【作者】 曾佳；

【导师】 史鹏飞；

【作者基本信息】 哈尔滨工业大学 ， 应用化学， 2006， 硕士

【摘要】 本文主要研究工作包括以下几个方面:一是根据混合动力车(HEV)用Ni/MH动力电池控制方面的要求,研究了Ni/MH电池的内压与荷电态的关系。二是研究并制备了5.7Ah的方形Ni/MH电池,并进行了综合性能测试。三是研究了几种不同物质对正极进行表面处理及作为正极添加剂对电池自放电的影响及作用机理。研究发现D型Ni/MH电池在正负极容量配比确定的情况下,电池循环30次之后,Ni/MH电池的内压与荷电态间是存在着一定关系,随着电池荷电态的增大,电池内压线性增加。在相同荷电态下,随着Ni/MH电池正负极容量比的增大,电池内压会逐渐上升,但是非线性的增大。即使当正负极容量比达到1.00:1.00时,电池工作在荷电态30%~80%之间时,内压也一般不超过0.2MPa。对Ni/MH电池脉冲充放电表明,虽然内压会有较大的变化,但只要荷电态相同,并且静置时间够长,电池的内压与荷电态的关系就基本保持不变。由此得出Ni/MH电池应用于混合动力车中,基本可以将电池的内压来作为判定电池荷电态情况的重要参考值。通过对电池欧姆内阻的测量,确定了5.7Ah容量的方形Ni/MH电池的最优的极片尺寸,即正极尺寸120mm×72mm,负极尺寸121mm×72mm。采用此种极片尺寸的方形Ni/MH电池可以有较小的内阻。综合电池性能研究和工艺优化结果,制备了额定容量为5.7 Ah的方形Ni/MH电池,并进行综合性能测试。电池在常温下的容量达到“863”测试规范中的要求;功率测试结果表明电池的功率密度达到国内平均水平。同时积累了对于储氢合金电极热处理的经验。在热处理的过程中,通入还原气体氢气的量及电极离开还原气氛是否完全冷却的状态都对热处理有着较大的影响。主要是要保证在整个热处理的过程中电极不被氧化。通过自制的实验装置研究表明用30mass%和60mass%的PEG溶液对Ni/MH电池正极进行表面处理,可以在对正极容量影响较小的情况下又有效的减少电池的自放电。通过扫描电镜观察发现经过表面处理的电极表面形貌与未经过表面处理的电极的表面形貌有差异。循环伏安测试表明进行过此种表面处理的正极的可逆性能得到改进,同时还提高了正极的析氧过电位及充电效率。而用PVA溶液对正极进行表面处理对电极容量影响较大,用CMC溶液对正极进行表面处理对于抑制电池的自放电效果不够理想。而利更多还原

【Abstract】 The main research work of this paper was illustrated as follows: Firstly, according to the request that controlling aspect of the Ni/ MH motive battery used for HEV, the relationship between inner pressure and state of charge of Ni/MH battery was studied. Secondly, the square Ni/ MH batteries with the capacity of the 5.7 Ah were studied and prepared, and the comprehensive performance test was carried on. Thirdly, several different materials were researched on the influence and function mechanism for carrying on the surface processing and self-discharge of the batteries as the cathode additive.Under certain ratio of positive capacity to negative capacity, the inner pressure presented linear relation to SOC after 30 cycles. Based on this conclusion, the inner pressure can be a parameter or behavior the SOC of Ni/MH directly. Under certain SOC, the inner pressure will increase non-linearly with the increase of the ratio of positive capacity to negative capacity. The inner pressure will not exceed 0.2MPa until the ratio of positive capacity to negative capacity reach 1:1.00 and the SOC range from 30% to 80%. Despite the change of inner pressure during the charge period, the inner pressure will present the same function to the SOC after enough displaying time. The inner pressure during charge period and discharge period will rise suddenly with the increasing of temperature. Based on above analysis, it can be concluded that the inner pressure can be used to determine the SOC of Ni/ MH battery in HEV.By testing the battery resistance, we chose the dimension of the square Ni/MH battery of the 5.7Ah capacity as follow: the size of positive was 120mm×72mm,and the size of negative was 121mm×72mm, which presented the low resistance. At room temperature, the experimental shows that, the square Ni/MH battery of the 5.7Ah met the capacity request of“863”, and the power density achieved the local average level. At the same time, the experience of hot processing of MH alloy shows that, the key factor determine the oxidation of alloy were the amount of hydrogen during hot processing and the cool state when the alloy come out of the hydrogen atmosphere.The research based on self-designed experiment device shows that the更多还原