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arXiv · 2005.01585

Hierarchical macro-nanoporous metals for leakage-free high-thermal conductivity shape-stabilized phase change materials

Yaroslav Grosu·Yanqi Zhao·Alberto Giacomello·Simone Meloni·Jean-Luc Dauvergne·Artem Nikulin·Elena Palomo·Yulong Ding·Abdessamad Faik
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Abstract

Impregnation of Phase Change Materials (PCMs) into a porous medium is a promising way to stabilize their shape and improve thermal conductivity which are essential for thermal energy storage and thermal management of small-size applications, such as electronic devices or batteries. However, in these composites a general understanding of how leakage is related to the characteristics of the porous material is still lacking. As a result, the energy density and the antileakage capability are often antagonistically coupled. In this work we overcome the current limitations, showing that a high energy density can be reached together with superior anti-leakage performance by using hierarchical macro-nanoporous metals for PCMs impregnation. By analyzing capillary phenomena and synthesizing a new type of material, it was demonstrated that a hierarchical trimodal macro-nanoporous metal (copper) provides superior antileakage capability (due to strong capillary forces of nanopores), high energy density (90vol% of PCM load due to macropores) and improves the charging/discharging kinetics, due to a three-fold enhancement of thermal conductivity. It was further demonstrated by CFD simulations that such a composite can be used for thermal management of a battery pack and unlike pure PCM it is capable of maintaining the maximum temperature below the safety limit. The present results pave the way for the application of hierarchical macro-nanoporous metals for high-energy density, leakage-free, and shape-stabilized PCMs with enhanced thermal conductivity. These innovative composites can significantly facilitate the thermal management of compact systems such as electronic devices or high-power batteries by improving their efficiency, durability and sustainability

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BibTeXRIS

Yaroslav Grosu, Yanqi Zhao, Alberto Giacomello, Simone Meloni, Jean-Luc Dauvergne, Artem Nikulin, Elena Palomo, Yulong Ding, Abdessamad Faik. 2020-04-30. Hierarchical macro-nanoporous metals for leakage-free high-thermal conductivity shape-stabilized phase change materials. https://doi.org/10.1016/j.apenergy.2020.115088

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