Biomimetic PVDF/LLTO composite polymer electrolyte enables excellent interface contact and enhanced ionic conductivity

• Published in: Applied surface science Vol. 541; p. 148434
• Main Authors: Li, Boyu, Su, Qingmei, Yu, Lintao, Liu, Wuyou, Dong, Shijia, Ding, Shukai, Zhang, Miao, Du, Gaohui, Xu, Bingshe
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2021
• Subjects: Bio-inspiration; Cellular surface; Composite polymer membrane; Flexible lithium batteries; Mechanical property; Bio-inspiration; Cellular surface; Composite polymer membrane; Flexible lithium batteries; Mechanical property
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2020.148434

[Display omitted] •The bio-inspired PVDF/LLTO-CPEs are fabricated through simple evaporation strategy.•The special design creates cellular structures on the surface of PVDF/LLTO-CPE.•The ultrathin PVDF/LLTO-CPE dhows a high mechanical strength of 10 Mpa.•The full battery delivers an excellent performance under folding and bending states. Composite polymer electrolyte (CPE) with enhanced ionic conductivity, excellent flexibility and strong strength are urgently required for all-solid-state lithium metal batteries (LMBs). Inspired by the dragonfly wings that are super-lightweight and ultrathin but have excellent stability when subject to bending and twisting during flapping, we have constructed Li0.35La0.55TiO3 (LLTO) nanowires-filled polyvinylidene fluoride (PVDF). In our design, the PVDF is used to construct the ultrathin membrane, the 1D LLTO nanowires are acted as the veins to give rise to a high mechanical strength of 10 Mpa. The special design creates cellular surface of PVDF/LLTO-CPE, which guarantees the excellent flexibility as well as a good interface contact between CPE and Li anode. When evaluated as electrolyte for LiFePO4|Li battery, the PVDF/LLTO-CPEs can suppress Li dendrites growth, and thus presents an excellent cycling stability of 140 mAh g−1 after 200 cycles. Moreover, the flexible LiFePO4|PVDF/LLTO-CPE|Li4Ti5O12 pouch cell delivers a satisfactory rate performance and cycle stability under folding and bending states. The excellent performances are attributed to the unique cellular structure and super mechanical strength of biomimetic PVDF/LLTO-CPE. All results show the PVDF/LLTO-CPE is a promising solid-state electrolyte for flexible electronic devices.