Sodium beta

Beta-alumina, mentioned in Section 1.2.2.2, is just the best known and most exploited of this family. They have been developed by intensive research over more than three decades since Yao and Kummer (1967) first reported the remarkably high ionic conductivity of sodium beta-alumina. Many other elements have been used in place of sodium, as well as different crystallographic variants, and various processing procedures developed, until this material is now poised at last to enter battery service in earnest (Sudworth et al. 2000). 

Fig. 7.17 Relation of the spinel structure (left) io the structure of sodium beta alumina (right). The sodium ions are free to move in the open spaces between spinel blocks, held apart by Al—O—Al pillars in the "parking garage structure. [In part from Wells. A. F. Structural Inorganic Chemistry, 5th ed. Oxford University Oxford, 1984. Reproduced with permission. ...

Another example of this type of intercalation compound is sodium beta alumina where the sodium ions are free to move between the spinel layers. The sodium ions can be replaced by almost any +1 cation such as Li. K, Rb+, Cs. NHJ, H 0 Tl+, Ga+, NO+, etc. The conductivity of these materials varies with the size of the ions moving between the fixed-distance (A)—0—Ai) layers. 

Another solid electrolyte that may lead to important practical applications is sodium beta alumina. Its unusual name comes from a misidertificalion and an uncer-... 

Fig. 7.18 Sodium/sulfur battery with a sodium beta alumina solid electrolyte.

Consider the battery in Fig. 7.18. The sodium beta alumina barrier allows sodium ions formed at the anode to Row across to the sulfur compartment, where, together with the reduction products of the sulfur, U forms a solution of sodium trisulfide in the sulfur. The latter is held at 300 CC to keep it molten. The sodium beta alumina also acts like an electronic insulator to prevent short circuits, and it is inert toward both sodium and sulfur. The reaction is reversible. At the present state of development, when compared with lead storage cells, batteries of this sort develop twice the power on a volume basis or four times the power on a weight basis. 

For use in these equations, n2s is obtained from Equation 6. The volume of a sodium beta-naphthalenesulfonate molecule, calculated from bond lengths and appropriate van der Waals radii, is taken to be 330 A.3. An average molecular volume of water of 30 A.3 was calculated from the density of water at 25.0°C. Most of the numerical work was done on a Honeywell 800 digital computer. The symmetric surface excess and the surface charge densities were calculated over a wide range of surface potentials and concentrations. 

Figure 7. Experimental adsorption isotherm of sodium beta-naphthalenesulfonate on graphitized Sterling FT, A, and the corresponding calculated potential isotherm, B...

Refs. [i] Julien C (1997) Solid state batteries. In Gettings PJ, Bouwmeester HJM (eds) The CRC handbook of solid state electrochemistry. CRC Press, Boca Raton, pp 374-410 [ii] Braithwaite [W, Auxer WL (2002) Sodium-beta batteries. In Linden D, Reddy TB (eds) Handbook of batteries, 3rd edn. McGraw-Hill, New York, pp 40.00-40.31... 

The susceptor materials used in high-temperature processing include zirconia, boron nitride, graphite, carbon black, sodium-beta alumina, zinc oxide, and silicon carbide. While each of these susceptor materials has relatively high dielectric losses at room temperature, silicon carbide is also refractory with a relatively good resistance to oxidation at temperatures up to roughly 1500°C.t ° ... 

Schwartz, M. K., Kessler, G., and Bodansky, O., Comparison of serum alkaline phosphatase activities determined with sodium beta glycerophosphate and sodium phenylphosphate as substrates. Am. J. Clin. Pathol. 275-280 (1960). 

Brisley, R.J. and Fray, D.J. (1983) Determination of the sodium activity in aluminum and aluminum silicon alloys using sodium beta alumina. Metall. Trans. 

The U.S. DOE, as a major participant in the USABC and PNGV programs, has been working to address infinstructure barriers to the commercial acceptance of EVs since the early 1990s. As an outgrowth of a workshop held in 1991 on sodium-beta batteries... 

P. Patil, G.L. Henriksen, D.R. Vissers, and C. Christianson, "Shipping, Use and Disposal/Recycle Considerations for the Sodium/Beta Batteries in EV Applications," presented at the DOE/EPRI Beta (Sodium/Sulfiir) Battery Workshop VIII, Chester, England, June 1990. 

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