Highly conductive polymer electrolyte

Noda and Watanabe [42] reported a simple synthetic procedure for the free radical polymerization of vinyl monomers to give conducting polymer electrolyte films. Direct polymerization in the ionic liquid gives transparent, mechanically strong and highly conductive polymer electrolyte films. This was the first time that ambient-temperature ionic liquids had been used as a medium for free radical polymerization of vinyl monomers. The ionic liquids [EMIM][BF4] and [BP][Bp4] (BP is N-butylpyridinium) were used with equimolar amounts of suitable monomers, and polymerization was initiated by prolonged heating (12 hours at 80 °C) with benzoyl... 

Many approaches have been developed for the production of ionic liquid-polymer composite membranes. For example, Doyle et al. [165] prepared RTILs/PFSA composite membranes by swelling the Nafion with ionic liquids. When 1-butyl, 3-methyl imidazolium trifluoromethane sulfonate was used as the ionic liquid, the ionic conductivity ofthe composite membrane exceeded 0.1 S cm at 180 °C. A comparison between the ionic liquid-swollen membrane and the liquid itself indicated substantial proton mobility in these composites. Fuller et al. [166] prepared ionic liquid-polymer gel electrolytes by blending hydrophilic RTILs into a poly(vinylidene fiuoridej-hexafluoropropylene copolymer [PVdF(HFP)] matrix. The gel electrolytes prepared with an ionic liquid PVdF(HFP) mass ratio of 2 1 exhibited ionic conductivities >10 Scm at room temperature, and >10 Scm at 100 °C. When Noda and Watanabe [167] investigated the in situ polymerization of vinyl monomers in the RTILs, they produced suitable vinyl monomers that provided transparent, mechanically strong and highly conductive polymer electrolyte films. As an example, a 2-hydroxyethyl methacrylate network polymer in which BPBF4 was dissolved exhibited an ionic conductivity of 10 S cm at 30 °C. 

Noda A. Watanabe, M., Highly conductive polymer electrolytes prepared by in situ polymerization of vinyl monomers in room temperature molten salts, Electrochim. Acta 2000, 45, 1265-1270. 

High conductivity but a complete lack of dimensional stability is not a recipe for success. The viscosity of some completely amorphous, high conductivity polymer electrolyte materials including MEEP and certain early, over-plasticized PEO-based systems, is too low for the electrolyte to remain in position. 

For the purpose of the discussion here, highly conductive polymer electrolytes are defined as those which have conductivities of greater than or equal to 10" Scm at room temperature. They may be broadly classified as (i) conventional polymer electrolytes and (ii) non-conventional polymer electrolytes. It is to be noted that while I will draw ample examples from the literature to illustrate the topics of discussion, no attempt will be made to present a comprehensive list of highly conductive polymer electrolytes developed to date. 

Many other types of improved, highly conductive polymer electrolytes are presently under development in various laboratories (see Chapter 3). Various choices are now available for realizing advanced laminated configurations and the most promising among them will be discussed in the next session. 

Indeed, the use of proper highly conducting polymer electrolytes, in addition to the fast response and to the reliability associated with the... 

M. D. Guiver, A new class of highly-conducting polymer electrolyte membranes aromatic ABA triblock copolymers. Energy Environ. Sci. 5 (1) (2012) 5346-5355. 

Abraham, K. M., Highly conductive polymer electrolytes, in Applications of Electroactive Polymers (B. Scorsati, ed.), Chapman Hall, New York, 19993, pp. 75-112. 

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