正极添加剂对阀控密封铅酸蓄电池电化学性能的影响

发布时间：2018-01-09 11:19

本文关键词：正极添加剂对阀控密封铅酸蓄电池电化学性能的影响　出处：《安徽工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：铅酸蓄电池被认为是最有前途的车载电源之一,但是正极板容量较低且易软化脱落限制了铅酸蓄电池的发展。本文从正极板栅和正极添加剂入手,以期提高蓄电池放电容量和循环寿命等电化学性能。本文通过放电性能测试、循环寿命测试、循环伏安测试、电化学阻抗测试、塔菲尔曲线测试、X射线衍射仪测试、扫描电镜测试等研究了不同制造工艺对正极板栅电化学性能的影响、不同扫描速度和温度下正极板栅的电化学行为以及碳纤维、亚氧化钛和二氧化硅三种正极添加剂对铅酸蓄电池性能的影响。研究结果表明:520℃炉温、540℃勺温和90℃时效工艺正极板栅更适用于铅酸蓄电池。此工艺正极板栅析氧量较少,Pb在电解液中溶解量较少,蓄电池的深循环性能较好,早期容量衰减也相对较少,并且板栅耐腐蚀性能和导电性能均衡。同时炉温、勺温与时效温度这三者之间存在制约,共同影响板栅性能。另外,板栅各性能之间可能有所对立,板栅工艺需要权衡和兼顾多个方面。正极板栅在高温状态下工作时,析氢量与析氧量均增加,板栅腐蚀速率加快,蓄电池充放电性能提高,容量也增加。碳纤维正极添加剂可以提高蓄电池容量和循环寿命,比表面积较大则效果更好,并且最佳添加量为0.5‰。碳纤维能够细化活性物质颗粒,作用亦比较稳定。少量碳纤维在活性物质中形成的导电网络,能够使电流分布更为均匀,提高极板化成效率和蓄电池放电性能,还可以增强活性物质机械强度,延缓其软化脱落,提高蓄电池的循环性能。此外添加少量碳纤维还能够减少蓄电池的析氢量和析氧量。亚氧化钛正极添加剂可以提高蓄电池放电容量,高倍率放电时亚氧化钛效果更明显,当添加量为5‰时蓄电池容量提高最多,比未添加亚氧化钛的蓄电池容量可提高13%左右。亚氧化钛能够提高正极生板中PbO的含量,细化极板颗粒,并使颗粒大小更为均匀。SiO2正极添加剂可以提高蓄电池放电容量。常温下SiO2添加量为3‰时蓄电池放电容量提高最多,在3C倍率放电时容量可提高约7.5%。在低温时,SiO2添加量为5‰对蓄电池容量最有利,比未添加SiO2的试验电池可提高约12%。二者不一致的原因应是蓄电池高倍率放电和低温放电机理有所不同。SiO2添加量分别为3‰和5‰的正极生板PbO含量约高达40%,并且极板颗粒松紧程度适宜,既利于电极反应进行又维持了颗粒间的结合力。
[Abstract]:The lead-acid battery is considered to be one of the most promising vehicle power supply, but the positive plate of low capacity and easy softening and shedding limits the development of lead-acid battery. The positive grid and cathode additives to start, in order to improve the battery discharge capacity and cycle life of the discharge. The electrochemical performance test, cycle life test. Cyclic voltammetry, electrochemical impedance spectroscopy, Tafel curve test, the test of X ray diffraction, scanning electron microscopy to study the influence of different processes on the electrochemical performance of anode grid, the electrochemical behavior of anode grid and carbon fibers with different scanning speed and temperature effect of titanium suboxide silica and three kinds of positive additives on performance of lead-acid the battery. The results show that: 520 DEG C temperature 540 C, 90 C the mild aging process of positive plate is more suitable for the process of lead-acid battery. Positive grid of less oxygen, less the amount of Pb dissolved in the electrolyte, the battery deep cycling performance is better, PCL is relatively small, and the grid corrosion resistance and conductivity of equilibrium. At the same time there are constraints between the temperature, temperature and aging temperature of the three, together with the influence of grid performance. In addition, there may be conflict between grid performance, grid technology and many aspects need to weigh both. Positive grid work in the condition of high temperature, hydrogen and oxygen evolution rate increased, grid corrosion speed, improve the battery charge and discharge performance, the capacity is increased. The positive additive of carbon fiber can improve the battery capacity and cycle life, better than the large surface area of effect, and the optimum dosage was 0.5 per thousand. Carbon fiber can refine the active material particles, were relatively stable. A small amount of carbon fiber conductive network formed in the active material That can make the current distribution is more uniform, improving plateformation efficiency and battery discharge performance, but also can enhance the mechanical strength of active substances, delay the softening and shedding of battery, improve cycling performance. In addition to add a small amount of carbon fiber can also reduce the amount of hydrogen battery and oxygen. The positive additive can improve the battery discharge capacity of titanium suboxide. The high rate discharge when the titanium suboxide effect is more obvious, when the adding amount was 5 per 1000 battery capacity up, than the battery capacity without adding titanium suboxide can increase about 13%. The content of titanium suboxide can high polar plate PbO, refining plate particles, and the particle size is more uniform.SiO2 cathode additives can improve the battery discharge capacity at room temperature. The amount of SiO2 is 3 when battery discharge capacity of up to 3C, the discharge capacity can be increased by about 7.5%. at low temperature, S The dosage of iO2 was 5 per thousand in the most favorable to the battery capacity than the test battery without the addition of SiO2 can be increased by about 12%. two is not the same reason should be the battery discharge and discharge mechanism of different amount of.SiO2 were positive in 3 per thousand and 5 per thousand students in PbO were around 40%, and the elastic plate particles the suitable degree, is conducive to the electrode reaction and maintain the binding force between particles.

【学位授予单位】：安徽工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM912

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