Emf measurements were made across the lithium-rich half of the lithiumaluminum system at temperatures from 390 ~ to 550~ using a cell of the type Li/LiC1-KC1 (or LiF-LiC1-LiBr)/Li-A1. The lithium activity increases from 0.007 to approximately 0.7 over the composition range of 48-56 atomic percent (a/o) lithium (the E-phase region). A compound, Li3A12, rather than Li2A1, as reported in standard compilations, exists at temperatures up to the peritectic decomposition at 520r and forms a two-phase region of high lithium activity (>0.85) with the lithium-rich liquid phase. This compound has an estimated free energy of formation of --58 kJ/mole at 700~ The emf data indicate that the lithium-rich liquidus is about 2 a/o richer in lithium than the composition shown in standard compilations of binary phase diagrams.

Die EMK‐Messungen erfolgen an Ketten des Typs Abei Temperaturen zwischen 390 und 550°C. Die Li‐Aktivität steigt bei Änderung der Legierungszusammensetzung von 48 auf 56 Atom % (β‐Phasenbereich) stufenweise von 0,007 bis 0,7 an.