Single ionic polymer electrolyte preparation

Abstract The chapter begins by discussing the characters and composition of polymer electrolytes for electrochromic devices. It then describes the four types of the polymer electrolytes dry solid polymer electrolyte, gel polymer electrolyte, porous gel polymer electrolyte and composite solid polymer electrolyte, their preparation procedures and properties especially ion conductivity of the samples. Finally, new types of polymer electrolytes including proton-conducting, alkaline, single ionic polymer electrolytes and electrolytes with ionic liquids are also introduced. 

Single lithium ion conducting polymer electrolytes have been prepared by the copolymerizahon of hthium(4-styrenesulfonyl)(trifluoromethanesulfonyl) imide and methoxy-poly(ethylene glycol) acrylate [117]. The highest ionic conduchvihes for the copolymer electrolytes are 7.6 x 10 S cm at 25 °C and then grow to reach 10 " S cm at 60 °C, at a raho of ethylene oxide to Li+ of 20.5. 

The aforementioned polymeric electrolytes have been effectively used in polymer electrolyte fuel cells operating up to In order to study the single cell performance and apart from the high ionic conductivity of the membrane, several parameters residing the MEA constmction must be taken into account in order to have optimum performance of the cell. Some of these parameters are the amount of the catalyst the ionomer-binder used at the electrodes and its percentage, electrode surface and the preparation method, pressure and the temperature of the MEA assembling and design and constmction parameters of the cell. ... 

Blending a polymer electrolyte with a polymer matrix that is beneficial to ionic conduction. For example, a single ion conductor mixture is prepared by blending a high molecular weight PEO with a polymer electrol5de, poly(lithium 2-(4-carboxyl hexafluorobutyl acyloxy) ethyl methacrylate). However, the ionic conductivity is low, 4 x 10 S/cm at 30°C. 

A single-ion conductor containing a PEO unit can also be prepared for gel polymer electrolytes. For example, the lithium salt prepared as shown in Figure 11.3 is plasticized with EC or PC solvent, though the LP-ion transference number decreases with the amount of solvent added. When the number of EO units is greater than three, it behaves as a single-ion conductor and follows the VTF equation. The ionic conductivity remains relatively constant with varying numbers of EO units. 

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