采用聚电解质改性的TiO2纳米粒子与聚电解质复合对聚偏氟乙烯(PVDF)多孔膜进行杂化改性，制备了PVDF/聚电解质-TiO2杂化复合膜，考察了改性前后复合膜的界面阻抗与离子电导率变化及其作为锂离子电池隔膜的充放电性能。结果表明， PDDA与TiO2 纳米粒子杂化改性的PVDF复合隔膜的电化学性能优于PVDF原膜，其界面阻抗由原膜的114.5Ω下降至96.9Ω，离子电导率由原膜的1.61×10-4 S/cm升高至3.12×10-4 S/cm，且采用该复合隔膜组装的锂离子电池在0.2C倍率下充放电循环100圈后，放电比容量保持率为75.5 %。

The PVDF porous membrane was coated by the hybrid of polyelectrolyte and the modified TiO2 nanoparticles for using as lithium-ion battery separator. The variation of interface impedance, ionic conductivity and the electrochemical property of PVDF membrane before and after modification were investigated respectively. The results showed that the electrochemical performance of the modified PVDF/PDDA-TiO2 separator was obviously improved comparing with that of PVDF pristine membrane. The ionic conductivity of the PVDF/PDDA-TiO2 separator increased from 1.61×10-4 S/cm to 3.12×10-4 S/cm, while the interface impedance decreased from 114.5 Ω of the pristine PVDF separator to 96.9 Ω of the PVDF/PDDA-TiO2 separator. When the separator was assembled into lithium-ion battery, the discharged specific capacity was 75.5% after 100 cycles at 0.2C ratio.

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