Radical-Ion Melts of Aluminium, Gallium and Sulfur Halides for Novel Power Sources

Abstract

In the phase diagrams of the binary systems: aluminium chloride (bromide) — sulfur chloride (bromide) and gallium chloride (bromide) — sulfur chloride (bromide), incongruently melting 2:1, 1:1 and 1:2 compounds have been revealed. The liquid state region is -20 to +200 °C; electrical conductivity of the melt is 0.1-0.01 Ω-1 cm-1. Paramagnetic species with g 1 = 2.014 and g 2 = 2.038 have been detected, the latter being assigned as a sulfur-containing radical. The extreme values in the composition- property (electrical conductivity, viscosity, molar volume, EPR signal intensity) diagrams are in the region of the 2:1 and 1:1 compounds and indicate their existence in the liquid phase. The fact that charge and free electron belong to the same species follows from the simultaneous decrease in EMF and EPR signal intensity in a discharge cell based on the aluminium systems, and corroborates the radical-ion nature of the melts. The aluminium(III) chloride system was used as cathodic material for cells of two types.