Properties of fused polysulphides—III. EMF measurements on the sodium-sulphur cell, and sulphur activities and constitution in fused sodium polysulphides

✍ Scribed by B. Cleaver; A.J. Davies

• Publisher: Elsevier Science
• Year: 1973
• Tongue: English
• Weight: 624 KB
• Volume: 18
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(73)80064-7

✦ Synopsis

Expressions are derived for the emf of the sodium-sulphur cell in the fully charged state (Et) and in a partly discharged state (El). It is shown that (& -El) is related to the variation of sulphur activity with the composition of the sodium polysulphide melt produced in the cell reaction, and that the sulphur activity can be calculated if E, is known over a range of compositions. The sulphur activity in sodium polysulphide melts was also measured by a transpiration method. The two sets of results are in good agreement.

The e&of a sodium polysulphide concentration cell with transference (Es) was also measured. The results show that all the sulphur in the melt is contained in polysulphide anions; no free sulphur is present.