【作者】 孙雪梅；

【导师】 高立军；

【作者基本信息】 苏州大学 ， 材料物理与化学， 2015， 硕士

【摘要】 铅酸电池自1859年发明至今已有150多年的历史,是一种工艺成熟、应用广泛的电池技术,从富液电池发展到阀控密封电池,被广泛的应用于通信后备电源、动力电池和汽车启动等领域。但铅酸电池在高倍率部分荷电下(high rate parte state of charge,HRPSo C)的循环使用条件,受到严重的挑战,在HRPSOC循环使用过程中会造成负极不可逆硫酸化,从而影响其在混合动力汽车、风能、太阳能等新领域作为储能装置的利用。20世纪90年代,第三代铅酸电池-铅炭电池(包括超级电池)出现在人们的视野,并成为研究的热点。本论文中,通过大量资料的调研发现,以泡沫碳作为基底,通过脉冲电镀的方法制备二氧化铅薄膜并和活性炭(AC)组装成超级电容器,期望结合铅酸电池和传统超级电容器的优点,来实现其在混合动力汽车、电动汽车等领域的应用。本论文主要的研究内容为:1.通过材料表征手段对AC的一些物理性能进行初步的了解,接着研究其在不同基底和不同电解液中的电化学性能。通过循环伏安、恒流充放电和电化学阻抗谱等方法,研究了其作为超级电容器材料的一些电容特性,为后续的研究奠定一些理论基础。2.采用脉冲电镀的方法,在泡沫碳基底上进行电沉积二氧化铅薄膜,并通过XRD和SEM对电沉积层进行结构和表面形貌的分析。研究发现,电镀液温度、占空比以及酸碱度都对二氧化铅电镀层有一定的影响,在保持占空比不变的情况下,60℃下得到的镀层晶粒较小,这是因为温度升高可以降低阴极的极化,促进形成粗晶的镀层;占空比对不同材料有不同的影响,二氧化铅镀层晶粒的大小随关断时间延长而减小;而酸碱度则会影响晶型的形成,酸性条件下得到的为β(四方晶型)二氧化铅,碱性条件下得到的则是α(正交晶型)二氧化铅;商业二氧化铅通过传统制作电池的方法进行电极的制备,并和电沉积二氧化铅薄膜电极进行对比。通过循环伏安法和交流阻抗研究发现,在酸性镀液下温度为60℃、占空比为25%、电流密度为0.1A/cm2时得到的二氧化铅薄膜电化学性能最为优越。3.采用泡沫碳作为集流体,通过循环伏安、恒流充放电、交流阻抗等方法研究了Pb O2/H2SO4/AC超级电容器的电化学性能。研究发现,在电流密度为200 m A/g时电容为92 F/g,当电流密度为800 m A/g时电容仍有80 F/g,在200m A/g电流密度下循环8000次,电容可保持85%,表现出较好的电化学性能。更多还原

【Abstract】 Lead acid batteries have more than 150 years of history since its invention in 1859. This well-developed energy storage technology has been attracted a lot of interest since the various applications in emergency back-up power source, power battery, and electric vehicle. However, this technology faces serious challenge under high rate parte state of charge(HRPSo C) due to the irreversible sulphating process during the cycling, therefore limiting its employment as energy storage system in the field of clean energy, such as hybrid electric vehicle, wind energy, and solar energy. The super-battery as the third generation lead-carbon battery, has been extensively studied since the performances since 1990. In this thesis, super-capacitor(SC) has been fabricated based on carbon foam as substrate. A thin film of Pb O2 as anode is deposited on a carbon foam substrate using pulse electrodeposition method, and then combined with activated carbon(AC) to form a supercapacitor. This research aims to realize the applications in hybrid and electric vehicles by combining the advantage of lead-acid battery and super-capacitor. The main topics in this thesis include:1. The physical and electrochemical properties of AC have been characterized in detail on different substrates and in electrolytes with cyclic voltammetry, constant current charging-discharging, and electrochemical impedance spectroscopy. These study are the basis of novel electrode materials.2. A lead dioxide thin film was deposited on carbon foam substrate by the pulse electrodeposition method, and the structure and surface morphology were characterized using Xray diffraction(XRD) and scanning electron microscopy(SEM). It is clear that the quality of film was affected by the temperature, duty ratio, and p H value. A film with rough crystalline structure is formed when the temperature increasing to 60℃ and duty ratio keeping constant, since the polarization of the electrode significantly reduced. The variation of duty ratio has different influences on various materials, when prolonging the turn-off time the size of form Pb O2 crystalline grain was reduced. p H value influencing the crystal structure of the formed material. A tetragonal(β) and orthorhombic(α) configuration could be obtained in an acidic and alkaline condition, respectively. Under condition of 60℃, 25% duty ratio, acidic and current density of 0.1 A/cm2,the electro-deposition sample showed a better performance.These results are compared with a commercial lead dioxide has been used to produce electrodes using conventional battery preparation method.3. Pb O2/H2SO4/AC super-capacitor with carbon foam as a current collector, has been investigate by cyclic voltammetry, constant current charging and discharging, and electrochemical impedance spectroscopy. The capacitance was at 92 F/g and 80 F/g, when the current density was 200 and 800 m A/g, respectively. More importantly, under a 200 m A/g current density this material still retains more than 85% of its specific capacitance after 8000 continuous charge–discharge cycles.更多还原