Paper PS-ThM10
Atmospheric Plasma Synthesis of Nanoparticulates at Low Temperature and Roll-to-Roll Binder-Free Coating on Polyethylene Separator for Lithium Ion Battery with Improved Performances

Thursday, December 6, 2018, 11:00 am, Room Naupaka Salon 5

The roll-to-roll atmospheric pressure plasma synthesis and coating of nanoparticulates at low temperature is the most prominent green technique to fabricate thin film on polymer substrates. It can provide a unique environment for chemical reactions and film growth, which is distinct from the ordinary condensed chemical reaction driven by single hot source. All the reactions are far from chemical equilibrium and take place at low gas temperature. Its vital role have been more and more recongnized in flexible fiber optoelectronic/electronic devices, intelligent wearable technology, lightweight fiber compositese and organic/inorganic functional composite membrane etc..

In the present study, different kinds of non-thermal reactive plasmas of HMDSO/Ar/O2 and TiCl4/Ar/O2 have applied to obtain stable discharge at atmospheric pressure and low temperature. The gas phase dissociation and nucleation process, combination of discharge modes, plasma parameter influences on the TiO2 and SiOxCyHz films have been investigated by optical emission spectrum(OES), field scanning electron microscope (FESEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) etc.. P olyethylene (PE) separator for lithium-ion batteries has been tested to move through a home-made roll to roll plasma reactor and a thin film composed of well limited nanoparticulates (average size is around 100 nm) is directly deposited on its top and internal fiber surface. The nanoparticulates are tightly bound on porous PE separator top and inner surface without any other organic binders. The coated PE separator exhibits improved thermal stability, wettability to electrolyte and electrolyte uptake. LiFePO4 cells assembled with the coated PE separator display better conductivity and cycling performance. To the best of our knowledge, this is the first report on atmospheric plasma roll to roll coating of nanoparticulate film on polyolefin separators for LIBs compatible with its present online manufacture process.