3D-Printed Geometrical-Optimized Bridge-Type Thermoelectric Generators with a High Output Power and Mechanical...

Area of Science:

• Materials Science and Engineering
• Energy Conversion and Storage
• Additive Manufacturing

Background:

• Geometric design significantly impacts thermoelectric (TE) device performance, affecting energy conversion efficiency and mechanical integrity.
• Traditional TE device structures can suffer from stress concentration due to mismatched thermal expansion coefficients.

Purpose of the Study:

• To develop a novel bridge-type thermoelectric device using 3D printing for enhanced performance and mechanical robustness.
• To investigate the electrical and mechanical properties of the 3D-printed bridge-type TE device compared to traditional designs.

Main Methods:

• Fabrication of p-type Bi_0.5Sb_1.5Te₃ (BST) and n-type Bi₂Te_2.7Se_0.3 (BTS) thermoelectric materials via Selective Laser Melting (SLM).
• Utilized 3D printing's shape-customization capabilities to create a novel bridge-type TE device structure.
• Conducted comparative electrical and mechanical property analyses between bridge-type and traditional π-type TE devices.

Main Results:

• Achieved ZT values of 1.12 for p-type BST and 1.02 for n-type BTS.
• The bridge-type design demonstrated an 18% improvement in theoretical output power (0.168 W) and an 11% increase in conversion efficiency (5.4%).
• Reduced maximum thermal stress in the bridge-type module to 89.9 MPa (82.5% of traditional structures), mitigating stress concentration.

Conclusions:

• 3D printing facilitates the creation of advanced geometric designs for high-performance thermoelectric devices.
• The bridge-type structure offers superior electrical performance and enhanced mechanical durability for energy-harvesting applications.
• Geometric optimization via 3D printing is crucial for developing robust and efficient thermoelectric systems.