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1.
Spinel LiSr0·1Cr0·1Mn1·8O4 was synthesised by high temperature solid state method in order to enhance the electrochemical performance. The LiSr0·1Cr0·1Mn1·8O4 (LSCMO) materials were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical tests. The XRD and SEM studies confirm that LSCMO had spinel crystal structure with a space group of Fd3m, and the particle of LSCMO shows irregular shape. The cyclic voltammetry data illustrated that the heavy current charge–discharge performance of LMO was improved by Sr2+ and Cr3+ doping. The galvanostatic charge–discharge of LSCMO cathode materials was measured at 1, 5, 10 and 20 C. The results indicated that LSCMO improved the capacity retention. 相似文献
2.
《Energy Policy》2015
The low price of lead-acid, the most popular battery, is often used in setting cost targets for emerging energy storage technologies. Future cost reductions in lead acid batteries could increase investment and time scales needed for emerging storage technologies to reach cost-parity. In this paper the first documented model of cost reductions for lead-acid batteries is developed. Regression to a standard experience curve using 1989–2012 data yield a poor fit, with R2 values of 0.17 for small batteries and 0.05 for larger systems. To address this problem, battery costs are separated into material and residual costs, and experience curves developed for residual costs. Depending on the year, residual costs account for 41–86% of total battery cost. Using running-time averages to address volatility in material costs, a 4-year time average experience curve for residual costs yield much higher R2, 0.78 for small and 0.74 for large lead-acid batteries. The learning rate for residual costs in lead-acid batteries is 20%, a discovery with policy implications. Neglecting to consider cost reductions in lead-acid batteries could result in failure of energy storage start-ups and public policy programs. Generalizing this result, learning in incumbent technologies must be understood to assess the potential of emerging ones. 相似文献
3.
上海秀派公司坚持自己的技术长项——2.45GHz有源RFID,充分发扬该种RFID的特长,记者采访该公司时了解到了开发方面的很多细节、成功案例和实施经验。我们不但非常推崇该公司的“锲而不舍”的意志,而且还意识到如果秀派公司的成功经验一旦辐射到中国的RFID行业中,一定会把这项在国外诞生的技术更好地植根于中国的土壤,使之更加适合中国的实用环境。 相似文献
4.
A vacuum-annealed La0.6Ca0.4CoO3−x was consecutively oxygenated in air at temperatures decreasing from 800 to 100 °C, and its electrocatalytic activities for oxygen reduction and evolution were then measured as a function of the oxygenation temperature. The valence of Co cation, changing between +2 and +3, was found susceptible to annealing either in vacuum or air. The catalytic activities initially decrease monotonically as the oxygenation temperature was decreased from 800 to 300 °C, as a result of increasing oxygen content, and then rise abruptly with the oxygen reduction activity reaching a maximum at 200 °C and the oxidation activity at 150 °C. X-ray photoelectron spectroscopy analysis indicated that the enhancements by the low-temperature oxygenation involved increased OH coverage and less charged cations at surface. The results clearly reveal the importance of the post-calcination annealing process for optimizing the performance of La0.6Ca0.4CoO3−x in air electrode applications. 相似文献
5.
Lithium-ion batteries are becoming more and more important not only for portable electronic devices, but also in prevision of high power electric vehicles. In such an optic, deep studies regarding all the components of a secondary battery are in development. In this study, high voltage cathode materials have been selected. Crystals with spinel structure have a 3D vacancy pathway suitable for Li-ions transport. The material under study was LiNi0.5Mn1.5O4 doped with magnesium replacing the nickel. Various samples were synthesized via three different routes: a solid-state method, a modified sol–gel method and a xerogel method. The structure and morphology of the powders were analyzed with HRTEM and XRD. Electrochemical tests were also performed. A wide range of particle sizes (from micro to nanosize) was the result of the different synthesis routes. Unfortunately pure materials were not always obtained. The electrochemical tests showed improvement of the material's cyclability, by reducing the particle size. The electrochemical tests further confirmed the existence of a Li1+dMn2−dO4 impurity. The results are quite promising, however, further improvement of the purity of the electrode composition are needed. 相似文献
6.
通过改进铅膏的配方及极板的独特处理工艺 ,提高了干电荷电摩托车电池的低温高率放电性能、充电接受能力和储存性能 ,完全可以满足国内外摩托车主机厂的各种要求。 相似文献
7.
This study provides experimental evidence for proton and hydrogen formation caused by the anodic electropolymerization of cyclohexyl benzene (CHB), which is a popular electrolyte additive for overcharge protection of lithium-ion batteries (LIBs). It is found that considerable H2 evolution is observed in overcharged LiCoO2/graphite cells, especially when CHB is included as an electrolyte additive. In order to confirm the proton generation during the CHB oxidation, Pt/Pt-rotating ring disc electrode (RRDE) measurements are performed in 1 M Li(C2F5SO2)2N ethylene carbonate/ethyl methyl carbonate (1/2, v/v) solutions with and without CHB. The cathodic ring current is intimately correlated to the anodic disc current, and the cathodic reaction at the ring is determined to be the reduction of the proton. The proton generation efficiency during the CHB oxidation is as high as 90%. Proton liberation is also observed during the anodic decomposition of the electrolyte solvents, although it occurs in a much less stoichiometric way compared with that during the CHB oxidation. 相似文献
8.
9.
通信用VRLA蓄电池可靠性指标及计算探讨 总被引:1,自引:0,他引:1
在说明通信局(站)电源系统对VRLA蓄电池组可靠性要求的基础上,阐述了为了达到电信设备的电压、电流需求,通过串联或串并联构成电池组的单体VRLA蓄电池应达到的可靠性指标。在确定单体VRLA蓄电池应达到的可靠性指标。在确定单体VRLA蓄电池可靠性参数时,可通过现场使用调查或加速寿命试验的办法来求得。在单体VRLA蓄电池可靠性指标过低的情况下,可通过多种冗余连接方式来提高电池组的可靠性。 相似文献
10.
常延勋 《电信工程技术与标准化》2002,(2):38-40
该针对阀控密封铅酸蓄电池的特性和使用环境,较全面的论述了接入网点蓄电池的选型要求与维护方式。 相似文献