摘要
以N,N-二甲基-甲酰胺(DMF)为溶剂,采用直接挥发法制备无纺布增强型聚偏氟乙烯-六氟丙烯(PVDF-HFP)聚合物电解质,并以锂为负极制备了聚合物电池。用扫描电子显微镜、交流阻抗和循环伏安对所制聚合物膜性能进行了表征,用充放电实验对所制聚合物电池电化学性能进行了测试。实验结果表明,直接挥发法制得的聚合物膜孔穴丰富,微孔呈蜂窝状,吸液率为280%,电化学稳定窗口为4.5V,浸取电解液后室温离子电导率为1.5mS/cm;以LiCoO2为正极制得的聚合物电池0.1C充放电,放电平台为3.9V左右,首次放电容量为137.5mAh/g,20次循环后容量保持在134mAh/g以上,充放电库仑效率高于95%,0.5C放电时放电平台为3.7V,0.5和1C放电分别能保持0.1C放电容量的96%和93%。
A polymer electrolyte based on poly（vinylidene） fluoride-hexafluoropropylene （PVDF-HFP） was prepared by evaporation solvent of dimethyl formamide （DMF）, and the polymer electrolyte was reinforced by nonwoven fabrics. Lithium-ion polymer batteries were assembled by using LiCoO2 as cathode material. The polymer mambrane＇s morphologies and its electrochemical properties were studied by scanning electron microscopy, ac impedance and cyclic voltammetry test. Experimental results show that： this polymer membrane has rich microporous and exhibits 280% uptake of electrolyte solution. The electrochemical stability window of this polymer electrolyte is 4.5V, and its ionic conductivity at room temperature reaches 1.5mS/cm. The polymer Lithium battery displays an initial discharge capacity of 137.5mAh/g and discharge plateau of about 3.9V at 0.1 current rate. After 20 cycles, its discharge capacity is 134mAh/g, and coulombic efficiency is above 95%. When discharging at 0.5C, the voltage plateau is still 3.7V. The discharge capacity of 0.5 and 1C is 96% and 93% of the discharge capacity of 0.1C, respectively.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2006年第9期1401-1403,1407,共4页
Journal of Functional Materials
基金
国家高技术研究发展计划(863计划)资助项目(2003AA32X010)
