oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Thermal behavior simulation of Ni/MH battery
DaHe Li,Kai Yang,Shi Chen,Feng Wu
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0105-7
Abstract: Thermal behavior of overcharged Ni/MH battery is studied with microcalorimeter. The battery is installed in a special device in a microcalorimeter with a quartz frequency thermometer. Quantity of heat and heat capacity of the battery charged at different state of charge (SOC) at different rates are measured by the microcalorimeter. Based on a series of assumputions, heat transfer equation is set up. Expression of heat generation is attained by curve fitting instead of theoretical calculation. Thermal model is used to simulate thermal behavior of the battery in charging period, results of calculation and experiment match very well. The temperature distribution is non-uniform because the poor conductivity limits the heat transfer during charging process. It is difficult to greatly improve the heat conductivity of the battery because it is related to materials inside the battery including electrodes, separators and so on. Therefore, high rate charge should be avoided in actual use. It may cause some damage to the battery.
Thermal behavior simulation of Ni/MH battery

DaHe Li,Kai Yang,Shi Chen,Feng Wu,

科学通报(英文版) , 2009,
Abstract: Thermal behavior of overcharged Ni/MH battery is studied with microcalorimeter. The battery is installed in a special device in a microcalorimeter with a quartz frequency thermometer. Quantity of heat and heat capacity of the battery charged at different state of charge (SOC) at different rates are measured by the microcalorimeter. Based on a series of assumputions, heat transfer equation is set up. Expression of heat generation is attained by curve fitting instead of theoretical calculation. Thermal model is used to simulate thermal behavior of the battery in charging period, results of calculation and experiment match very well. The temperature distribution is non-uniform because the poor conductivity limits the heat transfer during charging process. It is difficult to greatly improve the heat conductivity of the battery because it is related to materials inside the battery including electrodes, separators and so on. Therefore, high rate charge should be avoided in actual use. It may cause some damage to the battery. Supported by the National Key Basic Research and Development Program of China (Grant No. 2002CB211800)
Mg-Ni THIN FILM-A POTENTIAL NEGATIVE ELECTRODE FOR NIKEL-METAL HYDRIDE BATTERY
Mg—Ni THIN FILM—A POTENTIAL NEGATIVE ELECTRODE FOR NIKEL—METAL HYDRIDE BATTERY

LZOuyang[],CYChung[],MQZeng[],HWang[],MZhu[],
L.Z.Ouyang
,C.Y.Chung,M.Q.Zeng,H.Wang,M.Zhu

金属学报(英文版) , 2003,
Abstract: Mg-Ni thin films for nickel-metal hydride (Ni-MH) battery negative electrode were prepared on three different substrates by using magnetron sputtering with compacted Ni and Mg mixture powder. The microstructure of Mg-Ni thin films deposited on the glass and the Ni foil substrate respectively was studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the Mg-Ni thin films were in amorphous structure and the composition of the thin film was homogeneous. Electrochemical measurement show the discharge capacity of the thin film negative electrode deposited on the foam Ni substrate was 284.8mAh/g in 6M alkaline electrolyte and the internal resistance was much lower than that of the electrode prepared by the ball-milled powder during the charge-discharge cycle.
Research on catalysis of sodium-metallochlorophylls in Ni/MH battery
Fang Wang,Feng Wu,Shi Chen,XinPing Qiu
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0435-5
Abstract: The effects of sodium-metallochlorophylls including sodium-iron chlorophyllin, sodium-copper chlorophyllin and sodium-magnesium chlorophyllin on performance of Ni/MH battery were investigated. The results show that sodium-iron chlorophyllin can effectively activate the gases produced during charge in Ni/MH battery, therefore reducing the reduction potential of oxygen and the oxidation potential of hydrogen, and the increased speed of inner pressure of battery is decreased significantly. With the aid of DMol3 software, the activation process of oxygen and hydrogen by sodium- metallochlorophylls was simulated and analyzed. It was found that the catalysis behavior is in agreement with the experimental results, and the activation process also gets a reasonable explanation from the calculated results.
Supercapacitor-battery hybrid energy storage devices from an aqueous nitroxide radical active material
Wei Guo,Sen Xin,MengBo Ji,YuGuo Guo,LiJun Wan
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4575-z
Abstract: A hybrid electrochemical energy storage device was fabricated in aqueous NaOH with the 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) nitroxide radical as the active material, hydroquinone as the counter electrode active material, and an OH -selective separating membrane. The working principle of this device was investigated and it can be considered as a supercapacitor-battery hybrid energy storage system. Device performance was characterized by cyclic voltammetry and galvanostatic charge-discharge testing. When using multi-walled carbon nanotubes (MWCNTs) as electrode support materials, a high pseudo-capacitance of 1280 F g 1 was obtained with the TEMPO nitroxide radical as the active material at a 1 mV s 1 scan rate. This was ~33 times larger than the inherent double layer capacitance of MWCNTs. The electrode material and active material dissolved in solution could potentially be substituted with similar materials. This simple design provides a new approach for fabricating high performance supercapacitor-battery hybrid energy storage devices.
Effect of Electrode Constitution on the Discharge Properties of Ni-MH Battery
Jin GUO,Chonghe LI,Nianyi CHEN,

材料科学技术学报 , 1999,
Abstract: The discharge capacities for Ni-MH batteries with different electrode constitutions are analyzed by chemical pattern recognition method, and some criteria for improving synthetical discharge properties are obtained. The results show that the thickness of positive and negative electrode are significant in influencing the discharge capacities at both of low and high discharge current, the influence of resistance of positive electrode on discharge capacity is less significant compared with other factors in electrode constitution and the effect of electrolyte on discharge capacity at low discharge current is more significant than that at high discharge current.
A comparison of iron phthalocyanine and cobalt porphyrin on the electrochemical catalysis in Ni-MH battery
Fang Wang,Feng Wu,Shi Chen,XinPing Qiu,LiQuan Chen
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-2217-2
Abstract: The effects of iron phthalocyanine (FePc) and cobalt porphyrin (CoPp) on inner pressure and cycle behavior of sealed Ni-MH batteries were investigated in this study. The morphology of battery electrode was observed by SEM. The electrochemical impedance spectroscopy of floating-charge/discharge battery was also measured. Experimental results show that the addition of FePc or CoPp to the alloy electrode is an effective approach to decrease the internal pressure of battery during the process of charge and overcharge. In contrast to CoPp, the battery with FePc exhibits a slower capacity decay and a smaller overpotential at the same charge-discharge rate. As an electrocatalyst, FePc may more effectively speed up the reduction of oxygen, and decrease its reduction potential. As a result, the charge process is accelerated, the gas evolution is reduced and the pulverization of electrode materials is slowed down.
A comparison of iron phthalocyanine and cobalt porphyrin on the electrochemical catalysis in Ni-MH battery
WANG Fang,WU Feng,CHEN Shi,QIU XinPing,CHEN LiQuan,
WANG
,Fang,WU,Feng,CHEN,Shi,QIU,XinPing,CHEN,LiQuan

科学通报(英文版) , 2007,
Abstract: The effects of iron phthalocyanine (FePc) and cobalt porphyrin (CoPp) on inner pressure and cycle behavior of sealed Ni-MH batteries were investigated in this study. The morphology of battery elec- trode was observed by SEM. The electrochemical impedance spectroscopy of floating-charge/dis- charge battery was also measured. Experimental results show that the addition of FePc or CoPp to the alloy electrode is an effective approach to decrease the internal pressure of battery during the process of charge and overcharge. In contrast to CoPp, the battery with FePc exhibits a slower capacity decay and a smaller overpotential at the same charge-discharge rate. As an electrocatalyst, FePc may more effectively speed up the reduction of oxygen, and decrease its reduction potential. As a result, the charge process is accelerated, the gas evolution is reduced and the pulverization of electrode materials is slowed down.
Ni-MH battery modelling for ambient intelligence applications  [PDF]
D. Szente-Varga,D. Horvath,M. Rencz
Computer Science , 2008,
Abstract: Mobile devices, like sensor networks and MEMS actuators use mobile power supplies to ensure energy for their operation. These are mostly batteries. The lifetime of the devices depends on the power consumption and on the quality and capacitance of the battery. Though the integrated circuits and their power consumption improve continually, their clock frequency also increases with the time, and the resultant power consumption seems not to vary, or slightly increase. On the other hand, the properties of batteries are developing much slower, necessitating the optimization of their usage on system level.
Progress of Research on Preparation of Mg-Ni Based Alloy by Mechanical Alloying for Hydride Electrode Materials
机械合金化制备Mg-Ni合金氢化物电极材料的研究进展

QIAO Yu-Qing,ZHAO Min-Shou,ZHU Xin-Jian,CAO Guang-Yi,
乔玉卿
,赵敏寿,朱新坚,曹广益

无机材料学报 , 2005,
Abstract: Mg-Ni based alloy has always been paid much attention as important negative electrode materials for Ni/MH battery. Recent research progress in Mg-Ni based alloy by mechanical alloying for Ni/MH battery hydride electrode materials was reviewed with its focus on the electrochemical performance, micro-structural characteristics, mechanism of hydriding and dehydriding and the main methods in preparation and modification of Mg-Ni based alloy electrodes such as Mg-Ni based binary alloys, ternary alloys, composite alloying and surface modifications. Also the main direction of studies on Mg-Ni based alloy by mechanical alloying for Ni/MH battery negative electrode materials was proposed.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.