Design of segmented thermoelectric generator based on cost-effective and light-weight thermoelectric alloys

•Segmented thermoelectric (TE) module operating at 500 °C for combustion engine system.•Si based light-weight TE generator increases the specific power density [W/kg].•Study of contact resistance at the bonding interfaces maximizing output power.•Accurate agreement of the theoretical predictions with experimental results.

A segmented thermoelectric (TE) generator was designed with higher temperature segments composed of n-type Mg2Si and p-type higher manganese silicide (HMS) and lower temperature segments composed of n- and p-type Bi–Te based compounds. Since magnesium and silicon based TE alloys have low densities, they produce a TE module with a high specific power density that is suitable for airborne applications. A two-pair segmented π-shaped TE generator was assembled with low contact resistance materials across bonding interfaces. The peak specific power density of this generator was measured at 42.9 W/kg under a 498 °C temperature difference, which has a good agreement with analytical predictions.