Solid polymeric electrolytes based

Solid polymeric electrolytes based on HEC plasticized with different quantities of glycerol and containing LiCFsSOs salt were reported by Machado et al. The samples were prepared in the transparent film form, where the transparency depended on the plasticizer quantity, with very good adhesion properties and best ionic conductivity values of 1.07 x 10" S/cm at 30 °C and 1.06 X 10 S/cm at 83 C for the samples plasticized with 48 wt% of glycerol and containing [0]/[Li] = 6 of LiCFsSOs. It was demonstrated that... 

Solid Polymeric Electrolytes Based on Crosslinked MEEP-Type Materials... 

J.M. Sansinena, V. Olazabal, T.F. Otero, C.N. Polo da Fonseca, and M.-A.D. Paoli, A solid state artificial muscle based on pol3fpyrrole and a solid polymeric electrolyte working in air, Chem. Comm., (22), 2217-2218 (1997). 

Lithium-metal-polymer (LMP) is a relatively new technology being promoted by the Canadian Avestor Limited Partnership based in Boucherville, Quebec, for telecommunications applications. Avestor s LMP cell is built up from four elements. An ultra-thin metallic lithium foil anode combines the roles of lithium source and current collector. The solid polymeric electrolyte is made by dissolving a lithium salt in an appropriate co-polymer. The metallic oxide cathode is based on a reversible intercalation compound of vanadium oxide, blended with a lithium salt and a polymer to produce a plastic composite. Finally, an aluminium foil forms the current collector. Avestor cells can operate within the temperature range -40 °C to +65 °C. 

Abstract In this chapter a brief review on solid polymeric electrolytes is given, followed by the discussion of challenges and requirements to fulfil in order to commerciahse them. Among various ways of polymeric electrolyte modification, composites with ceramic phases are discussed in detail here. Special attention is paid to electrolytes for lithium cells, based on polyethers. The main achievements, theories developed and precautions for future researchers willing to work in this area are discussed. 

MuszYNSKA, M., WYCisLiK, H. and SIEKIERSKI, M., 2002. Composite polymeric electrolytes based on poly(ethylene oxide) matrix and metallic aluminum filler. Solid State Ionics, 147(3 ), 281-287. 

SILVA, G.G., LEMES, N.H.T., DA FONSECA, c.N.P. and DE PAOLi, M., 1996. SoUd State polymeric electrolytes based on poly(epichlorohydrin). Solid State Ionics, 93(1-2), 105-116. 

A different grafting reaction was performed by Machado et aL using the principle of Schiff base, i.e. a reaction between primary amine and ketone groups through imine bonds, as shown in Hg. 3.3. This reaction can possibly also result in a wide variety of networks, which can be used as solid polymeric electrolytes when associated with an appropriate salt. To achieve this route it was necessary to convert HPC secondary hydroxyl into ketone groups under mild experimental conditions using 1-chlorobenzotriazol. The networks were obtained by grafting with Jeffamines (diamines with polyether chains) as shown in Fig. 3.3. 

DRAGUNSKI, D., PAWLICKA, A., Starch based solid polymeric electrolytes. Mol. Cryst. Liq. Cryst., 2002,374, 561. 

Polyethylene oxide) associates in solution with certain electrolytes (48—52). For example, high molecular weight species of poly(ethylene oxide) readily dissolve in methanol that contains 0.5 wt % KI, although the resin does not remain in methanol solution at room temperature. This salting-in effect has been attributed to ion binding, which prevents coagulation in the nonsolvent. Complexes with electrolytes, in particular lithium salts, have received widespread attention on account of the potential for using these materials in a polymeric battery. The performance of solid electrolytes based on poly(ethylene oxide) in terms of ion transport and conductivity has been discussed (53—58). The use of complexes of poly(ethylene oxide) in analytical chemistry has also been reviewed (59). 

In the event of abuse cases, such as short circuit, exposure to air, or overcharge or overdischarge, it is assumed that solid state Li batteries based on polymeric electrolyte systems should be much less dangerous than liquid-based batteries. It is expected that the former battery systems would be much better protected in the above cases from thermal runaway than are the liquid-based batteries. 

Ion conducting polymers may be preferable in these devices electrolytes because of their flexibility, moldability, easy fabrication and chemical stability (for the same reasons that they have been applied to lithium secondary batteries [19,48,49]). The gel electrolyte systems, which consist of a polymeric matrix, organic solvent (plasticizer) and supporting electrolyte, show high ionic conductivity about 10 5 S cnr1 at ambient temperature and have sufficient mechanical strength [5,7,50,51], Therefore, the gel electrolyte systems are superior to solid polymer electrolytes and organic solvent-based electrolytes as batteries and capacitor materials for ambient temperature operation. 

In EMST, electrochemical reactions based on Faradaic reactions such as metal deposition, anodic dissolution, various oxide formation, and anodic polymerization are common. Ion transfer reactions (ITR) from the electrolyte to the solid or solid to electrolyte can be used for formation of positive or negative structure by deposition or dissolution. ITR can also be performed by electron transfer reaction (ETR) in chemical reactions in the bulk electrolyte. Pure ETR cannot be utilized for microstructuring. Local field distributions at the interface and inside the microstmcrnre play an important role during vertical structure formation by depositions or removal. It also depends on the ionic conductivity of the materials to be deposited or dissolved such as metal, semiconductor, and oxides. 

Hashmi and Upadhyaya compared the electrochemical properties of the electrochemically synthesized MnO /PPy composite electrodes, fabricated with different electrolytes, namely polymer electrolyte film (polyvinyl alcohol [PVA]-HjPO aqueous blend), aprotic liquid electrolyte (LiClO -propylene carbonate [PC]), and polymeric gel electrolyte (poly methyl methacrylate [PMMA]-ethylene carbonate [EC]-PC-NaClO ) [60]. The cell with aqueous PVA-H PO showed non-capacitive behavior owing to some reversible chemical reaction of MnO with water, while the MnO / PPy composite was found to be a suitable electrode material for redox supercapacitors with aprotic (non-aqueous) electrolytes. The solid-state supercapacitor based on the MnO /PPy composite electrodes with gel... 

Hashmi SA, Suematsu S, Naoi K (2004) All solid-state redox snpracapacitors based on supramolecular 1,5-diaminoanthraquinone oligomeric electrode and polymeric electrolytes. J Power Sources 137 145-151... 

We do not discuss however the important field of polymer ionics and polymer electrolytes. This class of materials consists of polar macro-molecular solids in which one or more of a wide range of salts has been dissolved. A classic example that has been studied a great deal is the combination of poly(ethylene oxide) (PEO) containing LiX salt as solute. The reader is referred to a recent monograph edited by Scrosati and to review articles by Vincent, Linford, Owen and to a volume edited by MacCallum and Vincent for further information on this rapidly expanding area of polymer science. The major focus in this chapter (and indeed in this book) is on electroactive polymers used as electrode materials. Polymeric electrolytes, although important in both a technological and fundamental sense, present different problems to those discussed in this volume, and so we restrict discussion to electroactive polymer-based chemically modified electrodes. 

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