Lithium ion conduction in extreme polymer in salt regime

An attempt has been made to prepare a new proton conducting polymer electrolyte based on polyvinyl alcohol (PVA) doped with NH 4 NO 3 by solution casting technique. The complex formation between polymer and dissociated salt has been confirmed by X-ray diffraction analysis. The ionic conductivity of the prepared polymer electrolyte has been found by ac impedance spectroscopic analysis. The highest ionic conductivity has been found to be 7.5×10 −3 Scm −1 at ambient temperature for 20 mol% NH 4 NO 3 -doped PVA with low activation energy (~0.19 eV). The temperature-dependent conductivity of the polymer electrolyte follows an Arrhenius relationship, which shows hopping of ions in the polymer matrix.

Section: Dielectric Spectra Analysismentioning

confidence: 93%

Structural and ionic conductivity studies on proton conducting polymer electrolyte based on polyvinyl alcohol

Hema

Selvasekarapandian

Nithya

et al. 2008

“…Electrical conductivity of polyvinyl alcohol (PVA)-based polymer electrolytes have been investigated by many researchers to understand the charge transport behavior in the electrolyte films [1][2][3]. The advantages of PVA are the good film-forming abilities and high mechanical strengths.…”

Section: Introductionmentioning

confidence: 99%

Dielectric and conduction mechanism studies of PVA-orthophosphoric acid polymer electrolyte

Kufian

Majid

Arof

2007

Polyvinyl alcohol (PVA)-based proton conducting polymer electrolytes have been prepared by the solution cast technique. The conductivity is observed to increase from 10 −9 to 10 −4 S cm −1 as a result of orthophosphoric acid (H 3 PO 4 ) addition. The plot of conductivity vs temperature shows that a phase transition occurred at 343 K in the sample PVA-33 wt% H 3 PO 4 . The β-relaxation peak is observed at 313 K. The glass transition temperature of PVA-33 wt% H 3 PO 4 is 343 K. Orthophosphoric acid seems to play a dual role, i.e., as a proton source and as a plasticizer. The ac conductivity σ ac = Aω s was also calculated in the temperature range from 303 to 353 K. The conduction mechanism was inferred by plotting the graph of s vs T from which the conduction mechanism for sample PVA-17 wt% H 3 PO 4 was inferred to occur by way of the overlapping large polaron tunneling (OLPT) model and the conduction mechanism for the sample PVA-33 wt% H 3 PO 4 by way of the correlated barrier height (CBH) model.

“…The complex permittivity reveals the presence of dipoles in the bulk material [14]. The shape and the nature of the electrical modulus spectra reveal that the electrical relaxation processes in these polymer composites follow a stretched exponential behaviour [16]. TGA analysis enabled the studies of thermal stability of the polymer electrolyte.…”

Section: Resultsmentioning

confidence: 99%

Conductivity, dielectric behaviour and thermal stability studies of lithium ion dissociation in poly(methyl methacrylate)-based gel polymer electrolytes

Ramesh

Wong

2008

Thin films of poly(methyl methacrylate) (PMMA) with lithium triflate (LiCF 3 SO 3 ) were prepared by using the solution-casting method with PMMA as the host polymer. Ionic conductivity and dielectric measurements were carried out on these films. The highest conductivity for polymer electrolyte with a ratio of 65:35 was found to be 9.88×10 −5 S cm −1 , which is suitable for the production of mobile phone battery. Thermal gravimetric analysis was carried out to evaluate the thermal stability of the polymer electrolyte. The addition of salts will increase thermal stability of the polymer electrolyte.