Thermoelectric converter with projecting cell stack

A thermoelectric converter comprising:

• a plenum;
• a partition secured to the plenum in an orientation that divides the plenum into first and second chambers;
• a plurality of alkali-metal thermoelectric conversion cells disposed in a stack and electrically coupled in series to generate a voltage in proportion to the number of thermoelectric conversion cells in the stack, the thermoelectric conversion cells including an initial conversion cell and a final conversion cell wherein (i) the initial conversion cell is closest to the partition and the stack extends into the first chamber in a direction towards the final conversion cell and (ii) the initial conversion cell is secured to the partition over an opening therein, a final conversion cell is unsecured with respect to the partition and the plenum;
• and
• a lid secured to the final conversion cell of the stack to separate an interior region of the stack from the first chamber, the interior region of the stack forming part of the second chamber by virtue of the opening in the partition.