3D poly(vinylidene fluoride–hexafluoropropylen) nanofiber-reinforced PEO-based composite polymer electrolyte for high-voltage lithium metal batteries

• Published in: Electrochimica acta 2022-02, Vol.404, p.139769, Article 139769
• Main Authors: Yao, Zhongran, Zhu, Kongjun, Li, Xia, Zhang, Jie, Chen, Jiatao, Wang, Jing, Yan, Kang, Liu, Jinsong
• Format: Article
• Language: English
• Subjects: Cycling stability; Dendritic structure; Electrochemical window; Electrolytes; Electrolytic cells; Energy storage; Fluorides; Flux density; High voltages; Lithium; Lithium batteries; Lithium dendrite; Lithium–metal batteries; Low conductivity; Low voltage; Molten salt electrolytes; Nanofibers; Polymers; Polyvinylidene fluorides; Safety; Solid electrolytes; Solid state; Solid-state electrolytes; Stability; Storage batteries; Three dimensional composites; Vinylidene fluoride
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2021.139769

•PEO-based 3D CPE-5 was prepared by reinforcing with PVDF-HFP nanofibers and LATP particles.•The thickness of 3D CPE-5 is only 50 μm with excellent mechanical strength.•3D CPE-5 displays high electrochemical window (5.21 V) and lithium transference number (0.49).•3D CPE-5 shows excellent stability to Li-metal and effective lithium dendrite inhibition.•High-voltage Li/3D CPE-5/NCM811 battery shows excellent cycling stability at 0.1 and 0.5 c. Solid-state lithium metal batteries (SSLMBs) are considered as a promising energy storage technology due to their high energy density and safety. However, the relatively low conductivity of solid-state electrolytes and the high electrolyte–electrode interfacial resistance seriously limited the development of SSLMBs. In this work, the high-performance PEO-based composite polymer electrolyte (3D CPE-5) was successfully prepared by reinforcing with polyvinylidene fluoride–hexafluoropropylene nanofibers and Li1.3Al0.3Ti1.7(PO4)3 (LATP) particles. The thickness of 3D CPE-5 is only 50 μm with high electrochemical window (5.21 V) and lithium transference number (0.49) at 60 ℃. In addition, the 3D CPE-5 shows excellent stability to Li–metal, so that Li–Li symmetric cells can run stably for more than 300 h under 0.1 mA cm−2 with low voltage polarization value (15 mV) and effective lithium dendrite inhibition. Finally, the high-voltage Li/3D CPE-5/NCM811 (LiNi0.8Co0.1Mn0.1O2) solid-state battery demonstrates excellent cycling stability at 0.1 and 0.5 C (60 ℃). The excellent safety performance of 3D CPE-5 highlights its remarkable advantages over liquid electrolytes and provide an effective design strategy of high-performance polymer electrolytes for SSLMBs. [Display omitted]