Design and Performance Study of a Thermoelectric Coupling Enhanced Heat Pipe under Extreme Lunar Conditions

Addressing the energy efficiency bottleneck of thermal management systems for lunar rovers under extreme lunar conditions, this study proposes a novel ammonia-based heat pipe network design. By achieving directional heat transport from isotopic heat sources to all-solid-state batteries, it elevates battery operating temperatures and reduces self-heating energy consumption, thereby realizing thermoelectric coupling enhancement. The heat pipe employs a triple composite structure, including a dual-layer shell (inner layer: 6061-T6 aluminum alloy; outer layer: lunar regolith-based protective coating), a trapezoidal micro-groove wick structure (capillary driving force: 1.8 kPa), and a nano-modified ammonia working fluid (heat transfer efficiency $\gt90 \%$ across a wide temperature range). Through mathematical modeling and experimental validation, the novel heat pipe achieves a heat transfer power of 152 W at lunar night temperatures ($170^{\circ} \mathrm{C}$), a $114 \%$ improvement over traditional heat pipes, with battery temperature fluctuations controlled within $\pm 25^{\circ} \mathrm{C}$. Rover endurance increased from 320 km to 620 km (a $93.8 \%$ improvement). Additionally, the heat pipe’s thermal resistance increases by only $3 \%$ under a $300^{\circ} \mathrm{C}$ temperature difference, with a lifespan of 10 years, demonstrating excellent long-term stability. These results indicate that the novel heat pipe significantly enhances energy utilization and endurance for lunar rovers, providing efficient thermal management support for lunar base resource transport, with broad potential for deep space exploration and terrestrial extreme environments.