: Faouzi Askri, Amel Miled, Sofiene Mellouli, Hatem Ben MâadAbstract:Abstract I n the present work, a high temperature Metal Hydride Water Pumping System (MHWPS) equipped with a latent heat exchanger was investigated numerically. The operating concept of the pump was presented and the mathematical model of heat and mass transfer within the pump was established. We simulated the pump under different operating conditions using the alloy Mg2Ni as a Metal Hydride and the KNO3 as a Phase Change Material (PCM). The obtained results have shown that i) the developed numerical model is flexible and accurate in predicting the dynamic behavior of the pump ii) the numerical model without radiative heat transfer gives results with errors that can reach 38%, particularly for pumping time iii) the integration of the PCM provides a reduction in the pumping time of about 90% and an increase of the efficiency of the pump of about 7.6 times compared to the case without PCM which represents an improvement of 86% and iv) the Mg2Ni alloy requires high temperature and a mass of PCM about 9 times larger than the case of LaNi5 alloy to pump a volume 6.5 times greater than that pumped with LaNi5.
Tetsuo Sakai - One of the best experts on this subject based on the ideXlab platform.
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hydrogen storage alloys with puni3 type structure as Metal Hydride electrodes
Electrochemical and Solid State Letters, 1999Co-Authors: Jun Chen, Hiroyuki T Takeshita, Nobuhiro Kuriyama, Hideaki Tanaka, Tetsuo Sakai, Masatake HarutaAbstract:A powder sintering method was used to synthesize the interMetallic compounds , , , and . The microstructure and primary phases were observed by scanning electron microscopy and X‐ray diffraction. The pressure‐composition isotherms showed that all alloys could reversibly absorb and desorb up to hydrogen at and a hydrogen pressure of . The sintered samples were employed as the active materials of Metal Hydride electrodes. The Hydride stability and electrochemical performance, combined with low cost raw materials, make these compounds attractive for Metal Hydride electrodes. ©2000 The Electrochemical Society
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Optimization of Fabrication Conditions of Metal-Hydride Electrode Rechargeable with Hydrogen Gas
Hydrogen Power: Theoretical and Engineering Solutions, 1998Co-Authors: Nobuhiro Kuriyama, Hiroyuki T Takeshita, Itsuki Uehara, Hideaki Tanaka, Tetsuo Sakai, T IwasakiAbstract:An air-Metal Hydride (Air-MH) battery has been studied as one of energy conversion systems with a high energy density for electric vehicles (theoretical capacity: 458 Wh-kg-1 for Air-LaNi5H6) [1,2]. The Metal-Hydride negative electrode of this battery is recharged by exposing it to hydrogen gas (H2-recharge), and also electrochemically recharged by use of an additional electrode for oxygen evolution. Therefore the Air-MH battery is suitable for the use in the future community in which both hydrogen gas and electricity are available. We have developed a Metal Hydride electrode for this battery, and showed that the electrode was recharged with hydrogen gas at the rate comparable to usual electrochemical recharging [3].
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electrochemical impedance and deterioration behavior of Metal Hydride electrodes
Journal of Alloys and Compounds, 1993Co-Authors: Nobuhiro Kuriyama, Hiroshi Miyamura, Itsuki Uehara, Tetsuo Sakai, Hiroshi Ishikawa, Toshikatsu IwasakiAbstract:Abstract Electrochemical impedance spectroscopy (EIS) was applied to Metal Hydride electrodes. Cole-Cole plots for the electrodes consisted of two obvious semicircles and a slope related to Warburg impedance. The semicircle in the high-frequency region was mainly related to the resistance and capacitance between the current collector and the pellet of alloy powder. The semicircle in the low-frequency region, which exhibited appreciable dependence on hydrogen content, was attributed to electrode reactions on the alloy particles and double-layer capacitance on the alloy particles. Resistance and capacitance between alloy particles in the electrodes also need to be taken into account. Deterioration processes of Metal Hydride electrodes using a mischMetal-based alloy, MmNi 3.5 Co 0.7 Al 0.8 , were also studied employing EIS. Deterioration of a Metal Hydride electrode using copper-coated alloy powder was dominated by a decrease in reactivity of the alloy surface. In contrast, an increase in the contact resistances and a decrease in the amount of electrochemically utilizable alloy particles were significant in the deterioration of electrodes using uncoated alloy powder. Deterioration of the electrodes was avoided to some extent by elevating the hot-press temperature during electrode preparation.
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Nickel-Metal Hydride battery for electric vehicles
Journal of Alloys and Compounds, 1993Co-Authors: Tetsuo Sakai, Hiroshi Miyamura, Nobuhiro Kuriyama, Itsuki Uehara, U. Kajiyama, Mariko Muta, A. Takagi, K. Kinoshita, F. IsogaiAbstract:When a nickel-powder-mixed alloy electrode using MmNi3.5Co0.7Al0.8 (Mm = mischMetal) was held in a complete discharge state at 40 °C, a severe capacity decrease due to passivation was observed. This capacity lowering was prevented by a nickel (copper) coating or by a cobalt powder mixing. The alloy MmNi3.8Co0.5Mn0.4Al0.3 did not cause passivation even for the nickel-mixed alloy. Prismatic nickel-Metal Hydride batteries (30–60 A h) were constructed using the alloy electrodes and evaluated as an electric vehicle battery.
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Solid-state Metal Hydride batteries using tetramethylammonium hydroxide pentahydrate
Solid State Ionics, 1992Co-Authors: Nobuhiro Kuriyama, Hiroshi Miyamura, Tetsuo Sakai, Hiroshi IshikawaAbstract:Abstract A new solid electrolyte, tetramethylammonium hydroxide pentahydrate, was applied to a nickel oxyhydroxide-Metal Hydride (NiOOH/MH) battery and a manganese dioxide-Metal Hydride (MnO 2 /MH) battery, which were prepared by impregnating the melt of the solid electrolyte into the battery components. The NiOOH/MH and MnO 2 /MH batteries were dischargeable even at 10 mA cm −2 and 2 mA cm −2 , respectively. No appreciable decrease in discharged capacity for both batteries was observed up to 200 cycles. Both batteries showed poor charge retention performance, resulting from the decreased density of the oxidized Metal ions near the surface of the active material particles on their positive electrodes due to diffusion of protons and conduction of electrons.
