Novel Composite Polymer Electrolytes of PVdF-HFP Derived by Electrospinning with Enhanced Li-Ion Conductivities for Rechargeable Lithium–Sulfur Batteries

Composites of poly­(vinylidene fluoride-co-hexafluoro propylene) (PVdF-HFP) incorporating 10 wt % bis­(trifluoromethane)­sulfonimide lithium salt (LiTFSI) and 10 wt % particles of nanoparticulate silica (nm-SiO₂), nanoparticulate titania (nm-TiO₂), and fumed silica (f-SiO₂) were prepared by electrospinning. These membranes served as host matrix for the preparation of composite polymer electrolytes (CPEs) following activation with lithium sulfur battery electrolyte comprising 50/50 (vol %) dioxolane/dimethoxyethane with 1 M LiTFSI and 0.1 M LiNO₃. The membranes consist of layers of fibers with average fiber diameter of 0.1–0.2 μm. CPEs with f-SiO₂ exhibited higher ionic conductivity with a maximum of 1.3 × 10^–3 S cm^–1 at 25 °C obtained with 10 wt % filler compositions. The optimum CPE based on PVdF-HFP with 10 wt % f-SiO₂ exhibited enhanced charge–discharge performance in Li-S cells at room-temperature eliminating polysulfide migration, delivering initial specific capacity of 895 mAh g^–1 at 0.1 C-rate and a very low electrolyte/sulfur (E/S) ratios between 3:1 to 4:1 mL.g^–1. The CPEs also exhibited very stable cycling behavior well over 100 cycles (fade rate ∼ 0.056%/cycle), demonstrating their suitability for Li-S battery applications. In addition, the interconnected morphological features of PVdF-HFP result in superior mechanical properties (200–350% higher tensile strength). Higher Li-ion conductivity, higher liquid electrolyte uptake (>250%) with dimensional stability, lower interfacial resistance, and higher electrochemical stability are some of the attractive attributes witnessed with these CPEs. With these improved performance characteristics, the PVdF-HFP system is projected herein as suitable polymer electrolytes system for high-performance Li–S rechargeable batteries

TEQIP - III Sponsored First International Conference on Innovations and Challenges in Computing, Analytics and Security

This book contains abstracts of the various research papers of the academic & research community presented at the International Conference on Innovations and Challenges in Computing, Analytics and Security (ICICCAS-2020). ICICCAS-2020 has served as a platform for researchers, professionals to meet and exchange ideas on computing, data analytics, and security. The conference has invited papers in seven main tracks of Data Science, Networking Technologies, Sequential, Parallel, Distributed and Cloud Computing, Advances in Software Engineering, Multimedia, Image Processing, and Embedded Systems, Security and Privacy, Special Track (IoT, Smart Technologies and Green Engineering). The Technical and Advisory Committee Members were from various countries that have rich Research and Academic experience. Conference Title: TEQIP - III Sponsored First International Conference on Innovations and Challenges in Computing, Analytics and SecurityConference Acronym: ICICCAS-2020Conference Date: 29-30 July 2020Conference Location: Pondicherry Engineering College, Puducherry – 605014, India (Virtual Mode)Conference Organizer: Department of Computer Science and Engineering, Pondicherry Engineering College, Puducherry, India.Conference Sponsor: TEQIP-III NPIU (A Unit of the Ministry of Human Resource Development, India)