Alkali metal thermal-to-electric converter development

Initial impedance measurements of multi-BASE tube AMTEC cells have been acc omplished. These measurements were based on theoretical analyses performed by the Jet Propulsion Laboratory. These factors are derived from a plot of the apparent charge transfer resistance, R-act, as a function of the electr ical potential across the beta alumina solid electrolyte. These include the morphology factor, G, the exchange current J(0)(,)(0) and alpha, the trans fer coefficient. The factor G was given a value of 50 as a result of the in ability of present equipment to achieve 1.6 V across a single electrolyte e lement. Average values for the temperature independent charge exchange fact or, B, are also reported. These results were taken from cells with as few a s 3300 h to as many as 12,000 h of operation. The results show that if the value for G is somewhat close to actual values, then J(0)(0) and a are much lower than those reported in previous literature, resulting in an increase in the charge transfer resistance. (C) 2001 Published by Elsevier Science Ltd.