Glass electrolyte

Rather specific structural features appear to be necessary for high ionic conductivity in crystalline solids, and as a result it may seem surprising that glasses can support high ionic conductivity. For example, a Li conductivity of 0.16mScm at 25 °C for a glass with the composition 

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These materials are introduced in Chapter 5 and only brief mention of them is necessary here. It is important to appreciate that polymer electrolytes, which consist of salts, e.g. Nal, dissolved in solid cation coordinating polymers, e.g. (CH2CH20) , conduct by quite a different mechanism from crystalline or glass electrolytes. Ion transport in polymers relies on the dynamics of the framework (i.e. the polymer chains) in contrast to hopping within a rigid framework. Intense efforts are being made to make use of these materials as electrolytes in all solid state lithium batteries for both microelectronic medical and vehicle traction applications. 

A method of characterising transport mechanisms in solid ionic conductors has been proposed which involves a comparison of a structural relaxation time, t, and a conductivity relaxation time, t . This differentiates between the amorphous glass electrolyte and the amorphous polymer electrolyte, the latter being a very poor conductor below the 7. A decoupling index has been defined where... 

On the assumption that at a glass-electrolyte interface hydroxyl ions are adsorbed, the fraction of the original charge neutralised by adsorption can be calculated from the above equations as follows. From (a) and (b)... 

Janusz, W., Dawidowicz. A.L., and Szczypa, J., Surface charge and adsoiption of sodium ions at the controlled porosity glasses/electrolyte interface, 7. Mater. Sci., 26, 4865, 1991. 

Electrolysis of Water and Nonstandard Half-Cell Potentials Before we can analyze the electrolysis products of aqueous salt solutions, we must examine the electrolysis of water itself. Extremely pure water is difficult to electrolyze because very few ions are present to conduct a current. If we add a small amount of a salt that cannot be electrolyzed in water (such as Na2S04), however, electrolysis proceeds rapidly. A glass electrolytic cell with separated gas compartments is used to keep the H2 and O2 gases from mixing (Figure 21.25). At the anode, water is oxidized as the O.N. of O changes from —2 to 0 ... 

The ion-selective properties of glass/electrolyte interfaces were recognized early in the 20th century, and glass electrodes have been used since then for measurements of pH and the activities of alkali ions (24, 37,46-55). Figure 2.4.1 depicts the construction of a typi-... 

Application of Glass Electrolytes to Solid-State Rechargeable Lithium Batteries... 

Li H., Nogami M. Ordered mesoporous phosphosilicate glass electrolyte film with low area specific resistivity. Chem. Commun. 2003 236-237... 

Yamauchi A, Sakuda A, Hayashi A, Tatsumisago M (2013) Preparation and ionic conductivities of (100 - r)(0.75Li2S 0.25P2S5) x LiBH4 glass electrolytes. J Power Sour 244 707-710... 

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