Structural, electrical and electrochemical studies of ionic liquid-based polymer gel electrolyte using magnesium salt for supercapacitor application

Abstract

In the present studies, the effect of ionic liquid 1-Ethyl-2,3-dimethylimidazoliumtetrafluoroborate (EDiMIM)(BF4) on ionic conductivity of gel polymer electrolyte using poly(vinylidene fluoride-co-hexafluoropropylene) [PVdF(HFP)] and magnesium perchlorate [Mg(ClO4)2] as salt was investigated. The maximum room temperature ionic conductivity for the optimized system was found to be of the order of 8.4 × 10–3 S cm−1. The optimized composition reflects Vogel-Tammann-Fulcher (VTF) behavior in the temperature range of 25 °C to 100 °C. The X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy studies confirm the uniform blending of ionic liquid, polymer, and salts along with the enhanced amorphous nature of the optimized system. Dielectric and modulus spectra studies provide the information of electrode polarization as well as dipole relaxation properties of polymeric materials. The optimized electrolyte system possesses a sufficiently large electrochemical window of the order of 6.0 V with stainless steel electrodes.

Effect of Glycerin on Electrical and Thermal Properties of PVA/Copper Sulphate Gel Polymer Electrolytes

“…4. Because of the interaction between the plasticized polymer polar groups and the cations from the salts, there are more ion-conducting sites and a better interfacial contact, resulting in a higher ionic conductivity for the electrolyte [19,22]. Metal ions from salts interact with each other and polar groups (-OH) of polymers by electrostatic interactions, resulting in the formation of coordinating bonds [17,23].…”

“…The ions are capable of migrating in the direction of the electric eld, but due to the blocking electrodes in the low frequency area, they are unable to reach the external circuit, resulting in a dispersion with large ε′ values. As a result, ions become trapped along the electrode-electrolyte contact, forming an electrode polarization layer [ 22,26]. This indicates that electrode polarization and space charge effects are dominant in the low frequency region.…”

“…Similarly, introducing high conducting salts reduces the glass transition temperature (Tg) of the polymer system (as would be stated in DSC data) [14,28]. As a result, crystallinity will decrease and salt dissociation capacity will increase, resulting in enhanced charge carrier transport and greater ionic conductivity [22,28].…”

Amelioration of ionic conductivity (303 K) with the supplement of MnO2 filler in the chitosan biopolymer electrolyte for magnesium batteries

“…Many strategies have been reported utilizing ller and other additives such as plasticizers, ionic liquids, blending and copolymerization for enhancing the physical and electrochemical properties of the polymer electrolytes for magnesium batteries [7,8]. Very recently Ashih Gupta and his co-workers studied the effect of 1-Ethyl-3-methylimidazolium tetra uoroborate (EMIMBF 4 ) ionic liquid on the structural and electrochemical properties of poly (vinylidene uoride-hexa uoropropylene) (PVDF-HFP) utilizing Mg (ClO 4 ) [9]. The addition of ionic liquid depressed the crystallinity in the polymer matrix thereby enhancing the ionic conductivity upto 8.3 х 10 − 3 S cm − 1 .…”

Vanadium oxide nanorods as an electrode material for solid state supercapacitor

“…polyvinyl alcohol (PVA), polyvinylidenefluoride-co-hexafluoropropylene (PVdF-HFP), polyethylene glycol (PEG) etc.) [33][34][35] . GPEs are attractive for energy storage applications due to their high ionic conductivity and electrochemical stability which are comparable to liquid electrolytes, in addition to the fact that GPE also offers dual functions, it can act as an electrolyte and also as a separator 36 .…”