An Efficient, Scalable Route to Robust PVDF-co-HFP/SiO2 Separator for Long-Cycle Lithium Ion Batteries

作者：Boateng, Bismark; Zhu, Gaolong; Lv, Weiqiang; Chen, Dongjiang; Feng, Chao; Waqas, Muhammad; Ali, Shamshad; Wen, Kechun; He, Weidong^*

来源：Physica Status Solidi-Rapid Research Letters, 2018, 12(10): 1800319.

DOI：10.1002/pssr.201800319

• lithium ion batteries
• PVDF-co-HFP
• SiO2 nanocrystals
• thermal stability

A highly uniform, heterogeneous-phase composite separator is synthesized by a direct post-solidation process from the mixture of nano-SiO2/acetone monodisperse suspension and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP)/acetone gel, without any organic surfactants. This technique leads to the PVDF-co-HFP/SiO2 composite separator outstanding microstructural uniformity. The incorporation of SiO2 nanoparticles leads to reduced crystallinity (approximate to 27%), enhanced wettability (approximate to 14%), improved electrolyte uptake (approximate to 420%), and enhanced mechanical strength (>14MPa) of the composite separator. These enhanced properties of the separator translate into remarkable LiFePO4/Li battery performance with reduced polarization, a high room-temperature capacity of 165mAhg(-1) at 0.5C, a high thermal dimensional stability (approximate to 4.5% shrinkage after annealing at 160 degrees C for 1h) and 5.2% capacity degradation after 1500 charge/discharge cycles at 2C.

• 出版日期2018-10
• 单位电子科技大学