To improve the safety performance of lithium-ion batteries, the research of composite separator with high temperature resistance is one of the strategies. Herein, a poly(vinylidene fluoride-hexafluoropropylene)/cellulose/carboxylic titanium dioxide (PVDF-HFP/cellulose/C-TiO₂) composite separator is prepared by the phase inverse method. The composite separator has higher porosity (63.65%) and electrolyte uptake (210.3%) than PP separator, exhibiting good heat resistance that can keep its shape and size under 160 °C for 0.5 h. Additionally, it has a superior ionic conductivity of 1.24–1.49 mS cm⁻¹ and a lower charge transfer impedance at a room temperature, which brings about better cycle and rate performance. Promisingly, the cell assembled with the PVDF-HFP/cellulose/C-TiO₂ composite separator has a high electrochemical working window and a high current charge of ability, and can undergo 10 charge-discharge cycles normally under 120 °C. The PVDF-HFP/cellulose/C-TiO₂ composite separator has promising potentials for high current and voltage charging, which can improve the safety performance of the lithium-ion battery.

中文翻译：

---

锂离子电池用耐高温聚偏二氟乙烯-六氟丙烯/纤维素/羧酸TiO 2复合隔膜

为了提高锂离子电池的安全性能，研究耐高温复合隔膜是其中的策略之一。在此，通过反相法制备聚偏二氟乙烯-六氟丙烯/纤维素/羧酸二氧化钛（PVDF-HFP /纤维素/ C-TiO ₂）复合隔板。复合隔板比聚丙烯隔板具有更高的孔隙率（63.65％）和电解质吸收（210.3％），具有良好的耐热性，可以在160°C下保持0.5小时的形状和尺寸。此外，它具有出色的1.24-1.49 mS cm ^-1离子电导率，并且在室温下具有较低的电荷转移阻抗，从而带来了更好的循环和速率性能。很有可能，该电池与PVDF-HFP /纤维素/ C-TiO组装在一起₂复合隔板具有较高的电化学工作窗口和较高的电流充电能力，并且通常在120°C下可以进行10次充放电循环。PVDF-HFP /纤维素/ C-TiO ₂复合隔膜具有大电流和高电压充电的潜力，可改善锂离子电池的安全性能。