ChemInform Abstract: THE USE OF TETRAVALENT SULFUR IN MOLTEN CHLOROALUMINATE SECONDARY BATTERIES

Abstract

Es wird eine neue wiederaufladbare Zelle des Typs A in AlCl3‐NaCl‐Schmelze beschrieben, die im Temp.‐Bereich 180‐250°C arbeitet und eine Klemmenspannung von 4.2 Vbesitzt.

Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives

“…SbCl 3 [73], Cl 2 [74] and SCl 3+ [75] were first examined. In spite of their attractive energy density, these materials are not free from corrosion problems.…”

Electrochemical and Spectroscopic Studies of Sulfur in Aluminum Chloride‐N‐(n‐Butyl)Pyridinium Chloride

“…In comparison, in acidic A1CI:~-NaC1 melts, tetravalent sulfur is stable and can be used as active cathode material in long lasting secondary batteries (7)(8)(9)(10).…”

“…Electrochemical studies of several organic and inorganic species in this system and other related systems indicate that the solute chemistry and electrochemistry of these species are dependent on the melt acidity (6). Several studies have been published on the electrochemistry of sulfur in alkali metal chloroaluminate melts, partly because of potential use of positive oxidation states of sulfur as cathode-active materials in secondary molten salt batteries (7)(8)(9)(10). In basic (NaCl-rich) A1C13-NaC1 melts, sulfur can be reduced to sulfide in the form of an A1SC1-like species and oxidized to S(I) (11)(12)(13).…”

Oxidation of Sulfur in Chloroaluminate Melts of Intermediate pCl

“…However, in very acidic melts such as the 63/37 melt, some Raman spectroscopic evidence for the $2C1 + ion has been obtained (39). The interpretation of the differential pulse voltammetric results for wave C may be based on the electrode reaction S2C12 -~-8A1C14-----2SCh + + 4A12C17--}-6e [9] for which the calculated slope of the Ep vs. pC1 plot is 59.3 mV at 175~ Evidence for the SCls + ion has been obtained by Raman spectroscopy (13). The deviations of the experimental slopes (ranging from 35 to 52 mV) from the theoretical slope may be attributed to several causes, such as (i) some contribution to wave C by the chloride oxidation process at lower pC1.…”

“…The fully charged cell contains a large excess of A1CI~ (as compared to NaC1); during the discharge process the A1C1JNaC1 ratio in the cathode compartment decreases until the melt becomes saturated with NaC1 (10,11). The fully charged cell contains a large excess of A1CI~ (as compared to NaC1); during the discharge process the A1C1JNaC1 ratio in the cathode compartment decreases until the melt becomes saturated with NaC1 (10,11).…”