【作者】 刘圣迁；

【导师】 刘建华；

【作者基本信息】 天津大学 ， 应用化学， 2003， 硕士

【摘要】 作为二十一世纪理想的绿色环保电源，锂离子电池有着十分广阔的应用前景，目前国外对锂离子电池的研究和开发都给予了极大的关注。随着人们研究的深入，其种类也日趋多元化。液态软包装锂离子电池采用与液态锂离子电池相似的液态电解液做为锂离子在正负极之间传输的介质，而电池壳体则采用聚合物锂离子电池用的铝塑复合膜，它具有质量轻，工艺简单，外形设计灵活方便，成本低等特点，是一种新型的锂离子电池产品。本论文研究了制造液态软包装锂离子电池的工艺，对工艺研究中出现的技术难点进行了深入分析。重点研究了负极材料预处理、包装材料的优选、电池封装工艺、加液量及化成制度对液态软包装锂离子电池的性能影响。考察了053048型成品液态软包装锂离子电池的各项电化学性能及安全性能。对经过不同充放电循环次数的石墨电极作界面交流阻抗图谱，得出负极上SEI膜主要在电池首次循环中形成；运用气相色谱分析电池首轮循环产生的气体，表明负极表面SEI膜形成时会伴随着电池的气胀及不可逆容量损失。针对此问题确定了以化学方法在天然石墨表面沉积上含有磷化物、铬化物的材料，形成类似于SEI膜的阻化膜的石墨预处理方法。此方法处理的石墨与未处理的石墨及表面镀金属层改性、高温氧化改性的石墨比较，电池首次不可逆容量损失减少，气胀程度得到改善，循环稳定性及倍流充放电能力也有较大提高。根据液态软包装锂离子电池生产的实际要求，研究制定出了铝塑复合膜性能测定技术及标准，优选出一种基本结构为六层、总厚度为113μm的铝塑复合膜，依照此复合膜的材料、结构及性质确定了以冲壳成型技术和热板粘结技术为主的电池封装技术，并利用加气室的方法从封装工艺上解决了电池首轮循环气胀问题。通过研究电池容量、内阻与加液量的关系以及不同加液量电池的容量分布情况，确定了053048型液态软包装锂离子电池的精确加液量为2.2g。比较常规化成制度及改进化成制度，以CC恒流化成，能使电池得到很好的活化，并减轻气胀对电池性能的影响。对053048型液态软包装锂离子电池进行性能检测，0.2C5、0.5C5、1C5三种倍率放电容量均在500mAh以上，3.6V放电电压平台分别为92.2%、86.1%、75.8%，循环寿命达300次以上，容量衰减率小于10%。其环境适应性能、高低温性能、自放电性能及安全性能均达到或超过了国标（GB/T 18287-2000）水平。更多还原

【Abstract】 At the present time lithium-ion batteries as protective environment electrical source in 21 century have been drawn close attention because of their wide application prospect. Liquid state soft-package lithium ion battery is a new-style lithium ion battery. It’s electrolyte is liquid as liquid state lithium ion batteries and the crust is Al compound packing film as polymer lithium ion battery. Liquid state soft-package lithium ion battery has many excellent characteristics including light weight、simple technics、flexible shape design、low cost and so on.In the article, the manufacture technology of liquid state soft-packing lithium-ion battery was introduced, and the difficulties in the technics research were amply studied. Treatment of the material of cathode, choose soft packing material, technics of encapsulation, electrolyte content and activation that affect performance of batteries were emphasized. Also, we tested the varied electrochemical performance and the security of 053048 type liquid state soft-package lithium ion batteries.Impedance spectra of graphite with different cycles showed that SEI film formatted in the first cycle, and the gas chromatography of internal gas of batteries showed that batteries generated gas and lost capacity with formation of SEI. So, put the phosphide and chromate deposited on the graphite to instead SEI, can reduce the losing of capacity and gas generation.According to the require of liquid state soft-package lithium ion batteries, one kind of Al compound packing film which has six layer and 113μm thickness was chose. The film determined we adopting Cup forming technology and hot plate adhesive method for encapsulation of battery. In addition, we resolved the gas generation in first cycle by improving the technics of encapsulation.To the 053048 type batteries, the best electrolyte content is 2.2g, and the best activation is CC constant current mode. The test results showed that discharge capacities at 0.2C5、0.5C5、1C5 were all beyond 500mAh, and the discharge flats on 3.6V were respectively 92.2%、86.1%、75.8%. Cycle life was 300 times, the attenuation of capacity less than 10%. The performance of adapting environment、high and low temperature、short circuit and self-discharge of battery entirely reached the standard of China.更多还原