A Highly‐Efficient Composite Separator with Strong Ligand Interaction for High‐Temperature Lithium‐Ion Batteries. Issue 19 (24th July 2018)

• Record Type: Journal Article
• Authors: Waqas, Muhammad; Tan, Chao; Lv, Weiqiang; Ali, Shamshad; Boateng, Bismark; Chen, Wenjin; Wei, Zhaohuan; Feng, Chao; Ahmed, Junaid; Goodenough, John B.; He, Weidong
• Is Part Of: ChemElectroChem. Volume 5:Issue 19(2018)
• Page Start: 2722
• Page End: 2728
• Publication Date: 2018-07-24
• Subjects: Colloids -- high-temperature lithium-ion battery -- materials science -- PVDF-HFP -- thermal stability; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201800800
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: A PVDF‐HFP/colloidal‐TiO2 composite separator is synthesized for high‐temperature lithium‐ion batteries. Incorporation of colloidal TiO2 in the PVDF‐HFP matrix forms a highly‐uniform composite micro‐structure with strong adsorption interactions between TiO2 and PVDF‐HFP due to the presence of citric acid. The strong interactions are giving rise to advantageous mechanical robustness, separator/electrode interface and electrolyte uptake. The separator shows remarkable stability upon thermal treatment at 150 °C. With a high ionic conductivity up to 1.57×10 −3 S cm −1, the LFP/Li cell with PVDF‐HFP/colloidal‐TiO2 composite separator delivers charge‐discharge capacities of 156.95 mAh g −1 (0.1 C) at room temperature and 120.8 mAh g −1 (0.5 C) after annealing cells at 140 °C for 3 hours with a 99 % capacity retention after 100 cycles. The PVDF‐HFP/colloidal‐TiO2 separator demonstrates promising potentials for practical applications in high‐temperature environments. Abstract : Hot in, so hot in here ! By incorporating colloidal TiO2 in PVDF‐HFP, a composite separator is fabricated showing a robust micro‐structure sustaining high‐temperature treatment. LFP/Li batteries based on the PVDF‐HFP/colloidal‐TiO2 separator deliver a charge‐discharge capacity of 156.9 mAh g −1 (0.1 C) at room temperature and 120.8 mAh g −1 (0.5 C) after annealing batteries at 140 °C for 3 hours with a 99 % capacity retention.