6533b833fe1ef96bd129c1ca
RESEARCH PRODUCT
Performance evaluation and stability of silicide-based thermoelectric modules
Antoine De Padoue ShyikiraPeter Hugh MiddletonGustein Skomedalsubject
010302 applied physicsMaterials scienceOpen-circuit voltage02 engineering and technologyInternal resistanceCurrent collector021001 nanoscience & nanotechnologyMagnesium silicide01 natural sciencesIsothermal processVDP::Teknologi: 500::Elektrotekniske fag: 540chemistry.chemical_compoundThermoelectric generatorchemistry0103 physical sciencesThermoelectric effectSilicideComposite material0210 nano-technologydescription
Abstract Long-term studies on thermoelectric generators based on N-type magnesium silicide (Mg2.01Si0.49Sn0.5Sb0.01) and P-type higher manganese silicide (Mn0.98Mo0.02Si1.73Ge0.02) materials are presented, in the operating temperature range of 200 °C–400 °C. Emphasis is put on the performance and reliability of the current collector configuration, especially on the hot side of the module, and on the thermomechanical stresses that are created during operation and lifetime testing as a result of large temperature gradients experienced across the thermoelectric legs. With silver (Ag) paste as contact material, the long term-stability of the uni-couples was carried out on non-metalized legs and gold metalized legs under ambient conditions. Under isothermal and thermocycling tests, the non-metalized legs showed a gradual decrease in open circuit voltage (after a period of 200 h) and increase in internal resistance. Conversely, the module made of metalized legs was robust and stable for the same isothermal period. However, after 300cycles the n-type material showed mechanical failure (cracks) but the p-type resisted. Post-operation analysis by SEM/EDS and mechanical testing revealed that oxidation, adherence of the contact material and diffusion of the bonding material were the cause of performance degradation of the unicouples.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2020-01-01 |