摘要
先采用高压静电纺丝技术制备二氧化钛/聚酰胺酸(TiO2/PAA)复合纤维膜,然后对其进行热亚胺化处理制备出二氧化钛/聚酰亚胺(TiO2/PI)复合纤维隔膜。使用扫描电子显微镜(SEM)、傅里叶红外光谱分析仪(FTIR)、热失重分析仪和电化学工作站测试了TiO2/PI复合纤维隔膜的基本性能和电化学性能,结果表明:隔膜具有明显的三维网状结构,与未改性的纯PI隔膜相比,改性后TiO2/PI复合纤维隔膜的拉伸强度、孔隙率和吸液率分别提高到16.74 MPa、77.5%和550%;其热收缩性能较好,整体电化学性能优异。制备的LiFePO4(磷酸铁锂正极)/TiO2/PI/C(石墨负极)电池具有优异的循环稳定性和高放电容量,在1 C条件下进行100个循环后,其库伦效率在25℃和120℃高达96.7%和90.7%。
Ti O2/PAA composite fiber membranes were prepared by high-voltage electrospinning,and then were thermally imidized to obtain TiO2/PI composite fiber membranes.The physical properties,mechanical properties and electrochemical properties of TiO2/PI composite fiber separators were assessed by means of scanning electron microscope,Fourier infrared spectrometer,thermogravimetric analyzer and electrochemical workstation.The results show that the membrane have clear three-dimensional network structure,and the tensile strength,the porosity and the liquid absorption rate of the modified Ti O2/PI composite membrane increase to 16.74 MPa,77.5%and 550%,respectively comparing with the plain PI membrane;the membrane have good thermal shrinkage performance;excellent overall electrochemical performance;the prepared Li-battery of LiFePO4(lithium iron phosphate positive electrode)/TiO2/PI/C(graphite negative electrode)presents excellent cycle stability and high discharge capacity,after 100 cycles at 1 C、at 25°C and 120°C,the cell coulombic efficiency is as high as 96.7%and 90.7%,respectively.
作者
巩桂芬
李泽
王磊
崔巍巍
GONG Guifen;LI Ze;WANG Lei;CUIWeiwei(School of Materials Science and Engineering,Harbin University of Science and Technology,Harbin 150040,China;College of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China)
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2020年第3期169-175,共7页
Chinese Journal of Materials Research
基金
国家自然科学基金(51603075).
