Structure of Current Collector and Flow Characteristics of Sodium Vapor for the Alkali Metal Thermoelectric Converter

The present paper discusses current collecting structures on electrodes for the alkali metal thermoelectric converter (AMTEC). For practical large area electrodes, a new current collector which has low electrical resistance and less handling must be introduced instead of the conventional type collector with metal screens tied by wires. Two concepts have been examined in this paper. The first is a ring type current collector deposited by the plasma spray method. This kind of current collector has the advantage of a significant reduction of contact resistance between electrodes and current leads. The detailed analysis on potential drop along the electrodes has been performed and the influence of the collector distance has been examined. The second is use of metal sponge for the current collector. This collector is intended for easy attachment. Sodium vapor flow resistance and its influence have been considered.