LATP改性PVDF-PAN复合隔膜的制备及应用

Preparation and application of LATP modified PVDF-PAN composite membrane

以高离子电导率的固态电解质磷酸钛铝锂[Li_(1.4)Al_(0.4)Ti_(1.6)(PO_(4))_(3),LATP]纳米材料为上下层,聚偏氟乙烯(PVDF)-聚丙烯腈(PAN)纳米纤维隔膜为中间层,制备高界面相容性的LATP改性PVDF-PAN复合隔膜。利用XRD、SEM、热重分析(TG)及充放电测试,对隔膜的性能进行分析。与纯PVDF-PAN纳米纤维隔膜相比,LATP改性PVDF-PAN复合隔膜具有较好的吸液率、热稳定性和电化学性能,起始分解温度可达443℃。组装的锂离子电池以0.2 C倍率在4.2~3.0 V循环300次,容量保持率为96.22%,界面阻抗由25.32Ω降低至14.38Ω,表现出良好的界面相容性。

The titanium aluminum lithium phosphate[Li_(1.4)Al_(0.4)Ti_(1.6)(PO_(4))_(3),LATP]modified polyvinylidene fluoride(PVDF)-polyacrylonitrile(PAN)composite membrane with high interface compatibility was prepared,using solid electrolyte LATP with high ionic conductivity as top and bottom layers,PVDF-PAN nanofiber membrane as middle layer.The performance of the composite membrane was analyzed by XRD,SEM,thermogravimetry analysis(TG)and charge-discharge test.Compared with pure PVDF-PAN nanofiber membrane,the LATP modified PVDF-PAN composite membrane had better electrolyte affinity,thermal stability and electrochemical performance.The initial decomposition temperature was up to 443℃.The capacity retention rate of the Li-ion battery assembled with it was 96.22%after 300 cycles at rate of 0.2 C in 4.2-3.0 V,the interface impedance was reduced from 25.32Ωto 14.38Ω,demonstrating good interface compatibility.