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Xiaofeng Zhang Miklos Lengyel Richard L. Axelbaum 《American Institute of Chemical Engineers》2014,60(2):443-450
Nanostructured lithium‐manganese‐rich nickel‐manganese‐oxide xLi2MnO3·(1‐x)LiNi0.5Mn0.5O2 (0.3 ≤ x ≤ 0.6) composite materials were synthesized via spray pyrolysis using mixed nitrate precursors. All the materials showed a composite structure consisting of Li2MnO3 (C2/m) and LiNi0.5Mn0.5O2 components, and the amount of Li2MnO3‐phase appeared to increase with x, as observed from XRD analysis. These composite materials showed a high‐discharge capacity of about 250 mAhg?1. In the range of x considered, the layered 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 materials displayed the highest capacity and superior cycle stability. Nonetheless, voltage suppression from a layered‐spinel phase transition was observed for all the composites produced. This voltage suppression was dependent of the amount of Li2MnO3 phase present in the composite structure. © 2013 American Institute of Chemical Engineers AIChE J 60: 443–450, 2014 相似文献
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磷酸铁锂正极材料兼具安全性好、容量高且对环境友好等优点,成为目前最具潜力的动力电池正极材料之一。但其较低的电子导电率及离子电导率等缺点也十分明显。主要从磷酸铁锂正极材料本身的性能,包括倍率性能、能量密度、循环寿命和高低温性能方面分析了其实际应用于动力电池的潜力,以及结合国内外锂离子电池正极材料供应商情况简述了目前国内外磷酸铁锂产业化现状和趋势。 相似文献
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Optimum configuration, using a hybrid optimisation model for electric renewable software, and design of a photovoltaic (PV)–diesel–battery hybrid energy system has been proposed to power a facility in the University of Port Harcourt, which is located in the suburb of Port Harcourt city, Nigeria. The configuration of the optimum hybrid system is selected based on top-ranked system configuration, according to the net present cost. An optimal system design delivers the best components alongside appropriate operating strategies to provide the most efficient, reliable cost-effective system possible. The system investigated reduces CO2 emissions by 36.3%/year. This will reduce costs imposed on CO2 emissions by future environmental legislation. The system has a better potential for providing the energy needs of the facility considered in this paper compared with a stand-alone PV–battery system as capital costs are reduced by 55%. Reliability was improved as the diesel generator can provide power as and when it is needed. 相似文献
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The process of neutralization with NaOH, in the presence of Fe(III) salt, of sulphuric acid battery industry wastewater seems to be more suitable than any other process for Pb removal because at the same time, it allows the exploitation of the scavenger action of Fe(III), which is often present in the same wastewater and precipitates as hydroxides. In order to optimize sludge production, a laboratory research study has been carried out to minimize the quantity of Fe(III) to be added. All aspects concerning the chemistry of wastewater have been taken into consideration step by step and discussed. As a result, a process which requires the addition of Fe(III) so that an Fe/Pb ratio, both expressed as ppm, of the order of 0.5 is achieved. The process has been applied to two artificial solutions, characterized by a content of H2SO4 of 1000 and 5000 ppm, respectively, and by 10 ppm of Pb, as well as to five samples of wastewater. The proposed process takes about 1 h to perform: 30 min for neutralization up to pH 8.5–9.5 and Fe(III) addition and 30 min for correction in the 9–9.5 pH range and for flocculation with the help of a polyelectrolyte. The Pb concentration of the treated effluent is below 0.2 ppm. Conditions for Pb removal using only NaOH or Na2CO3 have also been considered. 相似文献
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With the enhancement of consciousness of envi-ronmental protection and the increasing exhaustion ofoil resources,study on electric vehicles(EV)or hy-brid electric vehicles(HEV)are being actively con-ductedin the countries worldwide[1-3].Ni/MHbat-tery is p… 相似文献