Liquid-solid composite electrolytes

The various fuel cell designs (Figure 1.25) can also be categorized according to their operating temperatures, electrode designs, types of electrolytes, and the type of fuel used (Table 1.26). Electrolytes can be either acidic or alkaline liquids, solids, or solid-liquid composites. The basic core of the fuel cell— called the stack—consists of the manifolds, anode, cathode, and electrolyte. 

Vega and Funk (1974) presented a thermodynamic correlation for solid-liquid equilibria in concentrated aqueous salt solutions and applied the correlation to the six-component system containing Na+, K+, Mg +, NO, SO " from 0 to 50 °C. In their correlation they define an activity coefficient as if the given salt were a non-electrolyte, although this new quantity is easily related to the mean ionic activity coefficient 7 . The derived parameters are claimed to enable correlation of equilibria for ternary and quaternary systems with errors in liquid phase composition of less than 2g salt per 100 g water. 

Fig. 39.1. (a) Schematic representation of a microsupercapacitor copper current collector (a), HUP pure ionic membrane (b), composite HUP/C electrodes (c), and plastic encapsulation (d). Diameter (D) is 10 mm and thickness (t) is 2 mm. The capacity is 1F. (b) Comparison of specific energy storage capability (capacitance x voltage per unit volume — CV/V ) vs. capacitance (C). Pp, polypropylene film capacitors Pe, polyethylene film capacitors Ta, tantalum electrolytic capacitors Al, aluminium electrolyte capacitors H2SO4/C, liquid-solid supercapacitors HUP/C, all-solid supercapacitor (with permission, American Institute of Physics). 

The Equilibrium Compositions of Electrolyte Solutions (ECES) Program is an extensive general purpose vapor-liquid-solid prediction program for aqueous electrolyte systems. The package has a number of special features, including ... 

Fujiwara N, Asaka K, Nishimura Y et al (2000) Preparation of gold — solid polymer electrolyte composites as electric stimuli-responsive materials. Chem Mater 12(6) 1750-1754 Fukushima T, Asaka K, Kosaka A et al (2005) Fully plastic actuator through layer-by-layer casting with ionic-liquid-based bucky gel. Angew Chem hit Ed 44 2410-2413 Gao R, Wang D, Heflin JR et al (2012) Imidazolium sulfonate-containing pentablock copolymer-ionic liquid membranes for electroactive actuators. J Mater Chem 22 13473-13476 Gogotsi Y, Nikitin A, Ye H et al (2003) Nanoporous carbide-derived carbon with tunable pore size. Nat Mater 2(9) 591-594... 

Moreover, the composition of a liquid may change at liquid-solid boundaries due to, for example, electrolyte concentration changes. This is expected to influence, to some extent, the value of the Hamaker constant. Thus, in the general case, the electrostatic and dispersion interactions are coupled in a complex nonlinear way, which violates the assumption of the DLVO theory. Due to the lack of appropriate theories, we should accept the hypothesis that this coupling is not too significant. 

Ionic association in liquid (polyether-Al203-LiC104) composite electrolytes. Solid State Ionics, 176(3 ), 367-376. 

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. 

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