锂电池聚丙烯微孔隔膜孔隙品质提升的研究

Study on Pore Quality Improvement of Polypropylene Microporous Separator for Lithium Batteries

为提升聚丙烯材料锂电池微孔隔膜的孔隙品质,采用干式制作法,通过实验的方法探讨挤出成型最佳的滚轮温度和引取速度,探讨延伸过程的最佳的热延伸速度及热延伸倍率。最后将聚环氧乙烷(PEO)和β成核剂分别以质量分数1%加入聚丙烯(PP)材料中进行对比实验,利用场发射扫描电子显微镜(FESEM)来分析孔洞质量。研究表明,在滚轮温度为90 ℃、引取速度为5 m/min、热延伸速度为200 mm/min和热延伸倍率为100%的条件下,添加1%的β成核剂获得的孔隙质量最佳。

In order to improve the pore quality of polypropylene lithium battery microporous diaphragm,the optimum roller temperature and extraction speed for extrusion forming were investigated by dry fabrication method,and the optimum thermal elongation rate and thermal elongation ratio were also discussed.At last,polyethylene oxide(PEO)and β nucleating agents were added into polypropylene(PP)materials by 1% to conduct comparative experiments,and the quality of the holes was analyzed by field scanning electron microscopy(FESEM).The results show that the pore quality obtained by adding 1%β nucleating agent is the best when the roller temperature is 90 ℃,the extraction speed is 5 m/min,the thermal elongation speed is 200 mm/min and the thermal elongation ratio is 100%.