Electrolyte crystalline

Crystalline solid electrolytes which conduct Ag, Cu , TH, Li , Na , K , and F as well as many divalent and trivalent cations are 

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Diffusion and migration in solid crystalline electrolytes depend on the presence of defects in the crystal lattice (Fig. 2.16). Frenkel defects originate from some ions leaving the regular lattice positions and coming to interstitial positions. In this way empty sites (holes or vacancies) are formed, somewhat analogous to the holes appearing in the band theory of electronic conductors (see Section 2.4.1). 

In crystalline electrolytes, conduction pathways for the mobile ions... 

Ion solvation is of vital importance in the dissolution of an electrolyte [2-7]. Figure 2.1 shows the Bom-Haber cycle for the dissolution of a crystalline electrolyte,... 

Fig. 2.1 D issolution process of crystalline electrolyte MX into a solvent (see text).

AH , AS at, AG°at Lattice enthalpy, entropy, and Gibbs energy of the crystalline electrolyte AH v, AS V, AG°V Enthalpy, entropy, and Gibbs energy of solvation of the electrolyte AG° Gibbs energy of solution of the crystalline electrolyte. Taken from Table 1 in Ref. [3], Chapter 1. 

As described in Section 2.1, the solubility of a crystalline electrolyte is detennined by the difference between the lattice Gibbs energy and the solvation energy of the electrolyte. For a given electrolyte, the solubility increases with the increase in the... 

The equilibrium between a crystalline electrolyte and its ions in a solvent can be expressed by the equation... 

It seems clear that, when the source of protons is made of water, contained either in a dielectric layer or in a crystalline electrolyte, hydrolysis is necessary to lead to proton formation and it is then difficult to avoid gas evolution at the interfaces of the cell. When protons are provided through acid functions, WO3 is no longer stable if the electrolyte contains free water. Then, the use of acid anhydrous electrolytes seems to be very attractive. We report in Table 38.3 some results obtained in ECDs, but very little information is yet available on the characteristics of these cells. The structure of the cell is the following... 

When Armand [16, 17] presented the results of his original studies on PEO-based polymer electrolytes, he was influenced by knowledge of the conduction processes in conventional, crystalline electrolytes and therefore envisaged transport within the ionically conducting polymer as taking place in the crystalline regions. This seemed implausible to polymer chemists and Berthier [19] was soon able to show by solid state NMR studies that ionic transport in fact occurred within the amorphous regions. 

Figure 7.4 shows an initial nonuniform distribution of element i in a medium of j. Atoms of species i diffuse from the region of high concentration to the region of low concentration and establish a more imiform concentration distribution of the species. Self-diffusion also takes place in a relatively pure crystalline solid material controlled by a process known as vacancy mechanism or the hopping process. The ion transport in crystalline electrolyte is controlled by this vacancy diffusion or hopping diffusion mechanism. In this... 

Equation 7.45 is similar to Equation 7.40 and gives a direct relation between the charge conductivity and the ion concentration. In a crystalline electrolyte, the ion concentrations and the number of vacancy sites are controlled by doping the base material with an impurity element. 

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