Gel polymer electrolytes

Figure 8.1 Beer s law-type plot of change in optical absorbance against charge density q for the cell WO3 polymer electrolyte Prussian Blue. Reprinted from Inaba, H Iwaka, M., Nakase, K., Yasukawa, H., Seo, I. and Oyama, N., Electrochromic display device of tungsten trioxide and Prussian Blue films using polymer gel electrolyte of methacrylate , Electrochim. Acta, 40, 227-232 (1995), Copyright 1995, with permission from Elsevier Science.

Wang P, Zakeeruddin SM, Moser JE, Nazeeruddin MK, Sekiguchi T, Gratzel M (2003) A stable-quasi-solid state dye-sensitized solar cell with amphiphilic ruthenium sensitizer and polymer gel electrolyte. Nature Mater 2 402-406... 

The same authors [340] have proposed another polymer gel electrolyte for Zn-Mn02 cells. 

The EDLCs, which use all-solid-state ion-conducting polymer [e.g., polyethylene oxide)/LiC104] or polymer gel electrolyte, have also been developed [3],... 

The Danish company Danionics has also developed LPB prototypes under EU contract using a lithium metal negative, a polymer gel electrolyte and a V60J3 positive. The cells had the form... 

Several polymer gel electrolytes were prepared by changing the mixing ratio of ZILs to polymer. The polymer gel electrolytes were obtained as translucent films up to 80 wt% of the ZIL/LiTFSI content. When the content of the ZIL/LiTFSI mixture was less than 40wt%, they were obtained as flexible but white films. Figure 27.4 shows the effect of ZIL/LiTFSI mixture content on the ionic conductivity for polymer gel electrolytes. The ionic conductivity of these polymer gel... 

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. 

Ohno, H., Yoshizawa, M., Ogihara, W. (2003) A new type of polymer gel electrolyte zwitterionic liquid/polar polymer mixture. Electrochim. Acta, 48, 2079-2083. 

A recent Raman and infrared vibrational spectroscopic study of ethylene carbonate containing solutions of lithium perchlorate indicated that a strong interaction is present between the Li+ ions and all the three oxygens of the plasticizer including the carbonyl group [258]. This result confirms the role of EC and PC as plasticizing solvents and has implications in understanding the conductivities of polymer gel electrolytes. 

Alkaline polymer gel electrolytes are commonly used in all- solid-state alkaline rechargeable batteries and supercapacitors. The typically used electrode materials for supercapacitors... 

Traditionally, for improving the interfacial adhesion, a surface modification is performed by a solution-based spraying or dipping method with the liquid electrolyte serving as the glue component. There exists a subsequent heating step to facilitate the formation of polymer gel electrolyte. But for some occasions, the dense polymer layer may block the penetration of the electrolyte and afterward imdermine the LIB performance. Therefore, several attempts have been conducted to alter the surface character without sacrificing the porous structure. 

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