The rest potential-concn. curve was first applied to measure the concentration of an alloy. Attempt to use the V-c curve of Al-Li alloy in measuring the diffusion coefficient of Li atom in liquid Al with anode chronopotentiometry at 720? was made and DLi/Al = 4.94 ?10-5 cm2.s-1 was obtained. The value is well consistent with the theor. value, DLi/Al = 4.85 ?10-5 cm2.s-1 in terms of Stokes-Einstein equation.

Key words: CONCENTRATION, DIFFUSION COEFFICIENTS, ELECTRIC POTENTIAL, ALUMINIUM ALLOYS, CURVED LINE DIAGRAM, LIQUID METAL HEAT CONVECTION, ELECTROCHEMICAL METHOD, LITHIUM ALLOYS