Breakthrough in solid-state energy harvesting: segmented thermoelectric module achieves 12.7% efficiency

A research team led by Ge Fu, Shangchao Lin, Yang Liu, Yiling Duan, Yixuan Liu, and Qilin Zhang from Shanghai Jiao Tong University, Shanghai Institute of Space Power Sources, and The University of Tokyo has developed a highly efficient segmented thermoelectric (TE) module capable of converting waste heat directly into electricity with remarkable effectiveness. This advancement, detailed in a new study published in ENGINEERING Energy, successfully achieves an outstanding peak energy conversion efficiency of 12.7%.

Solid-state thermoelectric power generation is gaining worldwide attention for its vast potential in recovering industrial waste heat and powering deep-space devices. However, traditional TE modules are often limited because a single material cannot maintain optimal performance across large temperature gradients. To overcome this challenge, a collaborative research team engineered a segmented TE module that strategically combines different high-performance materials.

Key Research Outcomes and Highlights:

• Innovative Material Segmentation: The researchers constructed p-type TE legs using a combination of GeTe (optimized for mid-to-high temperatures) and BST (Bi₂₋ₓSbₓTe₃, optimized for low temperatures), alongside structurally optimized n-type SKD (skutterudite, Yb₀.₃Co₄Sb₁₂) legs.
• Comprehensive Structural Optimization: By utilizing multiphysics-field finite element method (FEM) simulations, the team identified the ideal module configurations. They determined the optimal values for three critical shape factors: the segmentation ratio (0.35), the height-to-area ratio (0.67 mm⁻¹), and the cross-sectional area ratio between the p- and n-type legs (1.85).
• Enhanced Stability and Minimized Resistance: A thin nickel (Ni) foil was integrated at the GeTe/BST interface. This Ni foil acts as both a metallization layer and a critical diffusion barrier, effectively minimizing internal contact resistances and ensuring high-temperature stability without elemental interdiffusion.
• Record-Breaking Conversion Efficiency: Operating under a temperature difference (ΔT) of 500 K, the optimized segmented module achieved an outstanding peak energy conversion efficiency of 12.7%.
• Substantial Power Density Output: The module delivered a maximum power output of ~0.43 W at ΔT = 500 K, corresponding to a module-level power density of 0.35 W/cm² per module area and 143 W/kg per module weight. When considering the effective active area of the TE material, the effective power density reached an impressive 1.51 W/cm².
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Overall, the maximum power density and energy conversion efficiency of this optimized segmented module increased by 35% and 21%, respectively, compared to an unsegmented baseline module. These findings decisively demonstrate the effectiveness of the optimized broad-temperature leg-segmentation strategy for next-generation, high-performance solid-state energy harvesting technologies.

Journal: ENGINEERING Energy 

Read the full article for free: https://rdcu.be/fsX3c

Cite this article: Fu, G., Lin, S., Liu, Y. et al. Achieving 12.7% energy conversion efficiency in segmented GeTe/BST-SKD thermoelectric modules via broad-temperature and structural optimizations. ENG. Energy 20, 10811 (2026). https://doi.org/10.1007/s11708-026-1081-1