Study of Electrical and Electrochemical Behaviour on Hot-press Synthesized Nano-Composite Polymer Electrolyte (NCPE) Membranes: [(70PEO: 30 KNO3) + x SiO2]

• Published in: International journal of electrochemical science 2011-04, Vol.6 (4), p.867-881
• Main Authors: Agrawal, R.C., Mahipal, Y.K.
• Format: Article
• Language: English
• Subjects: hot-press technique; ionic conductivity; ionic transport number etc; Nano-Composite Polymer Electrolyte (NCPE)
• ISSN: 1452-3981; 1452-3981
• DOI: 10.1016/S1452-3981(23)15041-3

Poly (ethylene oxide) (PEO) based Nano-Composite Polymer Electrolyte (NCPE) membranes: (70PEO: 30KNO3) + x SiO2, where x = 0, 1, 2, 3, 5, 8, 10, 12 wt. (%), have been casted by hot-press/ solution free technique. Solid Polymer Electrolyte (SPE) composition: (70PEO: 30 KNO3) (wt. %), reported earlier as highest conducting film with room temperature conductivity (σrt) ~ 3.98 x 10-7 Scm-1, has been used as the Ist – phase host matrix and SiO2 filler particles of nano-dimension (~ 8 nm) as IInd – phase dispersoid. The fractional dispersal of SiO2 filler (viz. x = 5 wt. %) in Ist – phase SPE host resulted into nearly three fold increase in the room temperature conductivity. This NCPE film: (70PEO: 30 KNO3) + 5 SiO2 has been referred to as Optimum Conducting Composition (OCC) NCPE film. Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) techniques have been used to study the morphological, structural, thermal and spectroscopic responses respectively of NCPE OCC film material. The ion transport behaviour has been characterized in terms of basic ionic parameters viz. conductivity (σ), mobility (µ), mobile ion concentration (n) and ionic transport number (tion). The frequency dependent dielectric response has also been studied in the temperature range 303-353 K. The newly synthesized NCPE OCC membrane has been sandwiched between K -metal anode and different cathodes to fabricate all-solid-state battery having following cell configurations: Cell # 1 : K (anode) // NCPE film// C+I2+ Electrolyte (cathode) Cell # 2 : K (anode) // NCPE film// MnO2+C + Electrolyte (cathode) Open Circuit Voltage (OCV) values ~ 2.18 & ~ 2.08, have been obtained for Cells # 1 & # 2 respectively. The cell performance has been studied at room temperature by recording cell potential discharge profiles with time under different load conditions. Some important cell parameters have been evaluated in the plateau region of the discharge profiles.